How to Choose the Correct Spacer

[@DanielSmith-yp7mw]

I currently have a Moroso phenolic spacer on my BBF, stock manifold. It's only like maybe 3/4" but it works really good. The base of the carb will actually be cold after running around. Not just unheated, but actually cold. No manifold heating at all. It'll warm up with just ambient engine heat after shutting it down, but not get hot at all from the manifold. Nice info btw.

[@MuscleCarSolutions]

Sounds like you’ve found the right solution!

[@johnweaver8470]

The heat soak issue is a real pain, come out of the store and and have to crank it over and clear out your flooded engine, now I know what to do keep the videos coming

[@MuscleCarSolutions]

Yeah it’s always a pain. Heat blocking spacers are the best solution as of right now. Maybe down the road someone will think of a better way to isolate that heat from the carburetor. Would love to see a plastic injection molded intake to see how it does. Rather expensive to make one though! Thanks as always for stopping by John. Always appreciate it.

[@DisDik1984]

​@MuscleCarSolutions Also, if this doesn't work, you can add the "anti vapor lock" style fuel filter. Just a thought: it can be a pain to route an additional line, but it may be worth it if that's the case.

[@MuscleCarSolutions]

@@DisDik1984 a return line is never a bad idea, but a majority of that heat soak comes from the 220 degree source directly under the carburetor! I’d agree though. Both together is the best possible solution.

[@caspar0777]

I've got the same problem. I know there is a sort of fuel filter with a "bypass" to the return line, in case of to much pressure when hot... I ordered one and will fit it one of these days...

[@CarsonL2000]

@@caspar0777 do you also have a carb spacer on it?

[@OsoBlanco17]

Hey MCS, just wanted to say thank you. From the wealth of knowledge I’ve gained from your channel, to your responses to questions I’ve had…you have pretty much fixed my car. Thanks to you I choose the proper carb, (with spacer!) and finally got rid of the dreaded ping after you mentioned my issue sounded like the timing was too advanced. Now my engine is cranking out all the power I expected and my 87 Firechicken flies again!

[@MuscleCarSolutions]

Nice! 😆 I’m glad you were able to work though it! 🇺🇸🏁

[@BPattB]

I just love the fact you has the Edelbrock 289 Preformer in your video. With my AVS2 I did have issues with the cheep 4 hole spacer. I had to open the secondary holes a bit with a Dremmil

[@MuscleCarSolutions]

I’ve got a few ford intakes here. Hadn’t used one in a video for awhile. 😏

[@isaelmonsivaisandrade1425]

I AM FROM MEXICO, LAST WEEK I BOUGHT A CAR 1980 WIT ENGINE 307 CHEVROLET 5.0 AND I SAW A FAIL IN LOW RPM I HAD 4 CILINDERS NOT WORKING, BUT IN HIGHT SPEED I HAVE ALL GOOD. I SEARCHED THE FAIL AND I FIX THAT. MY SPACER WAS THE PROBLEM I HAD A SPACER WITHOUT SEPARATION OR NO SEPARATION AND I HAD CARBURATOR EDELBROCK 1405 WITH DUAL ADMISION. I AM VERY HAPPY NOW.

[@marcoceccarelli6415]

In my experience dual plain intake manifold. Work best with a open spacer. Four hole Spacers work good for single plain.

[@Foxcanfixit]

Tons of good information. Shop I worked at did mostly Q-jet stuff and a 1/2-1” phenolic resin spacer was our go to when fighting heat soak

[@MuscleCarSolutions]

Heat soak is a nightmare!

[@fruitful7753]

Good explanation of the various spacer-heat plates to different manifolds.

[@VinoRatRodbuilds]

I like learning new car stuff and I always find it here on the muscle car solution. 👍

[@MuscleCarSolutions]

That’s what makes your channel informative as well! Lots of creativity! Love it.

[@DesertRatFabrication]

Great video Brian, good stuff to know especially crushing in Eastern Washington in the summer, hope everything is well😀😀

[@MuscleCarSolutions]

All is well here! Hope you’re enjoying the nicer weather in the PNW.

[@DesertRatFabrication]

@@MuscleCarSolutions 👍👍

[@ItzTheDay]

I have a 72 El Camino SS 396/402. RPM Air Gap intake manifold with a Performer 14073 750cfm carb. I ordered a 1" Edelbrock 8720 open wood spacer. I hope I ordered the right one. Most reviews of the plastic type were bad due to them warping and causing vacuum leaks.

[@MuscleCarSolutions]

They generally don’t warp. They have open exposed cells on the bottom that will leak if not sealed up with the plate adapter. It’s not the fault of the material. It’s the user installing incorrectly.

