600HP that gets 16MPG with a Holley Tunnel Ram and 2 Holley 660 Carbs

[@bobwhite5440]

phenomenal video. you are sharing carb tuning secrets that very few or zero carb tuners will. you're also doing it with language that everyone can understand. great job. keep up the outstanding work. more, more, more ...

[@UnityMotorSportsGarage]

Thank you for the kind words... I want people to learn all that they can... Even from my mistakes along the way! Because people are so quick to dismiss the carb and say FI is sooo much better and while I'm a fan of FI.. I know what can be done with a properly tuned carb..

[@mustangandfrankenstein]

@@UnityMotorSportsGarage ahem to passing on the knowledge .i agree with ya 100 percent .can I drop my blown up notch back off to ya and have ya do that to it.its got the same setup kinda .460 dual holley 600s.let me know brother and keep the videos coming.love em.besafe.

[@19jody72]

Man..I'm really liking this channel!

[@UnityMotorSportsGarage]

Jody, Thank you Sir!!

[@StupidFastTruck]

Great video! Carbs are a lost art these days. Using a wideband to dial it in was really smart, your knowledge of the various circuits in a Holley is impressive.

[@UnityMotorSportsGarage]

Thanks for the kind words!! I have always loved working on Holley Carbs and they can be WAY more adjustable than people believe... I Love the new Fuel Injection systems that are out now... but the Holley Carb is far from Dead!!!

[@cuzz63]

@@UnityMotorSportsGarage seems like they arent all the adjustable if they need to be drilled and tapped. Seems like a good carb engineer would have designed it so you could make minor adjustments easily...change jets to get in ballpark then a screw on the outside to adjust for fine tuning.

[@UnityMotorSportsGarage]

Most of the Carbs The XP/HP Holley's and Just about all Quickfuel carbs and many others you can buy today have these features.... But 99% of people don't bother messing with these circuits because they don't really understand what they do! Andy

[@cuzz63]

@@UnityMotorSportsGarage cool, I wasnt aware of that, my Holley is older and doesnt have that but it runs decent but sucks gas. Your right its a lost art, I know back years ago I hated Holleys but nobody I knew was this knowledgeable about them and we didnt have KZbin or the knowledge to do the research, couldnt get books on Holleys at the library.

[@rickyhunter3514]

Here from uncle tony. Digging the channel bro.

[@UnityMotorSportsGarage]

Thanks for coming over and Subscribing!!! Please help us spread the word about the channel. Andy

[@deanstevenson6527]

All the things David Vizard taught from 1977 to 1988 you are doing. What a great disciple to the craft of making carbs work Andy. Thanks for sharing!

[@UnityMotorSportsGarage]

Thanks for the kind words!!! He is my mentor... Great guy Thanks for Subscribing to the channel! I hope you enjoy the content Andy

[@deanstevenson6527]

Unity MotorSports Garage : Love it All Sir.

[@richardreaves5007]

Great job Andy. You really opened up my eyes on Holly carbs, never knew there was so much adjustability in them for street performance. Got to say really learning a lot through your channel. Keep up the Great work!🏁

[@UnityMotorSportsGarage]

Thanks Brother! It is amazing to me that the engineers back in the 50's covered all of these bases who designed the Holley 4150/4160 series.. because it has changed very little through the years! Andy

[@flinch622]

The mod [12:00] to get tunability on the transfer slot is gold. Dual quads kind of bends original design into areas that need a little help. I assume it was sized down?

[@UnityMotorSportsGarage]

When you run a setup like this trimming fuel from the idle and transfer slots is key to making it happy! Thanks for watching Andy

[@kevinjennische8209]

Gr8! videos, if you put a little chapstick on those carburetor gaskets they won't stick.

[@UnityMotorSportsGarage]

That is a good trick, I have also used WD40 with good success.. Thanks for Watching!!! Please Subscribe and help me spread the word about the channel! Andy

[@rokkebill]

You sir are the MAN ! Thank You so much for this video. Everyone talks about jetting bla bla bla, when as you said, the fuel economy is in the transition circuit + manifold adjustable vacuum. I`ve tested this in my 502. Put in 99 jets front and rear. A/f ratio stays the same as before up until 2450rpm cruising, then the main circuit kicks in with barely leaning a mm on the throttle. This video was a great way to show us how it`s done for real. Can`t like this video enough. Thank You again Sir !

[@UnityMotorSportsGarage]

Thanks for watching! and you are correct... Its about making all of the circuits in the carb work together! Please Subscribe and help me spread the word about the channel!

[@johnwilburn]

Amazing..... I've worked with Holleys for years and learned a bunch of stuff!

[@UnityMotorSportsGarage]

Thanks Brother... I learned a ton from David Vizard... He took me under his wing over 15 years ago... I owe all of my Holley tuning ability to him! People don't give Carbs enough credit... If you have a Wideband 02 you can dial it in just as good as ANY fuel injection... You just have to invest the time... People now days want everything here and now... So when are we going to get some of those Transmission vids??? Andy

[@johnwilburn]

@@UnityMotorSportsGarage It'll be a little while on the trans just because I’m doing a project and just posting what I do as I do it. The engine and transmission will probably be a winter time thing. I love carburetors!

[@virtuestreams2616]

Researching questions, exploring plausible solutions, and testing outcomes are qualities of independent thinkers: well done! Sharing knowledge, on the other hand, reveals one’s passion, generosity, and altruistic nature-thank you and congratulations as you are a teacher. Peace-out!

[@UnityMotorSportsGarage]

Hey that is what it is all about!!! Sharing knowledge! Thanks for coming over.. please Subscribe and help us spread the word about the channel!!! Andy

[@victorriceroni8455]

Excellent. Using modern tech that incorporates the supercomputer between your ears instead of taking it out of the loop.👍

[@UnityMotorSportsGarage]

Thank for the kind words!! I have found I can make those Carbs work alot better than anyone gives them credit for... It just takes time and a bit of effort!! Thanks for coming over.... Please Subscribe and help us spread the word about the channel!!! Andy

[@pockets5628]

Finally someone who gives the correct info about tuning using pvcr and the benefits of transfer slot restrictors! The only 4150 style carbs I have seen which come with transfer slot restrictors from holley are some 600HP supercharger carbs.

