1971 'Cuda 340 Dyno Test - Thermoquad Opens Up

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[@ericball6000]

the thermo-quad was the first carb that I tried to rebuild on a 383, I was still working on it at 1am, when my Pop came to help me, I went to bed at 2am, got up at 5,30 am my car was gone, Pop took it out for a test and it ran like a champ, thanks for the flash back Dr. Nick, cheers.

[@chriswalshe499]

It's so satisfying whe you do it yrself.

[@chuckwhitson654]

Thermodrip. Why do they all leak/seep gasoline? I hate the Thermodrip

[@nickpanaritis4122]

@@chuckwhitson654 .. Once they work properly, they are great.

[@ericball6000]

@@chriswalshe499 yes it is, I like your logo.

[@ericball6000]

@@nickpanaritis4122 Dr. Nick, you are 100& right.

[@davidetchellsetchells4692]

When I was a teen, I apprenticed at the county shop as a maintenance mechanic, we had a few old Sattelite interceptors with the 400 lowdeck and of course an 850 thermoquad, at that time I knew nothing about them and had only worked on AFB and BBD 2 barrels from mopar because my friends always asked me to tune or rebuild them. The first time I saw the thermoquad, I was instantly hooked because there really is no other carb that looks like it! I never saw something so exotic in a factory car and I had to wonder if it was at least part of the reason why the interceptors ran so strong. My mentor who knew everything about all the vehicles in the shop told me that it is the most advanced carb in the shop because of the materials and the way Carter chose to design them made them far superior to all metal carbs. The phenolic resin (floatbowls/ body) was the true genius because it keeps the fuel cold and therefore makes for a denser charge allowing leaner needle and seats and less fuel consumption we were getting 5 to 10 mpg increase swapping in thermoquads and power across the board. I learned a lot from my mentor the 2 years I worked there, and it was so much fun learning about big block power because I only worked on small blocks for my friends but got big block power out of them through tuning and sometimes cam and other upgrades

[@angusandleigh]

...the fact that the kid knows what the 'Fonzarelli Touch' is, and that he's hanging around in this shop...Nick should be grooming him as his successor for when he retires.......and that his name is Nico is an added bonus! Nic's Garage

[@rickschlosser6793]

I caught the ‘Fonzarelli Touch’ quip as well. The kid is an old soul for sure.

[@jeremiahchamberlin4499]

Nico seems like a pretty chill guy. Keeps a sharp eye on his boss. 🙂

[@Welcometofacsistube]

I have 11 thermoquads. Nothing sounds better than thos 2-1/4 secondaries opening up

[@gzuzsavz]

"Bahwooooo!!!" Fabulous music, indeed!

[@badgerbait8351]

Haven't played with the thermos...just the Q-jets. Do they have the same battle cry "hawooooaaaa"?

[@bbivens8263]

On both you have to get the air door just right. A little soon is okay.@@badgerbait8351

[@antilaw9911]

I love thermoquads! Spent lot of time modding them. Out performed Holley street carbs. For starters. Make sure to adjust accelerator pump travel to maximum. No slack! The the air valve, loosen till drops (make sure to keep screwdriver tension so dont unravel) and then turn back tension about 1.5 or so after valve closes. Better to have more tension than less. My GM friends have tried them on their Rochester equipped cars and and they flat out, outperformed them.

[@michaelcowan6254]

Totally agree with you. When the idle acts crazy, it's usually the accelerator pump. Also, check the air door for bogging issues. A little adjustment one way or another makes a big difference.

[@carterthermoquadclubmanley1863]

Gm small blocks LOVE 850 cfm tq's

[@joebacarella2829]

Good looking nephew Nick, I see apprentis in his eyes, I thought thermoquads were in Chevys, all of my Mopars had Carters, then again I didn`t own one after 1970, My buddy had a 71 Cuda 340 auto, I didn`t know the stock HP, the Cudas were great with 340 or 383 they weren`t too nose heavy, I think 340 `s handled the best, it sounds great Nick.

[@davidetchellsetchells4692]

We all learn things over time, as far as I'm concerned you are the best mopar guy in the industry, if I ever get rich enough I'll have you build a few of my dream builds like the 1000hp 400 lowdeck with 426 hemi crank with long rods and special raised pin pistons from Keith black. Another one is a 360 with 340 forged crank, forged rods and high domestic pistons that runs 8000 ram all day and produces 700 hp basically an early 70s Nascar engine. AFR heads, custom roller cam, timing belt instead of a chain, electric water pump and a custom sheet metal intake that I build with a holley 800 cfm carb

[@Anthony-nw5zv]

Always liked the way thermo quads work and sound.