[@ItzTheDay]

@@MuscleCarSolutions My main concern is the open spacer going on a split intake.

[@MuscleCarSolutions]

@@ItzTheDay if it’s the 1”, I have run that many many times and never had issues. Confirmed on many engines built and dynoed with both. If it’s still a concern, then just run the divided spacer.

[@ItzTheDay]

@@MuscleCarSolutions I only found Edelbrock 1" spacers made in open, divided is in 1/2 and I also believe in 3/4? Is it possible to stack two 1/2 spacers?

[@MrTheHillfolk]

@@ItzTheDay Not a problem stacking them, I've seen that before. Maybe if you're picky just see if they mate together nicely,and if see if the joint needs a little cleanup on the ports to smooth em out

[@richardnixon9324]

Insanely good info this man gives

[@KingNothing2x4]

400 mopar with edelbrock rpm intake with 1407 edelbrock 750 and 1" edelbrock wood spacer....Works perfect

[@davestewart-k9t]

Running a weird 8020 stealth on a 302 ford, tried open and 4 hole phenolic spacers, 4 hole worked noticibly better on that app!

[@RonaldLewis-py6yt]

Covered a lot of good information 👌 thanks for sharing!!

[@DavidSomers-i5h]

Great content, do you need a gasket from the manifold to the spacer and from the spacer to the carburetor? Do you need a sealant,?

[@landoncustomclassics]

Great video! This always makes me think!

[@RobertLiebentritt]

I enjoy your videos. I'm hoping you can help me on a Carb choice. I have watched your video and many others and just seem to get more confused. I have done the math and come up at 570 with VE and 660cfm without. I used the holley carb selection tool and get 750. I'm replacing a holley 3310 750 cfm. I have a 70 Mach I with a 351 (highly modified) cleveland and a 2800 stall FMX. The guy I bought it from was a street racer. I'm going to give you what I know about the engine. The block has a 10/10 crank, factory flat top pistons, 5.90 lift by 284 degree clay smith solid lifter cam @108 degree lobe ctrs. 351m 2v heads with reshaped chambers ported and polished with roller rockers with polylocks. Edelbrock 2v intake ported to match heads. I plan to change to a 4r70w auto overdrive controlled by a Quick 4 controller. The car will be used as a street driver. Won't ever be raced or anything like that. I want it to run good, dependable and still be fun to drive. Won't see max rpm. What would you suggest. I called holley support and told them what I had and they recommended a 670cfm Street Avenger. I'm not familiar with Edelbrock's except what I have learned from your video's I have no brand loyalty. Thanks for what you do and hope to get your opinion. Robert

[@MuscleCarSolutions]

If you’re just going to cruise it, then you’ll be just fine with the 650 CFM size. It will have good throttle response and will be easy to tune (doesn’t matter what brand you go with). If you decide you do want to drive it aggressively, I’d likely go with a larger size. Really at this point it all depends on how you want to drive it.

[@RobertLiebentritt]

@@MuscleCarSolutions Thank you for your response.

[@deerslayer5863]

A tapperd 4 hole spacer is the ticket for open plenum intake

[@MuscleCarSolutions]

In theory it might be.

[@terrystein1552]

Would you run a gasket under the spacer and under the carb? Great and informative videos!

[@MuscleCarSolutions]

You have to, yes.

[@RecklessEnterainment]

From seeing dyno results typically an open spacer on a dual plane intake will actually gain a decent amount of power because it affects the distribution a little. Doesn’t really have the same affect on a open plenum or a single plane intake though. I think in reality there is no power loss to be had running either style spacer but it probably affects drivability more than anything.

[@MuscleCarSolutions]

Don’t think either is anything anyone would notice. Given most folks don’t tune their carburetor, I’d say that’s a bigger source of positive change.

[@RecklessEnterainment]

@@MuscleCarSolutions I noticed the throttle response wasn’t quite as good on my 360 with an RPM airgap when I put the 1” open spacer on it. But yes I’m surprised how many people throw a carb on out of the box and never dial them in.

[@MuscleCarSolutions]

@@RecklessEnterainment and then either just accept it and pretend it’s ok, or blame the carburetor as “junk”. It’s a wild world we live in!

[@RecklessEnterainment]

@@MuscleCarSolutions most carbs you see for sale are listed because they didn’t run right on the car because no one ever adjusted it lol pretty crazy.