[@UnityMotorSportsGarage]

Thank you for the kind words! Andy

[@testpilot6456]

Ive been using wideband tuning on all brands of carburetors since 2005 & yes other than cold start performance ,they behave just as good as fuel injection ,provided you tune the circuits as Andy mentions . I believe Andy maybe referring " racing fuel systems " on tapatalk in relation to the transfer slot jet info. Thanks Andy for sharing this info & dispelling the fuel injection is better myth.

[@UnityMotorSportsGarage]

That is it!!! Racing Fuel Systems... There are alot of good folks on there... Thank you for the kind words!!! I love tinkering so Holley Carbs are My Thing!!! Thanks for Watching.. please Subscribe and help me spread the word about the channel! Andy

[@williamturner2617]

To Andy at Unity. I have been all over the internet studying dual four barrel tuning and Nothing even comes close to what you teach/ share. Thank you.

[@UnityMotorSportsGarage]

Thanks William.. Im just sharing what was freely given to me over the years... PLUS my school of hard knocks of what not to do.. lol I hope that you did find it helpful ! People need not be scared to try a Dual Quad setup... Andy

[@williamturner2617]

@@UnityMotorSportsGarage Dear Sir , recently, I shared a meal with a friend rinsed off the plates the next thing I know I am getting a phone call . There has been a accident with loss of life. A mother with children was only 39 years old gone and I have yet to wash those dishes and put them away !!! Why am I telling you this ? Because you have your priorities straight you theat everyone who communicates with you kindly,respectfully and share your knowledge freely even though you had to work for it. Thank you. Ps.If you want to pray her name is Tabitha and she had children and there was the driver of the other car.

[@MrTaylorTexas]

I just got my Innovate wide band installed . I'm already learning new things about the carb, and I'm even more amazed by the "pre computer" engineering of them.

[@freelancerider100]

Excellent understanding of fuel circuits! The a/f meter takes the mystic plug readings out of play!

[@frankchapa4165]

...damn that little small blocks sings beautifully!!!👍👍

[@UnityMotorSportsGarage]

Thanks for the kind words!! I sure have high hopes for project MIXED UP BOSS!

[@davescbradiorepair8195]

What size is it?

[@UnityMotorSportsGarage]

It was a 393 Windsor MIXED UP BOSS is 429CI Andy

[@blackrockbrewing5141]

I consider myself well experienced with Holley Carburetors, I have rebuilt several, used tunnel rams, built a few hotrods and raced at my local drag strip. I did not have this info, and I love that you break it down in bite size pieces that are easy to understand. Also, your resources are awesome, thank-you for taking the time to post and share this info with us.

[@UnityMotorSportsGarage]

Thanks for the kind words and for watching.. I'm just giving back what has been given to me over the years... Andy

[@jeffmiller2682]

I got 18 mpg 450 hp on a 302 ford weiand tunnel ram 2 holley 600 carbs 351 heads 194 160 valves 101/2 to one comp forged pistons a lunati cam street grind

[@jeffk6941]

I've always loved the look of a tunnel ram set up, but I never feared lining up against one ( back in the day, on the street ) because you could almost guarantee they ran like garbage. You are making me a believer for sure. Also, I love the driving footage. How about some in cab track views.

[@UnityMotorSportsGarage]

Thanks for the kind words!!! I think my second video is at the track In the truck... I love my Tunnel Ram setup... It trips people out when they see how easy it drives! Andy

[@600lwp]

I had that set up on a 350 68 camero and it got 15 as long as you drove it right but it had a 350. gear, but if you started doing hole shots and running 130mph to impress friends you could watch the fuel gage dropping

[@exploranator]

@@600lwp Time for a bigger fuel tank! :D

[@flinch622]

Speaking of looks... is that plenum cover reversed? Most manifolds are topped with compensation for engine tilt built in for level base.

[@donnatalielucasheimbigner7598]

I really miss the look of my 68 from the driver seat. If you know what you're doing with a Holley, the only benefit of EFI is when you change altitude frequently. Great to see people sharing tips & keeping the carburetor alive & well.

[@UnityMotorSportsGarage]

I know these trucks are awesome! Thanks for Watching... More good stuff to come! Andy

[@shawnbeck2303]

Andy. Never had a Hotrod. Thank you for taking me along with on this cool journey. I have studied engines and carb set ups. Just love how this engine pulls and keeps this truck moving forward. This truck just hooks up. Sitting and burning the tires is awesome. But being set back in your seat is another. Keep making videos. I will watch each one over and over again. Shawn.

[@blair79bear38]

I picked up my wide band from Innovative Motorsports back in 2006. takes the guesswork out of tuning my QuadraJets

[@UnityMotorSportsGarage]

You are so right!!! It opens up a new world of tuning... People don't know how much they are leaving on the table...

[@williamturner8422]

Hell Andy, this video ,is hands down the best carb tuning video for tunnel rams. Thank you.

[@UnityMotorSportsGarage]

Thank you for watching! I'm glad you enjoyed it Andy

[@williamturner8422]

@@UnityMotorSportsGarage That first word was susposed to be Hello.

[@UnityMotorSportsGarage]

Ummm Hello

[@happyhermit6899]

Excellent video Andy. Great information. I will surely use it in the future. Keep the great videos coming. Thanks.

[@UnityMotorSportsGarage]

Thanks for the kind words... I hope you get some great use from my tips...

[@zAvAvAz]

Hey thank you soo much for an awesome car channel and a great ride.

[@shanescrimshire8395]

Hey Andy, came over from UTG and lovin the content. Been a fan of DV's for over 20 years and super jealous of your access to the legend. I built a 302 for a 73 bronco and a stroker for a jeep zj using his principles. Both engines made me look like a hero, all thanks to him. Now I'm planning the rebuild of the 460 in my 79 f-body bronco. This one is pretty challenging. I live in California and it has to meet 79 smog standards.