[@jimcear1766]

Great to young guys learning the basics, air , fuel , spark

[@wokewokerman5280]

...and timing

[@terryzeissler4199]

Nick I love your dyno videos and testing a 340 which has always been my favorite engine. I did my apprenticeship in the 1970s and specialized in tune-up electrical and diagnostics. The number of thermoquads I have overhauled and tuned would probably in thousands. As to your lean condition the metering rods came from the factory set to low. There is a screw adjustment on the power piston under the red clip that you can adjust to clockwise to raise the metering rods to richen the mixture . do this at 2100 rpm. As you raise it the engine rpm will increase. I always set it to 1 1/2 % co at 2100 as my Allen Smart Scope had a 3 gas analyzer but did not give A/F ratio. The other problem you have is that your air door spring is set to loose. You will probably have to tighten by about 1/2 turn. Also on the street the accelerator pump needs to be adjusted to give about 1/32 inch more stroke than what the spec is. One other thing you can do is install a quick curve kit in the distributor, the factory curve is way to slow. Unfortunetly Mopar no longer sells this kit but a Mr Gasket kit might work. As for the not returning to idle check that the secondary plates are closeing completely when you go back to idle.

[@nickpanaritis4122]

Yes, I always have checked the base gasket not interfering with the throttle plates. And for the info on the carb, thank you. I have another 340 coming in the future that will be needing help again. Every part of the carb needs to be tuned for performance. So from what your saying is, they were not perfect to start with. Thanks again Terry.

[@richardmoerke9329]

Yeah! Those TQ were like that. Then you got a cold day thing ran like crap the next day was a killer. Driving along just stat running good. I got rid of it.

[@jeremiahchamberlin4499]

You really know your Thermoquads! I’m impressed. I’ve made attempts at tuning, bought books on them, etc. but most of the adjustments you cite so authoritatively weren’t even mentioned. Kudos.

[@oscartheg6674]

It acts like most fords it has to be warmed up you just have to be patient with it.

[@BrandonLeeBrown]

The poor man's quick curve kit for Mopar distributors has been to remove the short, thick, heavy limiting spring from one weight in the distributor and leave the long, thin spring on the other weight. Then leave the vacuum advance disconnected, as it would be too much when used with the quickened advance. The Mopar and Mr. Gasket curve kits have 2, short, light springs, which cause full advance to come in right around 3,000 RPM, which is good and quick. I worked at a new automotive electrical shop in 1979 called, "High Volt", but because we charged real time and the vehicles we got were very old, with electrical problems, we had to switch to general repairs in 1980, but those old cars weren't worth what we had to charge in 1979. The original Mopar Performance engine books mention the distributor curve modification I mentioned, along with the option of using new Mopar Performance springs. The first time I tried it, I had planned to replace it with the MP springs, but it worked so well, I left it with the one original spring.

[@Knards]

I had a 72 Duster 340 with the 7.62 Thermoquad. It was like flushing a toilet when that thing opened up! Loved that car

[@timcornock8232]

Someone gave me a '67 Charger back in 1992 (still have it, in fact), and I got tired of rebuilding the leaky old 2bbl on the 318, so I picked up an Edelbrock Performer, and a funky looking plastic carb from the wrecking yard. It was a completely different car with the TQ, but it wasn't until some punk in a Jetta tried to get around me on a freeway on ramp that I realized that my dual throttle return springs were so strong that I'd been driving for two weeks on the primaries. I mashed the throttle and the whole car seem to vibrate, and I backed off before realizing that it was actually the howl from the secondaries. I floored it and dropped the Jetta. I had so much fun with that car before the 318 died that it'll be hitting the road again soon after 20 years in the garage with a warmed over 360 - and the very same Thermoquad I put on in '92.

[@charlesbeaumont1675]

Nick is like an orchestra conductor - every note is perfect

[@buckykattguitar]

I was sitting here yelling "stuck float!"

[@tommontague5721]

yep!

[@TonyMancini-js2br]

Me too

[@pb68slab18]

I was thinking no gas in the tank.

[@wokewokerman5280]

or the pump seals are dry....gets better as they soak

[@mynameis9057]

I know you don't like headers Nick, but it's good for another 15+ h.p. boost and a lot more on the big blocks as you've shown. For this 340 to me, it'd be worth it. Except for factory original cars that people want to keep that way, almost every 340 I've seen and worked on over the past 30+ years, they've almost all had headers on them. Believe me, I love factory original cars, but if it helps to get some more power and can be changed back to original without damaging anything, I usually get them. Then again, I'm the type of guy that shoehorned a 440 with the 727 attached, and put headers into my 72 Barracuda all by myself in the driveway! Like you,if it has to be done,if even by myself alone, I used to get it done!!! That was in the 80s many cars, trucks and moons ago. Thanks again Nick and company. Great to see the younger generation learning about engines with you too!!! He can have no better teacher!!!😁👍

[@randylear8264]

My first experience with a thermoquad came in the way of a 72 340 Duster 3 speed on the floor with 3:92 rear gears. It belonged to my younger brother. I also owned a 72 Duster. Mine too had a 3 speed on the floor and rear gears of 3:23. But mine was a 318 that we added headers, 4 bbl. Edelbrock intake with a 750 Carter avs off a 383. Also cam dynamics cam and recurved distributor. That thermoquad carb when set up right was killer. It stayed in tune and delivered great performance results. We played with the rear air flap until we had it perfected. When that 4bbl came in with first gear the tires would light up at any speed in first. In second it would break traction for just a second or two. We never had to set it after the adjustments were made. I own a 340 today. And I still have a stock cast iron intake with a thermoquad carb ready to drop in when I get tired of the avs that’s on it now. But I also like the 750 avs. Great reliable carb in its own right. Great video Nick. Long live the 340.