[@MuscleCarSolutions]

@@RecklessEnterainment yup. I’ve made a nice living buying them and reselling. 😆

[@paulpruitt2776]

You could use a sheet metal heat shield under the carb or a spacer and change to the old foam eldabrock air cleaner and get more clearance

[@MuscleCarSolutions]

Used to have those back in the mid 80s. I still have one. If I find it I’ll post pictures on my IG. It didn’t work very well.

[@daviddesilets6108]

I have a Chevy 454 Engine with an Edelbrock Performer 2 manifold. I have an Edelbrock AVS2 650 Carb to go on it. Basically a heavy long haul highway pick up needing a lot of torque.and I am concerned with heat build up in the carb. I picked up an aluminum Edelbrock 2696 Carb Adapter KIT, a Edelbrock Carburetor Spacer 8723; Square Bore .500 4-Hole Wood Fiber, and an Edelbrock Carburetor Adapter Plate 2732; then a Square Bore to Spread Bore Steel .093 thick plate. My thinking of the stack up was to put the 2793 plate on the manifold to stop any vacuum leaks and then the 2696 4 hole Carb Adapter on it, but the output expansion bore holes of the 2696 block are too large for the opening of the .093 thick plate. Do I dremel out the .093 plate or is there another place in the stack for it, or don't use it. Yes, I realize that most of this is for a cast iron GM manifold. I'm just trying to keep the carb cool and the torque up. Your thoughts on this would be greatly appreciated.

[@MuscleCarSolutions]

@@daviddesilets6108 goodness….there’s a lot going on here! The 2696 is an adapter. Not needed for that intake. Not sure what a performer 2 intake is. Is it the performer with the spreadbore and square bore pattern? You can use the 2732 to ensure the intake is sealed. If you’ve got room under hood, then run a 2” spacer like the 8712. You won’t lose or gain any torque from it being an open center.

[@daviddesilets6108]

@@MuscleCarSolutions The Edelbrock Performer 2 intake that I have is the 2161. It is a dual plane with with approx. 1.5" openings up front and 2 .25 openings in the rear for the throttle plates. Sort of a Rochester adaptation in a dual plane with the split down the middle. I can't seem to load a picture of it to show you. This is why I was thinking of using the 2696 Adapter due to the AVS2 with the larger rear throttle plates, and the adapter directing the air-fuel to the 4 corners of the manifold. Placing the wooden spacer on top of the adapter to keep the carb cool seemed to be ok depending on the rear throttle borr openings that may have to be opened up for clearance. The snag that I hit was the 0.093 plate at the bottom will not fit the adapter plate. So, do I really need it. Will the adapter seal up to the manifolt to prevent the dreaded vacuum leaks?

[@daviddesilets6108]

I just looked up the Edelbrock 2101 intake manifold that you show in the video, and compared it to the 2161 that I have. The carburetor mounting surfaces looked nearly the same and is what I was trying to explain to you above. If I put the plate on the manifold the open center is not wide enough to accomodate the openings on the bottom side of the 2696 adapter plate.

[@MuscleCarSolutions]

@@daviddesilets6108 I don’t know how to get this to sink in. You don’t use a 2696 carb adapter on a dual pattern Edelbrock intake. That’s not its purpose.

[@prycewilkins]

Ok so i have a Edelbrock airgap square bore intake and an AVS2 650 carb, which heat reducer should I run? Or which one would you suggest. Im new to the carburetor world so any help is greatly appreciated.

[@kriswalker1898]

I have a 73' monte carlo. If I use an edelbrock performer intake with quadrajet carb, which type of spacer would be best? Thanks

[@DimZin]

I have a marine Edelbrock 4 barrel that has rust on many parts. What would be the best option to remove the rust and also make them rust proof? Is high heat resistance paint a good choice?

[@MuscleCarSolutions]

What part number carb?

[@DimZin]

@@MuscleCarSolutions The number on top is 8867. There's no edelbrock written anywhere but there's a W on one side which i believe stands for Weber. I think it's a weber edelbrock 1400. It's on a Mercruiser v8 5.7L.

[@MuscleCarSolutions]

@@DimZin that’s not a marine carburetor.

[@DimZin]

@@MuscleCarSolutions It has all the features you mention on the video about marine and street carb differences. It actually looks exactly like the one you show in that video.

[@DimZin]

@@MuscleCarSolutions I can send you some pictures if you want. You might be able to identify the model since you know more from me

[@purebredamericanmutt]

I got the Holley carb with the JB weld on it. Found out that the 327 is over bored so I just got a 1981 Corvette motor. 207 block and I'm going with 355 Scat rods and crank and Wiseco pistons and Comp cam roller not sure of grind yet but plan on a hundred shot of NOS. My question is not plates but I seem to remember that there was a formula to size an air filter for the size of motor?