[@UnityMotorSportsGarage]

Thanks for coming over and Subscribing... It sounds like you have an awesome project!! I tell you I'm very blessed to have DV as a friend and mentor! We have some great videos coming here in the near future! Catch ya later... Andy

[@MsKatjie]

I am glad Yoytube found this channel for me! Will buy Steve's book on Holley tuning for sure. Thank you, for sharing your knowledge and giving credit to the forum where you got the procedures from. Most would of claimed it as their own! Like with solid lifters and having to periodically adjust the lash; so to with a carb, initial dialing in is needed. That needs understanding and patience. The driver in the end, will be rewarded with both, " power and economy"! Cheers to you.

[@UnityMotorSportsGarage]

I believe in giving away that which has been freely given to me! Thanks for the kind words and please subscribe as I have more good stuff coming down the pipe! Andy

[@donreinholz8121]

Very interesting Holley tuning secrets Andy. That truck runs strong!

[@UnityMotorSportsGarage]

Thanks Don! Hopefully it will be a completely different animal with MIXED UP BOSS... It's going to be fun Andy

[@douglascrosby6536]

Mark and the guys (other forum admins) over at Racing Fuel Systems are sharp as hell. A lot of them also are over in the Holley wideband forums helping folks as well. Mark (and a couple others on there as well I'm sure) build custom carbs as a profession. Mark Whitener(?) I believe has "Lightning Racing Carburetors". Hella nice buy to give his knowledge away for free. He deserves some credit for that for sure!!

[@UnityMotorSportsGarage]

You hit the nail on the head, those guys are top notch forsure.. my overall goal is to show that you can get great performance and mileage with carbs, even with two Carbs!! LOL Thanks for watching and please subscribe!

[@W_R50]

Excellent channel! Just found it. Loving that tunnel ram. “That was a quick 120 mph” sweet!

[@UnityMotorSportsGarage]

Thanks for the kind words and for watching! I will keep the content coming. Andy

[@transformationclass5054]

These leaks were my issues. Thanks so much for this awesome video.

[@UnityMotorSportsGarage]

Good stuff! I'm glad it helped Andy

[@outlawofga]

I've been running the Rams for 20 + years.. But I grew up around 3 deuces and twin 4 s on low profile intakes as well... And no doubt the ram is awesome. I'm always telling people .. Forget about the bad rap the intakes suffered from in the early days. People really had no idea how to tune 1 carb muchless 2 . So the tunnel ram was monumental task for the weak of heart. But it's a BEAST when right 💪💪 !!..... Really guys . Give this baby a try. You'll love it and Prove OH Soo Many Wrong about the tunnel ram... Older guys , Will just walk away shaking thier heads in aww.

[@jeffrey4547]

u know u can get a lot more out of it we got 25 mpg out of a 327 and it had over 1200 hp on the dyno with only pump gas no nitro but that was a real expensive build and we were running right around 12.5 to 13 to 1 on pump gas and i get a kick out of people saying u can't go over 10.5 to 1 on pump gas it is actually 13 to 1 is what u can't go over or the fuel will dentainate with out spark that is by the book but if u go over 10.5 to 1 u will need to build it for it that is were the tunnel ram shines but u will need to know how to run a peddle or break lose a lot this sets the drivers apart

[@jimkillen1065]

Many years ago I ran into a little of this now where even close to this level of understanding just a butt dyno type deal . I was trying to make a 750 holly idle in a econ rail with a small block chev . The motor had a lot of camshaft , probably to much . What I did was to install some 2.5 power valves . drill a couple of .125 holes in the throttle plate to by pass enough air to bring the throttle plate back down to where it wanted them .I had seen a tech on some hot rod mag that showed how to install a piece of wire to restrict the fuel I think also in the metering block . That was a long time ago . But it make the small block engine with a 600 isk roller and a lot of cylinders idle pretty decent with a automatic . . I do appreciate your videos and will watch them all thanks i i

[@UnityMotorSportsGarage]

Thank you! I've always been a hard head as my Dad would say... If someone would say it wouldn't work... I would try my best to get it to work... Why??? I don't know... Even though I'm 41 I just love carbs.. you can make them almost rival FI in every area.. except in the Cold start... I still want to get that figured out! Thanks for Watching and please Subscribe as I have more good stuff coming Andy

[@davidreed6070]

Great job. That brought back knowledge I haven't thought about in a long time. I drill the power valve holes before I jet them.

[@oby-1607]

Sure wish I had access to the FAST Wideband meter when I was on the street with my setup. Tuning a tunnel ram with Holleys for the street is a lot different than for racing. I can't tell you how many times I had mine apart trying to get fuel economy and power. In my case, I cut a rectangular hole in my hood for clearance with no cover. It was great watching the velocity stacks shake when heading out for a cruise.

[@UnityMotorSportsGarage]

Having a wideband makes a huge difference in getting the Carbs dialed in.. when you have lean transition and main circuits the Accelerator pump circuit needs to be spot on when hammering into the power circuit! Thanks for the kind words and for watching Andy

[@derekmcdonald2856]

I have that same bit set! Got the bits and pin drill from Mc-Master Carr

[@skymit5519]

Thank you. I came for the tunnel ram, but I think you helped me fix my off idle stumble. I have a wide band sensor on mine AMC 360 and as of a month or so a go after some intake swaps and Carby tuning I developed an off idle stumble and have found the car to be lean while in the transfer slot. I have re used my metering block gasket over and over again. I think that maybe my issue. can’t wait to get home and swap that out. Thanks again. There is some great knowledge shared here.