[@mikenomath3897]

Back in the late 70's i picked up a Charger 440 RT with 45K miles on 'er for 2 Hondo'$, top over hauled the Thermoquad (first time ever) fired right up rant clean, drove off into the sunset! :) They are somewhat more complex than Holly'e or even Quadrajet and just as fickle at times! GodSpeed Nick! Carry on!

[@kevinharms7578]

I had a 71 Road Runner 340 Air Grabber, with a Thermoquad , I loved that carb. The secondary air door needs to be set firm.

[@antilaw9911]

Exactly 👍

[@kevinbrucestevens7747]

Nick you are a Master at your craft. Shows what hard work and some smarts can do.

[@jimmungai1938]

If it was me, I would check the bolts that holds the carburetor together the bottom plate in the top part of the carburetor. See if they need snug down some more remember you got 2/2 there that have the potential of leaking vacuum. This is six in a row Jim from Kennerdell Pennsylvania

[@Mr.mopar71]

71 340 cuda, I have one sitting in my garage. 😁

[@ronjones-6977]

After getting a truck to run AND drive these last 2 days, after 5 years of being totally parked, I'm in the right place to relax. Sing the song of my people, you sweet little 340. You are my all-time favorite engine....EVER.

[@davidlibby5430]

I was a carburetor mechanic back in the seventies. When this issue would happen, we would rev the engine to 3500 RPM and then shut the choke for a second or two and then let the engine catch up to clear out the excess fuel. Sometimes their are particles in the metering system and this would purge them out. Hope this helps.

[@wokewokerman5280]

not only junk, but dry seals that needed to swell a little..

[@terryzeissler4199]

The most difficult part of setting up the thermoquad is the settings for the choke and pull off as it involves multiple steps starting with the distance from the bottom of the throttle plate to the hole in the choke rod lever. If not correct all the other adjustments are out. This is important as the pull off also affects the secondary air door opening. If you tap the air door with your finger it should close all the way every time with just a little bit of a snap. I have the special carter tool for the lock ring that is hollow to allow a screwdriver inside of it to turn the spring adjustment, but you can also do it with a large screw driver for the lock ring and a smaller one for the spring adjustment. Properly adjusted the TQ gives you the best of both worlds, exceptional fuel economy for everday driving and cruising with instant throttle responce when you floor it and great horsepower. You have to love it when those 2 1/4 inch secondaries open up and the great roar that came from them. 1972 340 Rallye I had back then also had the air cleaner with trap door at the back that would open at the same time and add to the roar of the air rush. I could pull away from any Camaro and leave them behind and still get 25 miles per gallon 75 mph. With just a few tweaking adjustments this 800 cfm carb performed flawlessly on all engines from 318 to 400 cid. The 440 got the 850 cfm version. Just as a note the 71 TQ was known as the solid fuel version and was used just the one year. It was redisigned for the 1972 and up and was even a bit better than the first version. Looking forward to the next 340 dyno session you have comeing up.

[@nickpanaritis4122]

WOW. Thanks for the info.

[@bobgrim9605]

What a nice 340 ! The early thermoquads were excellent carbs. It pays to read the manual because once sorted, it will perform like fuel injection. Great job Nick, and I'm glad you're feeling, George.

[@davef.2329]

In proper tune, that carb worked very well.

[@jerryhatrick5860]

That's any rock heater carb imo. Especially thermo and the quadrajet. Old man's garage has a recent dyno test using a car and fi. The car made more horsepower tunes right. Very good watch. Oh on a 5.3 ls. Tried a single plan and a dual plane intake the single okabe with e85 and a car ruled. 430ho. Torque for days and an seven crossover between hp and tq

[@gzuzsavz]

"...like fuel inj" yup. Mine..once the car was started & ran for the day..i could just reach in & hit the key.. boom! running. ahaha. ppl freaked out. it was a '75 440 cop car mill that came in my 1st car in '84.. a '71 Satellite 2dr. after that, same mill in a '66 Newport and a '70 Fury Coupe :) that dang engine served the police..subsequent owners, and then me..decades of high winding use. but..i changed the oil ever 3k mi..always good Texas oil..10w-40 or 20w-50..depending if winter, or summer. Mobil1 from about '86 on up.

[@wedge4hire]

I'm commenting before watching the video! I had a '71 340 Demon w/Torqueflite. The 68-71 340's were jewels!! Mine spun a main bearing at 105K and after giving it to a clown to rebuild, it never ran the same, so I sold it. Rated at a ridiculously low 275 horses, they were actually putting out about 320-325!! I expect Nick's know-how will add 10-15 hp to that! The man is a magician on Mopars!!! Now i'll enjoy the video!!!