[@MuscleCarSolutions]

Yup. There is but I generally don’t consider it. At least in most applications. A good sized filter is generally all I’ll look for. If someone what’s to run some tiny, less than 10” element, that’s when I generally make a suggestion.

[@purebredamericanmutt]

@@MuscleCarSolutions I have plenty of room with a 2in cowl hood on a 84 El Camino so I'm thinking 14x3 and that's with the plate on it. I could go 14x4 and still have around an inch from the hood

[@flinch622]

I chose a 4 hole over an open spacer when I don't really want to increase plenum volume - it behaves more like a venturi extension. Most cases, that's a street application.

[@MuscleCarSolutions]

Unfortunately there’s no good way to test that theory without a flow bench. But I’m working on that……😏

[@briang4470]

It really seems like the fuel formulations nowadays boil/vapor lock extremely easy. I understand that heat soak and vapor lock has always been an issue but in the past few years myself and others i know that have had proven setups that worked perfectly fine for many years with no changes that now vapor lock everytime they get driven. Its getting ridiculous it seems like now mechanical fuel pumps almost aren't viable anymore because the fuel just boils in the pump and drop base air cleaners seem to really cause trouble as well. Also no matter what fuel system used(mechanical pump/electric pump,carb or injected), a fuel return line is basically mandatory nowadays. Also alot of the aftermarket throttle body injection setups also sometimes need a phenolic spacer as well as they have also been known to have vapor lock issues just like carbs, especially in dead head systems. Even some late model fuel injected cars nowadays occasionally have vapor lock issues, its must be related to the fuel used these days.

[@MuscleCarSolutions]

It’s going to get much worse if lawmakers can get E15 mandated as the standard. E10 has been a nightmare. Carburetor folks suffer the worst. Terrible stuff.

[@hankhill4406]

I need some info here. I have a weiand dual plane intake and a 1405 preformer edelbrock carburetor. I got the edelbrock 9266 heat insulator gasket and the 8722 1/2in spacer kit. I would like to combine both. Can i use the insulator gasket as the mounting gasket for the spacer? Does there need to be a paper gasket between the intake and insulator/ insulator and spacer? Do the gaskets go on dry or do i need sealer?

[@Tablesaw818]

Yes. Insulators don’t require a gasket. I rub my gaskets with grease. Makes it easy to reuse them in the future.

[@caspar0777]

thanks for this nice explications. On my 455 trans am I've a trottle problem when the engine is hot, but I don't have much room between the scoop and hood. After a little rechurch on internet I found a company, Jomar Performance, who sells a 1/4" Phenolic 4-hole carb spacer(model 5050) for my Rochester spreadbore. I can't put thicker as 1/4"..., so placed an order and I'll try it soon. I don't know this company from Pontiac MI, hope it's serious stuff. We'll see. Cheers from France

[@MuscleCarSolutions]

@@caspar0777 have to do the best you can when you have limited under hood clearance. Best of luck!

[@RobertJones-pj4sv]

What is your opinion on an autolite 4100 I have one and honestly I like it but I would like to learn more about it I'm sure u have messed with one was looking at pros and cons

[@MuscleCarSolutions]

It’s actually a decent carburetor but you’re gonna work for it. Parts are a bit harder to find or acquire. Jets are a little easier and power valves no problem. I know there are more folks that have messed with these a lot and seem to like it. It’s more of a stubbornness that will keep you looking for spare boosters and learning how to tune them. I guess that’s the pros and cons. I have tuned a few and thankfully they had some spare parts to make it a little easier. I’d 100% suggest tuning with an AFR. It will help you go down the right path with changes. Ignition timing is critical as it is with any carburetor tuning.

[@fuelbasti]

Edelbrock recommends the dual spacer for my performer manifold but it does not fit very well because the curved shape of the manifold. However, most important thing is to have a return line and a spacer is just cosmetic in my opinion. Great video again.

[@jkhippie5929]

Does the height of the laminated spacer make a difference to cooling ? Can I get a 2mm laminated spacer and do just fine ?

[@MuscleCarSolutions]

@@jkhippie5929 you want as thick a spacer you can run. 2mm is nothing.

[@Skoog.]

Isent the Air-gap intake made to do what the open spacer does on the left intake at 04:30 ??

[@tooljunkie6003]

Another detailed video , thanks again

[@tooljunkie6003]

Could you use a wood and rubber style spacer together, to increase thickness? As I only see 0.5 inch spacers Should you use the gasket when using the wood spacer?