[@UnityMotorSportsGarage]

Thanks for the kind words... If the afr is stable while in holding steady in the transfer slot you might need to work on the accelerator pumps... I ended up with 50cc pumps with the brown cam,. I hope this helps Andy

[@skymit5519]

@@UnityMotorSportsGarage Okay, Thanks for that. I have tried working on the accelarator system a bit. I went up to a 35 and have the powerblaster plate or what ever its called and used the black cam as that seemed to have the most initial pump shot according to the graph( at small throttl angles) I will keep the 50cc pump in mind if the gasket doesnt work out. I didnt think my engine was wild enough for the 50cc. Does a engi e have to be wild to need a 50cc shot? It just has a comp cams 268h cam, headers, air gap manifold, HP750 with vac secondarys. I have read David Vizards Holley book as well.(the bible).

[@markcarter78]

I did this same thing 15 years ago with a stroker windser. It works very well. You will need a vacuum guage to go along with the air fuel senser

[@bobkeller8383]

Thank you. This has helped me. I have a 88 ford mustang wit a basically stock 460 in it. I need to pull it out and replace the rear main seal so while it is out I'm going to go through it. I have a tunnel ram and two carbs for it now and am getting ready to order aluminum heads and a 545 ci stroker kit for it. Need to decide on a cam now? But this has helped me alot! Thank you. Wish you were in kansas that truck sound amazing 👏

[@robertclymer6948]

Hi Andy! Man you took us on a deep dive today sir. Excellent info and I actually understood most of it, lol. I just run a single Holley 750 on a 460 BBF, so I don't know why this could not apply to it also. Step one, I need to get me an AFR gauge and take it from there. Thanks for sharing and cheers from Motown.

[@UnityMotorSportsGarage]

Robert you are 100% correct... All of this can be applied to a single 4bbl... You will be amazed at how well it works... Andy

[@TheSlim93gt]

Nice work and info. Carbs will never meet the MPG of port fuel injection though. It makes a huge difference where in the port the fuel is introduced and good luck getting a carb to fuel cut on deceleration and cruise.

[@UnityMotorSportsGarage]

Thanks for the kind words, Carbs can rival injection but in the end I do give the edge to FI due to cold start capability.... You are also right on Carbs cutting fuel on decel... the key to that is having a properly tuned vacuum advance to put in as much timing as the engine will... Most engines can idle leaner than 15 to 1 AFR, Ive seen over 20 to 1 working with David Vizard, it takes a very strong ignition system to make that happen... Thanks again for watching and please subscribe as I have more good content coming up.. Andy

[@mattrosenboom4810]

I had a pair of highly modified 660's. My friends always borrowed them for the strip. They made awesome power! They would whistle loudly the farther you poured on the gas. Power absolutely! Mpg's non existent! More like gallons to the mile!

[@robertphillips3078]

Ur sharing stuff on Holleys that l haven't come across b4. Cheers Andy

[@UnityMotorSportsGarage]

Thanks Robert... That is my goal.. hopefully it will save some headaches and help make more power too... Im a graduate of the School of Hard Knocks University...lol

[@427_FE]

If you put a thin coat of chapstick on the metering block and bowl gaskets. it will eliminate the need to clean the surfaces of gasket material. Try it, once you do. you will always have a tube of it in your tool box! don't worry if a little gets in the small holes in the gasket. because the fuel will dissolve it.

[@UnityMotorSportsGarage]

Jeff that is good stuff! Andy

[@thorny7138]

Thank you for this! I'm working on dual carb buick 455 project and your videos have been beyond helpful. Subbed. P.S. Found you via Uncle Tony \o/

[@UnityMotorSportsGarage]

Thanks for coming over! Keep me updated on that if you need any advice just email me at [e-mail] sounds like a super cool build Andy

[@SimpsonsSpeedShop]

Great video! Man you have done some work on those carbs! Amazing. Great job 👏🏻

[@UnityMotorSportsGarage]

I hope you can use some of it to help you out. Feel free to message me on Facebook if you have any questions... Love your channel man... I'm a sucker for A bodies! Maybe one day I will have another one.. Andy Wood

[@thomasleclair7418]

,,,,,Great to find another mind that functions on an Engineering level......

[@Hitman-ds1ei]

Excellent video and explanation not to mention tuning tips, I have used a TPS so I can see exactly what throttle opening is happening also so then I can repeat it to see how much transfer slot is being used at what rpm's etc, as can take carb off and open throttle to set point and physically see slot to blade relationship

[@UnityMotorSportsGarage]

Thanks for the kind words!!! Having a TPS would be the icing on the cake for me... When you add a wideband to a carb setup... It just seems a whole new world opens up because you can see exactly which circuit is doing what... Andy

[@yeboscrebo4451]

Awesome! I’d love to acquire your skill level. Bought a crumpled 69 f250 last year and I’ve been steadily working on it. Have it looking spiffy now and I’m excited to dive into the world of tuning.

[@UnityMotorSportsGarage]

It's fun to tinker with these old machines... Hey I went through the school of hard knocks.. and I give a ton of credit to David Vizard!!! He is a genius...

[@davidandrew2610]

Hi Andy , I really enjoyed your latest video mate . Huge holley fan here , a question . Did you dial in your accelerator pump circuit , as in pump cam profiles , discharge nossles , as it also serms to be a misunderstood aspect of tuning . Thanks Andy I am enjoying your content mate . 😎👍

[@UnityMotorSportsGarage]

Thanks for the kind words!!! I will do a video on that coming up! Please help me spread the word about the channel!!!

[@bobb9615]

Awesome channel man! I’m in the process of building a 73 mach one with a set of these mounted to a weiand tunnel ram on top a BBF 460.

[@UnityMotorSportsGarage]

Most people think of tunnel rams as a race only piece.. but once you get it right, it will give you the best of both worlds!! thanks for watching, and please subscribe!

[@j.e.d.8065]

Holley carbs are nice braswell carbs are pure gold on a tunnel ram .

[@UnityMotorSportsGarage]

I LOVE Braswell carbs....I've owned a few and they work amazing! my mentor David Vizard is really good friends with Dave Braswell... Thanks for watching and please subscribe! Andy

[@Cobra427Veight]

Not sure how much advance you are getting from your vacuum advance canister but there may be more power and economy in a ecu based advance curve and with 45 degrees at light cruise .