[@gzuzsavz]

some 68's had extra hot cams..esp 4spd cars. & deffo anything prior to '71 had a bit more beans..some mills saw comp drops..others were detuned via timing or w.e. the 340 and 440-6 and 426 Hemi hung onto most of their CR in '71..the 340 only losing 3 tenths..from 10.5, to 10.2.

[@wedge4hire]

@@gzuzsavz Good info on an outstanding powerplant! They called it the, "baby Hemi" for good reason!!

[@gzuzsavz]

@@wedge4hire Thanks! Yeah, she is a lil beest, for sure.

[@scottbatey3130]

Now, besides all the experience and skill. Nick has The fonzarelli touch!!! I love to see nick and nico working together!

[@kavinskysmith4094]

Hey nick I thought you might find this funny, I was watching the car starz video guy, and just for the hell of I checked the challenger one from vanishing point, apparently some of the cars werent originally white, they were actually green like your actual car, it shows up in one of the scenes in the desert as theirs a quarter panel dent, and you can see the green underneath it and it looks to be the same shade of green you found your 440 in so your vanishing point clone is actually more accurate than you realize and you dont need to feel bad about respraying it as it is now just even MORE movie accurate lol

[@hawkuser604]

I was taught by an old timer years ago a few tricks with spread bore carbs including the one with the rag (or your hand). One was that if you flooded it was to prop open the secondaries with a screw driver and crank it to clear it. Sure worked on the Q-jet. I love the spread bore carbs.. It was cool to feel the hard spot in the throttle on a Q-jet right before the secondaries opened up and the trans down shifted!!

[@grantlee2975]

Hi Nick I have played with these carbs since the mid 80s and have had the odd one with secondary butterflies with a sticky throttle shaft and don't close fully after full throttle, that was the problem when you had high idle after full throttle . I have just finished a 318 mild build with a Thermoquad and its running sweet , and with no choke it will start after 3 days without touching throttle, though it is summer in Sydney. I do love these carbs for street use, good cruise economy , power and sound when opened up.

[@EasyEd1955]

Hi Nick & Crew: Love the show, it is unique on KZbin. This 340 build reminds me of my wife's (may God rest her soul) '74, 318 Gold Duster. It had the same/similar two stage carb. We live in Nashville,TN, and in winter mornings were 15F warming to 40F around 3pm. Anyway, I drove it and learned how sensitive and lean running it was. Never had a carbon encrusted spark plug @ replacement intervals. The 340, right at the start you took the primary choke butterfly valves off-line. I believe they serve a dual purpose. They close completely on cold starts, but they close partially at idle. I noticed this with my instruction to this carburetor on cold nights leaving work. It was at the cusp of normal Temps but not quite. If I so much as removed the air filter cover momentarily, the choke should flip open (that partial I mentioned) and I'd be screwed. Needing to work the throttle until warm enough to idle. I think your rebound problem is connected to the primary choke being held open, causing a lean mixture.

[@yianniyianni8158]

Be careful with all those paint fumes when breaking in those engines Nickos maybe run some extra ventilation or wear some kind of mask. Great job once again keep safe best regards from Down Under Australia

[@themacgyverinstitute5340]

Liking the Thermoquad❤️❤️❤️

[@brianhdueck3372]

Great to see you back George! Healthy George and a healthy 340. What could be better!

[@user-ls7yi1vw5m]

Says a lot about Nick that he not only admitted his mistake and showed the correct way, but gave full credit to the carb guy for a perfect job. You can believe him, that's why people like him so much, it's honest

[@archieguitarz4700]

Not surprised it's running lean at idle. My '72 340 with a TQ was very lean from the factory and had to richen it up to get it in the ballpark. Also I noticed the secondary air door seemed very loose earlier in the vid but didn't seem to be an issue when you did the pulls. Thermoquads run like a champ when they are dialed in.

[@Orcinus1967]

"The Fonzareli touch". Wow Nico, that is a blast from the past! And not even your past by a long while. Indeed that is what the Fonz would do. Very apropos.

[@antilaw9911]

I alsobused the black phenolic 1" carb spacer on my 440 to help keep it real cool. The spacer i had was on one side molded for a spread bore. The other for standard 4 barrel. I highly suggest using that. You can learn to master the thermoquad if your patient. Its not difficult. I drilled all my jets 1 size bigger on drill bit. Did all the right adjustments and ran so crisp and flawless with no stumbles or lag ever! Also, there were 2 thermoquad styles, lean-burn(with lean burn vacum port) and non lean burn. Scarf these up for cheap at swap meets then use the best non warn parts from them to make one great one.

[@jamesmackinlay4477]

Thermoquads are actually great carburetors I ran a lot of them back in the day. What their main problem was is the plastic middle section cracking a lot of time internally most the time causing vacuum leaks and all kinds of problems. But once you have a good one and have the jetting kit rods etc.. they were very good drag racing carbs. I routinely ran low 11s and high 10s with thermoquads.Offenhauser Port-O-Sonic intake with the epoxyed Popsicle sticks in LOL. with a built 340 in a Duster. Did some 440s to like that to with different Intake though. I ran them just to be different from everyone else. I have two of them NEW in the box still in the factory plastic in my garage bought them in 1978 one is the same carb you have in this video and the other is for a 400 big block for a Roadrunner I think a 73 400 engine. Anyway great video as always Nick and crew.