[@MuscleCarSolutions]

Yeah you can mix them if you want. There are several different sizes. I linked a few in the description. It’s really an under hood space issue. The 1/2” stuff is very popular as that seems to be the one folks are most comfortable in fitting under hood of cars. The taller they go, the less options there are. Yes on the gaskets. Both sides.

[@tooljunkie6003]

Thanks again , I need to add the gasket then. As I was told the gaskets were optional 😮

[@MuscleCarSolutions]

@@tooljunkie6003 ack! Yeah for sure not optional. The 1/4” spacer can be used without a gasket in most instances, but even those I’ve seen leak. Wood or phenolic plastic for sure run gaskets on both sides. That will seal them up!

[@kevinhudson3153]

What you have said about the heat insulation spacer kinda scared me on my project

[@MuscleCarSolutions]

@@kevinhudson3153 scared?

[@kevinhudson3153]

@@MuscleCarSolutions there's only a 1/4 inch gap

[@MuscleCarSolutions]

@@kevinhudson3153 alrighty. 1/4” gap where? If you’ve got a question I need some details of what you’re looking for or why this is a scary situation?

[@kevinhudson3153]

@@MuscleCarSolutions the divider in the intake plenum,I cut the center out of the insulated gasket with a Dremel tool to get the pattern of the quad to a square bore

[@f150bft]

I have a 5.0 Mustang ll with very little under hood room. Performer intake and the Summit carb (4100 style) Any spacer much more that 3/8 of an inch won't work for me. I have heat soak issues so what would your thoughts be for my situation?

[@MuscleCarSolutions]

Can only do what you can if you’re not willing to make some drastic changes.

[@f150bft]

@@MuscleCarSolutions I have bought another hood to cut and try...so maybe that's where I go.

[@MuscleCarSolutions]

@@f150bft drastic situations generally drastic solutions. Hope it works!

[@PACBrian]

oops im using the wrong one on my performer lol thnx man

[@MuscleCarSolutions]

😆 easy fix!

[@brenden0820]

Will a spacer make an engine more lean?

[@MuscleCarSolutions]

@@brenden0820 it can but you won’t see a drastic change in the data.

[@brenden0820]

@@MuscleCarSolutions I see. Well then the issue I must be experiencing is bad tuning. I feel like I’ve tried just about everything to remedy the issue but can’t get it dialed. I have an AVS2 carb on a dual plane intake on a sbc 350. I don’t have a crazy set up. The cam is better than stock but nothing that would be considered race application. I’ve went to larger jets, added a spacer gone up and down on step up springs with all seemingly having no affect. It’s strange to me because I had an older Edelbrock on it and it ran amazing until the accelerator pump went out. Any recommendations also sorry for the novel

[@MuscleCarSolutions]

@@brenden0820 I’m gonna have more questions right now than answers. So if you’ll indulge me….what do you feel is the issue? Not enough fuel? Hesitation/stumble/bog? What size carburetor are you running? You made a random jet change or you followed the tuning chart? What is your initial timing set at and when does your full timing come in and what is it? Are you running a pressure regulator and what do you have it set to? If you don’t know the cam specs, can you at least tell me what your max rpm is or how you’re driving? Cruiser/occasional racing/etc? All these details will blow me know where you’re at now and what I can suggest you can try next. Just need the full picture.

[@brenden0820]

@@MuscleCarSolutions I believe it isn’t enough fuel. And I guess for a lack of better terms “it has no get up” like it putters even at 60mph. It’s a 650cfm avs2 edelbrock. I went back to the stock jet and metering rod because the person who had the carb before me put small one in it. The timing is set to 12 degrees. There has been no mod to mechanical timing. I’m running a regulator and it’s set to 5. I have a cam card but I’m at work I can get you that info around 5. And it’s a daily but id like to have a little fun with it

[@brenden0820]

@@MuscleCarSolutions the can is comp cam part # 12-210-2.

[@sawyerbarnes7439]

Trick question. Nitrous spacer is the best haha

[@MuscleCarSolutions]

It’s extremely difficult to argue with that kind of logic!

[@deerslayer5863]

Open spacer on daul plain kills the carb signal

[@MuscleCarSolutions]

You’d assume so, but I can tune on either one and then swap to either one and the tune doesn’t change. It’s more important to match up the dual plane with the correct spacer. In an open plenum, it’s not that critical.

[@Aaron-hd8ql]

You forgot to mention a gm spreadbore intake Manifold now I don't know which adapter to buy.

[@MuscleCarSolutions]

@@Aaron-hd8ql didn’t really forget. They weren’t relevant to this video. There are a few options out there but almost all of them are four hole spacers. Just choose the one that will keep everything under hood. 👍