[@UnityMotorSportsGarage]

I'm getting close to 50° !!! I have hit the lean burn limit of the engine.. David Vizard taught me how to maximize a vacuum advance... Mallory used adjustable vacuum canisters on their distributors before MSD bought them.. with plenty of time... You can get it dialed in.. I'm sure with a ECU it could have been done in Seconds! LOL... Thanks Brother for watching.. I'm planning a video on what David and I did.. It's going to be good! Andy

[@fuelseeker4823]

What is the reason ore advantage to have a Ifr in the metringblock AND later in the Main body again ? Fuel supply to the t-slot = controled with the ifr, fuel to idle have the same well, but ist controled with the ims ? I Greetings from germany

[@UnityMotorSportsGarage]

That is a good question... It's all about the area of the Transfer slot. Even though it pulls fuel from the IFR if the slot is too large it will be rich! Most aftermarket billet baseplates have the slots cut too large. I hope this helps! Thanks for Watching Andy

[@Jimmyk63]

Thank you for your insitghts and video 🙂❤👍

[@britdragster]

Hi Andy. Superb video as usual. Do you have a link to the video for the carb sync tool you made? Thanks.

[@josephnubile1970]

That Was Awsome Andy, but do you go to the drag strip first before you do what you did or after? Because every carb needs to be tuned at the strip for the best time and you will need to change jets to get the best result.

[@UnityMotorSportsGarage]

When I first went to the track I wanted to do a true back to back test.. of the Carbs.. then I wanted to run it on the Dyno in the same trim as I made the runs down the track.. when I had the 1850's on it.. it ran pretty much 12.7 and I wouldn't have to change anything as long as we didn't have a huge swing in temp... Normally I will rejet when I see about a 30 deg change...

[@marcchaffee7751]

i got better millage with 2 carbs over 1 on my 289 also . About 14 to 16 mph . Hell , my tunnelrammed 351 cleveland gets 13 mph ! But passing a GM product up hill drops to 5 . lol .

[@UnityMotorSportsGarage]

That's pretty funny Mark... Mileage does always seem to go down when you see a GM product!!! 😆

[@marcchaffee7751]

@@UnityMotorSportsGarage lol , for some reason he thought he was gonna get ahead of me ! That silly boy , not sure what he was thinking . lol .

[@michaelstrangefranke7002]

That's incredible 16 MPG I have a 2000 Dodge Dakota RT with the 360 fuel injected completely stock and I'm lucky if I get 16 MPG on the highway I think I'm around 14 maybe 15 MPG

[@UnityMotorSportsGarage]

It's funny when I built the truck gas mileage wasn't even on my radar!!! Once I installed the Fast dual Channel wideband.. I just kept messing around and kept tuning on the carbs until it drove like it had Fuel Injection... I began to notice the gas mileage and so I decided to check it one day.. I was getting around 13 mpg... I was shocked... So I kept trimming fuel from the idle and transfer slot circuit and I was able to get 16mpg!! I do have to keep my foot out of it though and that is hard to do!!! Andy

[@michaelstrangefranke7002]

@@UnityMotorSportsGarage yeah I know if I had that truck I want to put my foot into a time or 2 👍

[@terrycarter8929]

I think Edelbrock watched this video and used your info to make the new holley clone carb. It has many adjustments on it. You should compare their new carbs to the ones you have now.

[@UnityMotorSportsGarage]

You might be right Terry! I can't wait to get my hands on a set of them... Should be really good Andy

[@jbuch66koop]

Great video brother! I'll probably definitely be in your inbox with questions haha and are we just gonna sit here and act like we didn't see those slanted carb spacers????? Lmao you're gonna need to do a video on that. That looks to present a whole other bag of issues within itself. Haha well mounting issues anyway. It's gotta do something though, if you guys are not running traditional spacers. 😎

[@UnityMotorSportsGarage]

Good Catch.. I've been testing the spacers... Because I noticed on my Datalogs that on the launch the AFR would go crazy rich then stabilize.. so I found that Offenhouser made these plates for Circle track racers. I put them on and it "helped" my problem but it still isn't solved yet... I haven't noticed any major difference in driving around town though... I will probably do a video on this subject here in the near future!

[@jbuch66koop]

@@UnityMotorSportsGarage huh, thats definitely a wierd problem to have. Most cars go lean. I would think a float level issue, would bring other problems, if that was the case?

[@UnityMotorSportsGarage]

@@jbuch66koop you are thinking on the same path I was.. I did some crazy testing.. I have a good place were I could do some "testing" so I put new plugs in the motor.. went and did some test hits and killed the engine right after. I found the cylinders that were going Rich! 2/6 4/8 and that is when I found out what was happening!!

[@davidjohnson4304]

Glad to have found your site. These are the very best that I have seen. I'd really appreciate your thoughts and recommendation's on my application. I have a BluePrint 427 SBC with 220 CC heads. 10:1 compression. a .577 / .577 roller cam. It dynod at 555 Hp / 565 Trq. This is in my 67 Nova SS, Muncie M21 4 speed, Moser 12 bolt with 3:73 gears .I'd like to put on a dual quad tunnel ram set up. There's so many combinations out there, I need an experts advice. What intake, carbs and would the cam need to be swapped ? Thank you. Dave.

[@hillfurnishings]

Man I’d love to pick your brain about my setup. It’s an LS1 with duel tunnel ram and 450 quick fuel vacuum secondary carbs. I also have a wide band to tune it. It idles at 14.5, just off idle it’s 13, cruise is 14.5, lean at WOT at 15 and then 13 on decel.

[@rong4189]

Great video. I didn’t understand the power valve restriction area when you said it should end up at 73 or 74. 73 or 74 what? Is it a percentage of the main jet area? Thanks.