[@badasscaddy]

Yeah, and the center section would warp often too! I think when the engine had backfire issues, that's what caused the cracks. Say, what were the popsicle sticks for that you mentioned?

[@jamesmackinlay4477]

Sorry for the late reply those Popsicle sticks got rid of some turbulence on the floor in the plenum of the intake and increased the velocity of the charge to the intake valves thats what I was told back then. I just followed the Direct Connection engine manual instructions and let it rip. It did pick up a tenth in the quarter sometimes a little more do it did make a difference.@@badasscaddy

[@claytonandrews251]

When tuned correctly the thermobog was a decent performer . Great fuel mileage if driven correctly.

[@69Dartman]

I used to take the 318 that was original to my Dart to 5500 at the WOT shift point with the stage 2 shift kit in the 727 I swapped to. I had a 9800 aftermarket Thermo Quad, love them and I do have a strip kit and plenty of spare carbs and parts.

[@TonyMancini-js2br]

I've always liked the sound of the thermal quad carburetor back in the 80s diplomat police cars they sounded amazing.

[@blau325]

I have rebuilt a lot of thermoquads. I run them exclusively on my 72 Charger, it will not run without a choke even in Florida. Sounded like the needle and seat were sticking. They are finiky but they are the best street carb.

[@BradVandrasik_music]

This was a fun flashback. I inherited the 340 gene from my dad, and, for a too-short time, in the early 90s, I owned a 71 Demon 340. It was the first, and so-far only, time I did a cam swap and top end work. I tell you, I was more nervous firing that up for the first time for the break in than I was at my wedding! Luckily, it went smoother for me than for Nick here!

[@scottscott6794]

Always enjoyable watching a master at his craft. Thank, you Nick.

[@NicksGarage]

Glad you enjoyed it

[@wokewokerman5280]

...he's a human torque wrench!....

[@herbferguson]

The 71 factory 340 intake was the best one. Last 3 numbers 100.

[@nickpanaritis4122]

I did not know that. Cool.

[@joelmurphy7980]

Never met a T-Quad that I liked. Back in the day I'd install the Mopar throttle lever on a GM Q-jet and toss the T-Quad over the fence. The neighbor would promptly toss it back because he didn't want it either.

[@carterthermoquadclubmanley1863]

They are not for everyone...🤣

[@davef.2329]

From decades-old, possible flawed memory, the distributor vacuum advance nipple was always connected to the "ported source" (shown plugged here) nipple on the left front of the carburetor whereas the nipple at the rear of the carb, that it is connected to here, is manifold vacuum. Don't recall ever seeing that on these early non-emission control TQ carb engines. A minor linkage adjustment likely is hanging the secondary throttle plates open very slightly after a wide-open excursion of the main throttle rod. The relation of the primary choke rod is very critical to that whole operation, as the secondary throttle plates are blocked closed when the choke is on any little bit, and that can work to the opposite when not adjusted correctly. We battled and solved many-a Thermoquad issue right out of the factory back in the day thru good old trial and error. God, I'm old... Efaristo, kai na eisai panta kala! PS: Wanna talk about needle seats for the floats backing out in the cover, and other anomalies? Let me know... lol

[@taylorsrus9543]

He pretty much always hooks up the vacuum advance wrong.

[@wokewokerman5280]

...wish I had today's tech when I tuned these carters, especially on a dyno at RPM....our dyno was asphalt and rubber....

[@davef.2329]

Amen. @@wokewokerman5280

[@carterthermoquadclubmanley1863]

Abother issue being the pass side bowl vent lever adjustment...if way off, holds the float down and you get a mild flooding cause tge needle is not seated.

[@davef.2329]

Yup, Forgot about that one! Too many darned decades ago... Seems like there was some jet wells on the bottom of the phenolic bowl assy. that started seeping and needed epoxy on these when they got some years on them.@@carterthermoquadclubmanley1863

[@wokewokerman5280]

Fun the scurry around a new engine....every time gross tuning, paint burnoff, and big time listening...

[@TheFRiNgEguitars]

Nice little engne, I have said this to my nephew and others, the tuning is critical on any performance engine, or stock engine like this one. if only more DIY-ers and mechanics knew how to set up the automatic choke. For a manual setup, the choke pull-off eliminates jogging the choke.. and the engine will start up and run on the first or second compression stroke. If the engine doesn't start right up, the choke isn't set up correctly. One pump on the gas pedal, wait 2 seconds, crank and it will start and run by itself. The exhaust damper is essential for faster warmup, always a mistake to remove it. And fellas, a street engine prefers at least a 180 degree thermostat. The pistons round up, and your engine will last longer, no worn skirts, no blow-by. Your engine will love you, and serve you for the long run. Never run a street car without a thermostat, (or run hard when cold) fatal mistake. I do think this engine would benefit greatly by a stiffer cam, maybe .488 lift at the exhaust and 230 degrees duration, for the top end that these engines are capable of. The cam I suggest would have a slight chop at idle, good vacuum for power brakes.