[@UnityMotorSportsGarage]

When you add the area of the PVCR to the main jet size (in my case im running 66 jets) At wide open Throttle when the PV is open the carb would act like it had 74 size jets in it.. So if you find the perfect jet size on the main circuit that delivers a good AFR then you should adjust the PVCR's for WOT performance... but I never hear of people doing that.. they just swap jets and then complain about how bad of fuel mileage they get.... LOL Thanks for Watching.. Please Subscribe and help me spread the word about the channel if you like what we are doing!

[@rong4189]

Ok thanks. Yup, already subscribed and spreading the word!

[@rong4189]

Ok thanks. Yup, already subscribed and spreading the word!

[@firebirdjone]

Excellent explanation, some of which I've practiced doing on my own stuff for years. When you have time, I'd like you to elaborate more on the transfer circuit where you drilled and tapped the main body. Those holes are rather large on the holley as you know, it took a 10-32 tap, not the typical 6 or 8 size that I use in the meter blocks. That's a lot of fuel to meter down so I could see how that has a huge affect on economy. All my holleys run pretty much the same way, with idle and WOT showing nice AFR's on the wide band, but part throttle or light throttle cruise is pig rich. Can't fix that with a jet change without messing up the WOT. How much did you reduce that orifice in relation to the size it originally is? I realize it's different for everyone but are you just reducing that 10%? 20%? Cutting it in half?

[@UnityMotorSportsGarage]

Thanks for the kind words... It really took some time getting the Transfer slot fuel curve dialed in... I have found that most aftermarket Billet baseplates have a WAY too large transfer slot... I have seen them be almost double the width of a stock Holley baseplate and I guess they don't understand how they can affect the fuel curve.. On some mainbodies I have been able to use ,8-32 set screws but the vast majority will take a 10-32 screw... I started out with a .079" orfice it was still way too rich... From there I went to .065" and that was WAY too lean.. from there I ended up at .071" and seems to be sweet spot.. I would say that it cut at least 40% fuel usage in that area... But it took a while but was definitely worth the effort!!! If you like what we are doing please Subscribe and help us spread the word about the channel!! Thanks Again Andy

[@firebirdjone]

@@UnityMotorSportsGarage Thanks Andy for the quick reply. Wow that is more than I expected. A #21 drill for a 10/32 tap is .159" and that hole generally isn't much smaller than that. So it's safe to guess you probably cut that nearly in half with a .071" orifice. Did you use a percentage of how rich you were at light throttle cruise compared to where you wanted to be to come up with a ball park? For instance I'm at 10.5:1 light throttle cruise, so moving to say 14:1 is a very big change. A little over 30%, so there is a lot of fuel mileage to be gained in this area. Good stuff, keep it up.

[@bobwhite5440]

@@firebirdjone i don't know the original hole dia in the carb, but based on the .159 dia tap drill and your "guesstimate" of the original hole dia, the area reduction using the .071" dia orifice should be around 70% give or take.

[@firebirdjone]

@@bobwhite5440 Thanks Bob, that's quite a change.

[@bobwhite5440]

@@firebirdjone you're welcome. i don't know the transfer slot dimensions on the 660 center squirter, but the ones on a R1850 600 CFM i measured as best i could are approx .26" tall x .024" wide which renders an area of .00624 square inches. this is smaller than the "guesstimated" hole dia i used (.134" dia) in my previous calculation. so it looks as though the transfer slot area is the metering orifice instead of the hole in the main carb body (as well it should be). so the .071 dia orifice would reduce the assumed .26" x .024" transfer slot area by about 36% give or take. these are just example values used as reference, all the dimensions off of the 660 carb would be required to calculate the % reduction properly.

[@prettyboyfloyd3397]

GOLD info Andy 👍👍👍👍

[@UnityMotorSportsGarage]

Thanks!

[@wolfspeed9043]

Your giving us gold freind!! Thank you

[@UnityMotorSportsGarage]

Thanks for watching! I'm glad you enjoyed it Andy

[@reevesautomotivefarm9614]

very much interested in the mpg content. i get 12 mpg on my 76 K20 towing rig and used to get 16 on my 69 Nova 327 340 horse but it is worn out. built it in 91. new motor 327 agian but dart block diamond pistons very small solid roller 224@.050 .525 jesel lifters. daily driver. i am that guy at Mr. B's in Rock Hill, SC that wants to talk about MPG, LOL

[@deesel666ify]

Thankyou. Excellent informative video. Nice work

[@UnityMotorSportsGarage]

Thank you for the kind words! Please subscribe and help us spread the word about the channel!

[@PaulE.Fredette-bq1zg]

What About When You Get Up In To A Different altitudes I live at sea level but a lot of places around here to go up a couple thousand feet so if I'm in Nevada I'm driving to Utah there are so many different altitude changes and temperature changes I like what you doing

[@galaxievideoproductions8783]

Awesome video! I’ve got a Weiand tunnel ram with 600s and I’m in the process of tuning out an off idle stumble/bog among other issues like A/F ratio. I’m going to try using power valve block offs or 2.5’s and I put in 76 primary jets. It’s got a huge duration camshaft and pulls about 7 to 8 inches of vacuum at idle it’s idles at 1300 rpm. I was also going to change the accelerator pumps to 50 cc. I was wondering if you could help me choose a squirter size.? I was thinking of trying 37’s as a start. I like the idle Circuit trick too. Thank you for your time and your great knowledge.

[@UnityMotorSportsGarage]

Galaxie, thanks for coming over and watching... Please Subscribe and help us spread the word about the channel. On your setup. If this is to be driven on the street I highly advise NOT removing the power valves but find the one that "comes in at the right time". On my setup I have right at 10" of vacuum at idle and I found that 6.5's worked pretty well.. you will have to see what your setup likes... On the idle stumble, I did everything Cams squirters, etc.... It wasn't until I went to the 50cc pumps my problems were solved. My combo worked really well with 31's for squirters.. the key was having the pump shot to last longer to cure the off idle stumble.. but once I did the above mentioned things I could stage my truck at slightly above idle.. 1500 rpm or so and on the last yellow just mat the throttle and that has given me my best ET to date. I hope this info helps you and if you have any more questions... Feel free to ask.. Andy

[@galaxievideoproductions8783]

Unity MotorSports Garage thanks so much! I do have 31 squriters and it was a toss up between those and the 37’s. I’ll try those along with the 2.5 power valves. My cam has sooooo much overlap it’s ridiculous. When I’m driving and come off idle the vacuum drops to just about zero. The power valves open and I get super rich. BTW I’m running 456 gears and the hesitation is only for a nano second. More annoying than anything else. Once I get past that she runs like a scalded dog. So I think jetting is ok. Thanks for your input and I’ll keep you posted on the progress

[@williamturner2617]

@@UnityMotorSportsGarage I want to thank you for helping everyone who wants to have a tunnel ram and be able to enjoy driving their vehicle. Thanks again. Will.

[@kurtgangelhoff3364]

I've liked you videos I have a 350 Chevy with a mild Cam and Edelbrock 4-barrel I would like to go with a dual quad tunnel ram setup with two Hollies could you please advise me on what tunnel ram intake to purchase and what two Holly carbs I should use as far as cfm's thank you

[@177SCmaro]

Fundamentally, this isn't that different from modern efi engines (LS, Coyote, Hemi...) except they're designed just to flow air. They all use, essentially, tunnel ram manifolds just rolled up to clear the hood. If you straighten them out and put a couple carbs on top, you'd have basically this. Getting this level of control from a carb or carbs is challenging.

[@UnityMotorSportsGarage]

It isn't hard to get Carbs to work well... They are a very Analog device that requires us to be the computer.. in fact you can get fuel injection type performance out of them. Just takes a bit of time and patience but once you get them right you are good! Thanks for Watching Andy

[@PaulE.Fredette-bq1zg]

So U Uncle Tony's garage did something similar I said they were getting like 17 and he takes you through the steps that he goes through kind of like what you did

[@mikecondoluci53]

GREAT VIDEO MAN 2 THUMBS UP, JUST SUBSCRIBED THANKS

[@UnityMotorSportsGarage]

Mike thank you for watching and for the Sub! Andy

[@f-bodyjon2189]

thumbs up sir!

[@UnityMotorSportsGarage]

Thank you Sir!

[@johnvegar9098]

@@UnityMotorSportsGarage I just watched your engine fan dyno test and said the truck has around 400 ft. pounds of torque. Another video you say the truck has 600 HP. You telling me the motor makes 600 HP but only 400 lbs. Torque? That does not seem right.

[@spyder2383]

I've had a 350 with an offy tunnel ram with 2 600 hollies, or 1 750 double pumper. Ran 4 mpg with a 4 speed and 4.11's . I've got a vdrive with a 468 offy dual wafb's, light throttle under 40 mph, not bad, wot or 70 plus mph and I think it has negative mileage. 402 chevy 2 afb low rise, 8 mpg. If you get 16 that's a he'll of an egg under your gas pedal. Lol

[@DS-es7id]

The trans did not shift when you smash the throttle, I have been wondering if that is the high stall converter that causes that type of reaction from the trans? If that is the case (if you don't mind) What type of trans, and what stall speed are you running?. It really sounds and looks like the way to go for drag applications. I( would like to get in the planning stages to put something similar together. Thanks for all the great knowledge!.

[@UnityMotorSportsGarage]

Thanks for watching, this is a C4 trans with a Manual Reverse valve body .. I'm glad you enjoyed it Andy

[@johnpino5150]

Guess with wide band I can figure it out for my application. But power valve change based on vacume signal then pump cam then jets is where I always started then if still had bog or hesitation would swap out the 30cc pumps to 50cc pumps and then back to jets. So where does your restrictions come in order of your tuning.

[@woodey028]

Andy.. what carb spacer are using? They look to be tapered. Also, are the 660s base plates aftermarket? They look like billet aluminum.

[@UnityMotorSportsGarage]

Yes they are tapered, to help control fuel slosh on the launch.. the baseplates are billet that came from Allstate Carbs! Thanks for Watching Andy

[@bobmopar2587]

Do you have a video about building a Unisyn for tuning tunnel ram carbs? If so, can you post a link so I can watch it?? Thank You

[@UnityMotorSportsGarage]

Here you go! kzbin.info/www/bejne/iYPai4ONrahmick

[@Lobo-tommy10]

This is GOLD

[@UnityMotorSportsGarage]

Thanks for Watching... I can't wait to see what I can get from MIXED UP BOSS... Which is a completely different animal! Andy

[@muskyelondragon]

Valuable information

[@UnityMotorSportsGarage]

Thank you for the kind words!

[@jesseduke694]

That's really amazing!

[@UnityMotorSportsGarage]

Thanks, It took a good amount of time to get these results.. It proved that with a wideband 02 meter you can dial Carbs in as good as a fuel injection setup! I have found that I need to change settings about every 30 deg difference in temp. other than that.. it fires up super easy and drives like a champ!

[@cabotbroughton7458]

Hello Andy, I am really liking your videos, but I would think a 2x4 would be a lot easier and less expensive to tune and achieve ideal economy and power a/f ratios throughout all the street strip operating range using carbs that have staged secondaries as opposed to the 660’s 1:1 action, or am I missing something?

[@UnityMotorSportsGarage]

Cabot, thanks for Watching.. with Tunnel Rams with 2x4's the thing is the amount of throttle opening required for a given speed is cut in half because you are opening the primaries on both carbs. The 660's have a slighty staged secondaries. You can open the primaries through the transfer slot range before the 1:1 kicks in... Even in my 4000lb truck I can go 70-80 mph and still be in the transfer slot! Hope this helps Andy

[@Rendezvous70]

What i need to know is i see people with tunnel ram & 2 vacuum secondary carbs with them converted to mechanical without a secondary accelerator pump without having a lean spot when all 8 are open.