[@davidetchellsetchells4692]

2 other notes I want to pass on to you Nick, the choke linkage is designed to Stop the secondaries from opening when the engine is not fully warmed up, to me this is absolute genius on the designers part. Also that tiny screw in the middle of the airhorn between the primary and secondary ventures is the master mix screw for the primary rod height . So if you ever do have a lean or rich problem in the primary circuit you can easily adjust the AFR with this screw while the engine is running! Another genius idea from the Carter engineers that I find works as good as fuel injection or shall I say is as reliable. I look forward to more shows with thermostats involved because in the 70s into the 90s that was the go to carb for mopar fanatics like me who actually studied the thermostat and really all the great mopar carbs that were used on in my opinion the best engines Detroit had to offer at the time

[@nickpanaritis4122]

The 1972 Blue Duster with a 340 will be Dyno tested with a Thermoquad. This time we are starting the engine with the Choke set up completely intact. just like it came from the factory.

[@fubarmodelyard1392]

Beautiful running, sounding and looking 340. That choke well was genius

[@scottrance-im7xz]

I will add to my prior comments that the thermoquad was an emissions 4 barrel . Lean primary operation was built into the carb . I always ran into lean running on these carburetors and the rag on the carb covering the airhorn completely and engine is not choked off tells the tale . Scott in soca

[@myleghurts3546]

Best combo ever! high revving small block is lighter and car handles better with same tire torching power from Nick's magic. Welcome back George😀

[@NicksGarage]

Right on!

[@kwhite145]

I had a 72 340 Challenger loved it!

[@billholemo2518]

In Baltimore,my friends Dad had his parking place in front of his spot occupied by someone . He ran a hose up from the cellar and hosed the car down for several hours out his front window. The interloper came back in the morning . The his car was frozen under 6" of Ice!! It took the interloper 2 days to chip it out!! Never saw him again.. 😂😂😂😂😂

[@greasyhitchball]

Finally, we have some true horsepower numbers on these legendary motors. Lot of B.S. out there.

[@kevinnobody3052]

When I was a young guy without a clue about many things, I had a 71 'Cuda with the 340. The car came from the factory with the Shaker hood I loved the car but didn't really know what I had and I sold it. I've sold other cars thru my lifetime that I liked but the 71 'Cuda is the one I should have never sold.

[@cuda426hemi]

They weren't that nice - the doors were heavy rattle traps, E bodies were too damn heavy and just couldn't turn. They were cheap too, we went through Mopars like socks as kids. The car I miss more than my 'Cuda is my '69 Coronet 500 coupe - that's more rare and could handle better than any E body. 🚗

[@menone8532]

​@@cuda426hemievery car back then handled like a soap box derby car, taught you how to really drive. My daily driver has rack and pion steering. I like it if I'm going down the interstates, hate it while just going somewere locally, too touchy for an older guy that grew up driving stuff with Saginaw gear boxes, ya can't rubber neck a back yard if you see a classic what ever running a rack an pion, you might end up in the ditch.

[@cuda426hemi]

@@menone8532 I hear ya. We didn't drive so much as set a course and let the QE II suspension do the rest LOL. First time I ever drove rack and pinion I forget what..Rabbit? Scirocco? I thought Oh! Steering! What a concept! 🤡

[@menone8532]

@cuda426hemi rack and pion, great on a street car, scary on a lifted truck running 33 inch tires, back roads, ect. I rebuilt both Saginaw steering boxes on my Scout's and they steer great with big tires. I can run 80-85 down the interstate in my spring over IH Scout with 33's without any issues.

[@cuda426hemi]

@@menone8532 what year Scout?

[@joeljenkins2876]

George!!! Glad to see you doing and feeling BETTER!!! This brings back memories of my carb rebuild days, and having to set choke pull-off and unloader adjustments. Love Nick's persistence to get the job done, and done right. Kudos all, and great week to you!!!

[@davidlibby5430]

Yes, I've done a few hundred in my days too, back in the seventies. Do you remember the Variable Venturi carb from Ford? They we fun-----ha-ha! We had to do the entire fleet of Police cars in my town. All Crown Vics!

[@menone8532]

I did 2 of them, told the boss never again.

[@anthonycadiou8367]

People are seening now how touchy a carb can be. Good work Nic Good work George

[@craigcontofalsky4387]

Well I've been driving and racing 1971 340 engines since 1971. That is not a 71 Thermoquad. Probably a 72. The 71 carb has idle screws at an angle. Also the choke linkage is on the end of the choke butterfly outside of the airhorn. Plus the 71 doesn't have the screw adjustable piston on the metering rods. The accelerator pump should have more available stroke. I can send you a picture of a 71 carb. The exhaust manifold on the left side (passenger) is a 70 or earlier, too. Hate to nitpick but not original stuff. Yes I'm 71 years old and happy to help.