[@UnityMotorSportsGarage]

That is almost impossible to do... On my Vac Sec carbs I tried and tried to do what you mentioned but, I found that by adding 50cc Accelerator pumps with 35 squirters and keeping the Vacuum Secondary function working! I also adjusted the secondary high speed airbleeds to start the main circuit come in faster... I hope this helps some but I will say this I love the Center Squirters soooo much better than the 600 VS carbs...Thanks for watching and please subscribe!

[@tetanustv6258]

Question. I am running 660s on a Weiand tunnel ram equipped 440. What metering blocks are you using to have power valves? Factory has them blocked and 76 jets. Any information would be greatly appreciated. Great videos, I love the detail.

[@UnityMotorSportsGarage]

I ordered 4 primary blocks for a 1850 600vs Holley.. they work great but you must modify your baseplates to convert to have 4 corner idle mix screws.. if you don't want or need the 4 corner deal you can just bottom the mixture screws out and just use the Primary screws Hope this helps Andy

[@tetanustv6258]

@@UnityMotorSportsGarage Thank you so much!! What is the modification that is needed in the baseplates?

[@UnityMotorSportsGarage]

@@tetanustv6258 it's not hard to do... But it's more involved that I can explained in a post... It would make for a good video down the road! You can find this info by googling it if you want to do it before I make the video! Andy

[@tetanustv6258]

@@UnityMotorSportsGarage Ok, thank you. Cant wait for more installments. Keep them coming and the good work

[@UnityMotorSportsGarage]

@@tetanustv6258 will do! Andy

[@armandomendoza3167]

So basically you balanced the carburetor fuel delivery system. By just adding mini jets based on the perspective of the main jets? To balance it in harmony to the fuel ratio goal? And you say you can get 16 mpg on the highway. How about in the city? What is your mpg in city driving?

[@UnityMotorSportsGarage]

Sorry for the late reply, but yes it is basically balancing the fuel system and by making all of the circuits in the carb adjustable you can dial each one in to get the most drivability, mileage, and Performance! Thanks for watching and please subscribe!

[@flinch622]

You know whats sad... my Tacoma [6 cylinder] got 16mpg around town - and its missing probably 420hp by comparison. Clearly, engineers are coming in 3rd place behind government and lawyers telling car companies what to do. But I wonder how it's different between resizing IFR from the addition of new metering "jet" [as you put it] in the mainbody where you drill/tap for the transfer slot feed? I would think they would serve the same function, or... is there something regarding idle bleeds/screw adjustability that forces this move?

[@RealDougFields]

I have 633 HP to the wheels and I get 17-18 mpg on the highway running 80-85 mph. I only average about 10-11 mpg average in daily driving though. BUT- It is a 2006 CL55 with a (modified) M113K AMG motor in it. You getting similar numbers with this combo is pretty cool!

[@davidreed6070]

Smokey yunich was in on designing Holley carbs wasn't he ,I bet David knows.

[@stuartbuckley8720]

Can you give us a address to get these jets and parts along with the tools needed to do this please. I have 2 600 cfm Holley vacuum secondary carbs on a tunnel ram that I am going to use on my 8-71 super charger on the street. I think this will work well for me. 20% under drive on a 434 sbc.

[@UnityMotorSportsGarage]

Stuart, You can go to mcmaster.com to find the stuff needed to do these mods.. You will be surprised about the improvement you can make!

[@stuartbuckley8720]

@@UnityMotorSportsGarage thank you for your response and time!

[@UnityMotorSportsGarage]

@@stuartbuckley8720 anytime!

[@terrysibley9636]

So do you trick out carbs for other people. Nice truck by the way.

[@UnityMotorSportsGarage]

Terry, I used too but it really requires having the vehicle to get the combo dialed in... Thanks for the kind words about CASPER.. You will be seeing more of it soon! Andy

[@terrysibley9636]

@@UnityMotorSportsGarage good morning from AZ. Thanks for the reply. My 306 ranger is currently apart. Had a lifter go away. Was a lot of fun for 6 or 7 years. So as all good motorheads go putting it back the way it was really wasn't an option. LoL. You know more time, more money,more of my wife shaking her head. Bottom end is at the machine shop. So we are moving forward. Combo as parts are being acquired, pretty tight solid roller, comp. We're calling it 10.8, 10.9. 5 speed with 3.73. Out back. I guess since I don't know will this be enough to even get any good out of a tunnel Ram. It's a highway star when it's on. Anyway any info is good info. Have a great day,

[@bobb9615]

Do you have and links for the drills and everything else you recommended?

[@jeffhooper7873]

Did you have to change carb body's to install power valves in sec. Side or machine yours

[@UnityMotorSportsGarage]

That is a good point... My 4224's were old and had the channel for the power valve in the mainbody. From my experience the older 4160's had the channel cast in them and the later ones have the solid flat surface. Thanks for Watching Andy

[@robertclymer6948]

I noticed your carb spacers run at a forward angle? What is the purpose for that Andy? Thank you.

[@UnityMotorSportsGarage]

Robert, I use them to help control fuel slosh on the launch... Works pretty well Thanks for Watching Andy

[@robertclymer6948]

@@UnityMotorSportsGarage Of course, oh duh me. I have a spacer I want to put under my 750. Will that change the tune? I tuned it last time with a vacuum gauge Thanks for sharing your great knowledge for us weekend hotrod mechanics. Have learned a lot.

[@UnityMotorSportsGarage]

@@robertclymer6948 it can change the tune slightly... By adding plenum volume it weakens the signal to the carb slightly... Alot of factors come into play but intake type and spacer type... Experiment and see what your combo likes... Thanks for the kind words! Andy

[@ToddWright2]

Mark Whitener's forum. It's very good.

[@davidantonio854]

I just Subbed, I love this

[@UnityMotorSportsGarage]

Thanks for the kind words and for the Sub... When I get MIXED UP BOSS in there will be plenty more like it! Andy

[@davidantonio854]

Keep these videos coming bro, no matter what keep your head up , I’m rebuilding a 1986 k10 and these are the types of videos I go to, thank you, may the Lord Jesus Christ be with you man, best regards, David