[@moparcuda1]

Your right about the carb,this is a 73 -74 carb

[@69Dartman]

The 71 and earlier are unique and even harder to find parts for so better run the later versions before the smog tweaks really screwed them up. I used to have several early ones and a new strip kit but I sold them when I bought my house and a Mopar carb rebuilder wanted them. I still have a later strip kit and plenty of early and later ones on hand with plenty of spare parts. I run a 9801? on the original 318 in my Dart, best carb it ever had and can be very smooth and reliable.

[@WilberWiley]

I HAD A 340 IN A 69 DART. I LOVED THAT CAR.

[@greggsvintageworkshop8974]

Yep, brings back memories of the good ole days and my first cars back then. Great video Nick and George, she runs like a Swiss watch!

[@dennisspangrud6850]

Nice to have a 340 on the Dyno.

[@NicksGarage]

Yes! And more to come.

[@quickdHemi]

Adjust the metering rod tree! Small flat blade screwdriver, turn clockwise to lift the metering rods up to richen the primaries!!

[@scottrance-im7xz]

The mighty thermoquad . CHRYSLERS answer to the Quadrajet . I've worked on many of these carbs over many years. The plastic phenolic center bowl section can and was alot of trouble as these carbs aged on hot engines . Remember this carb was also used on the terrible Chrysler LEAN BURN engine control systems . The engine heat really was the enemy of the thermoquad and warped the center phenolic bowl assembly . Like them when they work , hate them when They don't. Id only run that carb if you absolutely had to have the car and engine completely original . Nick fighting tha5 darn carb brings back many memories of m6s3lf do8ng the exact same thing ... 😮 Scott in soca

[@JUNKEdDudek]

Thank you! I really enjoyed it. Wat to go Niko!

[@zadmiral55]

Thermoquad was the best carb I ever had. Had a 60 over 360 that ran like a scalded dog...460 hp

[@robertorhymes]

It's far from a wreck This factory fresh rebuilt 340 belongs to Carole from Quebec and it's undergoing a thorough Nick's Garage check Nick and Niko have to break in the cam but a starvation of fuel wasn't part of their plan If anyone can fix it Nick's Garage can Thanks Nick Niko and George Big shout out from London

[@trickster8635]

Thermoquads - notorious for top cover warping and allowing air leaks.

[@FreedomRock44]

Yeahhhhhhh the manifold paint went from silver to bronze!!!

[@PatandDoopypoopy]

A good functioning thermoquad is a great carb. Same goes for quadrajet carb. However- both are similiar in bad attitude when acting up. Makes you want to throw them in the scrap heap(dont do it- save until one calms down then go about FIXING it.) Thanks for great content. Health and Wellness for all.

[@NicksGarage]

Thanks for watching.

[@4ondflor]

Man that’s a lot of snow! I’ve never played with a thermoquad but it seems they like the simple mechanical world. Electric chokes are nice, but there’s something about the old mechanical setup that’s just easy to understand. Thanks for bringing us along on this one, I hope everyone is feeling better.

[@richardmoerke9329]

We have some snow which was not bad. Like 13 inches. Then we got the wind! BUT WOW!! You got some snow. The last 2 wind storms we got with that much snow I would not be able to get out of my house. Good luck Nick and glad you’re feeling better. I hope you get that killer 6 on Dino soon.

[@eugenecastles7475]

Hi Nick & George, I Hope that you are feeling better now that the weekend has passed. I love seeing the 340 on the Dyno, and was very impressed with the numbers this stock rebuild made. The Chrysler engineers knew what they were doing, and the numbers don't lie. I loved the video, and am looking forward to the next 340 on the Dyno!

[@NicksGarage]

Thanks Eugene. Feeling much better now.👍

[@johnrmercer4244]

Mr.Castles Sir, did you ever get your ground pounder back into the great state of Texas from Mr.Nick? Did you guys ever make a Texas delivery video so us northerners could enjoy you getting the Texas asphalt use to those new skins.

[@eugenecastles7475]

@@NicksGarage So glad to hear that George, you can't keep a good man down. We are in the flood mode here right now. We had over 3 inches of rain this morning, with more expected overnight. We do need the rain badly after last summer.

[@joebacarella2829]

How`s that Charger 500 doing Eugene.

[@mariorabottini5687]

Well done Nick! It’s so awesome to see a master of his craft….doing exactly what he loves! Cheers from Melbourne Australia!😀

[@timbutler8316]

Nice Nick! Another one done. Thanks again we all enjoy seeing the next one on the dyno. 340s are awesome, mighty little engines. Thank you George! .

[@nickpanaritis4122]

Hi Tim. The other 340 is going to be tweaked a bit. 1972 340 Corporate blue.

[@J.W.W.]

That thermoquad is bringing back bad memories of the carb on my 440 back in the day 😆. 76 Dodge Coronet Persuit

[@NicksGarage]

Gave you a rough time?

[@J.W.W.]

@@NicksGarage sure did, until I spent a very careful day doing a complete rebuild myself on the kitchen table instead of relying on others.

[@J.W.W.]

And as I watch the video, I see Nick is having problems with that thermoquad also

[@larryburns4605]

When Thermoquad is right they are great carburators

[@Westcoastride]

Floats would get saturated and flood the bowl.

[@chriswalshe499]

I so love yr vids Nick and crew. Look forward all week. Great to see Nico- I knew it wasn't a passing phase with you buddy. Good onya.

[@moparnapalm]

I worked with thermoquads for many years.....theres several adjustments.....i see two thats fighting you here....the spring tention on the rear air vane isnt wound tight enough...changing the tention can fine tune the mixture......the second is the needles....a small screwdriver adjusts the hight of the needles....whoever rebuilt that carb didnt properly set the air valve tention and set the needles to the stock height....

[@skeptic3332]

WOW had to do a double take. Nico sure looks like the Fonz. I think he might be Nicks favorite Nephew because I've never seen him let anyone else touch his dyno.

[@user-hi2ev7ug4l]

Great job Nick....nice to a Thremoquad on the dyno...good content and thanks

[@NicksGarage]

Thanks 👍

[@user-jc1km6fr7v]

Hey Nick, Greetings from Hong Kong. Thanks for another great video.......a little taste of home while I'm on the other side of the world. My Cougar is in Napanee Ont for a new paint job, looking forward to driving it back your way.

[@NicksGarage]

Cool!

[@MikeJBlues]

Another great Monday,love the 340 👍

[@NicksGarage]

Thanks 👍.

[@craigcontofalsky4387]

Nick, one last thing. I believe the idle speed for the 71 340 engine is 900 rpm. It's too cold to go out in my garage and check. It's on the emissions label on the inner fender. Should be in your old Chilton books. They're pretty accurate. Sounds good. One last item missing is the idle solenoid. It sets the idle and the carb screw you're using is backed off a turn so it doesn't diesel when you shut it off with the 900 rpm idle. It let's the primary close completely.

[@mikek5298]

That should be, "I'm too lazy to go out in my garage and check". That is, if you even have one, which by your reluctance seems entirely unlikely.

[@nickpanaritis4122]

I totally agree with you.

[@craigcontofalsky4387]

Well I did check and I was right. 900 RPM ​@mikek5298

[@dannypeter6565]

Thanks for the show Nick and crew. You guys have way more snow than Edmonton. Stay safe. Cheers

[@oops1952]

Thank you Nick👍 My old direct connection book said the NHRA factored the '71 340 at 310 hp. Back in the day premium pump gas was about 98 octane which helped

[@danielroberts698]

With headers it would easily get 300 horses. I put headers on mine back in the late 70’s and it felt like a new engine. I couldn’t believe how big of a difference it made.

[@weshilton6862]

That big spacer under the carb is important too!

[@pseudopetrus]

These guys love their work!

[@bdogjr7779]

Awesome Nick & Niko《☆》I like 340s with stock HiPo exhaust manifolds👍🏾🥤🤳I put a manual Choke on my 73 Dart Sport 360 when I upgraded to a bigger Carburetor. Welcome back George✌🏼😎☯️

[@meowerstationone3793]

Hope you're feeling better George. Thanks for the show guys!

[@NicksGarage]

Thanks Meower. Lots better.

[@jacques.formateur0060]

Yes we happy the camera guy is back🙏🙏😉 And hello Nick ✋

[@davidetchellsetchells4692]

Your thermo quad guy should have told you that you cannot hold the choke open with a zip tie because that locks the front and rear barrels together and holds the secondaries slightly open causing either flooding or an excessive lean condition depending on where it gets stuck. When you test these carbs on the dyno install the factory thermistor choke unit on the intake and connect it to the primary choke linkage just like it would be in the car and you should have no issues with lean or rich readings. I've been rebuilding my own and super tuning thermostats for 30 years, they are the most tunable and reliable carbs

[@michaelbaumgardner2530]

George I hope your feeling better as the 340 comes to life.

[@sylvain-paulcote5470]

The ol' hammer handle trick to advance the timing!😂

[@NicksGarage]

Nick's official timing hammer.😄

[@leelavoie6753]

I appreciated that too…a flood of memories…

[@hacheyg]

I like that old fonze fix on the carb!

[@gulfy09]

Nick says here we go. Sure enough commercial comes on

[@OlSgtLove]

Hey Nick and George!!! George hope you are feeling better and happy !!! Appreciate all your hard work with Nick . Love seeing the 340 on the dyno ...The Themoquad brings back alot of memories of those 70s days and school ...Best Regards to All .

[@NicksGarage]

Thanks so much!!

[@DaleTerry]

I live in Vermont lake champlain. Just south of the border. I would like to take a trip up there to see Nicks shop! Love the show guys!

[@franker1111]

Great motors especially when there built right ✅️

[@SPEEDOFDOG]

Nice video. I had a similar problem years ago,carb was all over the place. Turned out the butterflies were hang up the carb gasket. 🤦‍♂️