Carb Adapter

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bucket

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So the AVS2 or 9895 would be a direct swap onto both the alloy oem spreadbore intake on my 70s 350 -AND- the high rise oem iron intake for my 85’s 4.3L V6? Asking because the Qjet I have needs to be rebuild and will not come apart. Could only get the lower plate off for a gasket replacement. Top 2/3 are stuck solid.

No, just an aftermarket intake with an open or split/open plenum design that is meant for use with a spread bore and square bore carburetor. Otherwise an adapter would be needed.

While that AVS2 has different sized bores, it essentially is still a square bore carburetor.
 

Scruffy49

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No, just an aftermarket intake with an open or split/open plenum design that is meant for use with a spread bore and square bore carburetor. Otherwise an adapter would be needed.

While that AVS2 has different sized bores, it essentially is still a square bore carburetor.
So rebuild the core I have or get an adaptor plate for a modern carb, or order a Chinesium repop… Got it.
 

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I’d honestly rather run a 500cfm Holley 2bbl on the 4.3 anyway.
 

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I’d honestly rather run a 500cfm Holley 2bbl on the 4.3 anyway.

I'd be inclined to do the same. You'll still need an adapter, but it's a combo that should work well.
 

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I have a spare edelbrock 2701 square bore dual plane intake . Would it be worth it to install this instead of my stock Quadrajet cast intake?

I would need to use an adapter like this, correct? It’s supposed to be reversible. https://a.co/d/8RabIbE

Engine is a high output 305 LE9. Stock quadrajet, stock, manifolds, dual exhaust. I would lose the air pump and EGR if I went to the 2701 intake. No emissions where I live.
 

Ricko1966

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I have a spare edelbrock 2701 square bore dual plane intake . Would it be worth it to install this instead of my stock Quadrajet cast intake?

I would need to use an adapter like this, correct? It’s supposed to be reversible. https://a.co/d/8RabIbE

Engine is a high output 305 LE9. Stock quadrajet, stock, manifolds, dual exhaust. I would lose the air pump and EGR if I went to the 2701 intake. No emissions where I live.
Leave your stock manifold and egr. EGR is not a bad thing,research it,thoroughly. It goes away when you are in the throttle,so no performance gain.Combustion chambers run hotter without EGR,Pumping losses increase when you remove EGR,you'll probably have to lose a couple of points of timing,possibly have preignition problems,mpg loss, and all for very little performance gain with the manifold at higher RPMs.
 
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AuroraGirl

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Leave your stock manifold and egr. EGR is not a bad thing,research it,thoroughly. It goes away when you are in the throttle,so no performance gain.Combustion chambers run hotter without EGR,Pumping losses increase when you remove EGR,you'll probably have to lose a couple of points of timing,possibly have preignition problems,mpg loss, and all for very little performance gain with the manifold at higher RPMs.
How much do you think having an ingested manifold helps or is it minimal
 

Ricko1966

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How much do you think having an ingested manifold helps or is it minimal
I've never injested a manifold. I'm guessing you are the reason for all the labels telling use not to injest cam lube,etc. ... As for my opinion I don't think having injested a manifold would help at all,it sounds painful and difficult.
 
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AuroraGirl

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I've never injested a manifold. I'm guessing you are the reason for all the labels telling use not to injest cam lube,etc. ... As for my opinion I don't think having invested a manifold would help atcall,it sounds painful and difficult.
INGESTED LOL! I meant, how do you think having a NON HEATED(blocked ports) manifold crossover would affect the combustion temps/timing amounts, separate EGR. Negligible?

Lol .autocorrect strikes.

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Way of the road
 

Ricko1966

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I don't think that blocking the hear risers cools the combustion chamber near as much as the egr does. I used to always block my heat risers when I was younger,looking for any horsepower I could gain anywhere. Can't say if it really made any difference or not never did a before and after. I did have carbureators ice up on me,at least twice that I can remember,it's a bizarre situation,you keep giving it more and more throttle but you keep slowing down. You look down the throat of the carb and it is restricted by ice formation in the throats. You wait until it melts and continue on. Now had zi not blocked my heat riser,would it have happened? IDK I also didn't run heated air cleaners. P.S. it's a completely different kind of heat blocked hear risers is ambient temperature of the intake charge, the EGR is not burning as much fuel and oxygen for a cooler burn.
Here's some EGR reading material.https://arnoldmotorsupply.com/buy-auto-parts-online
 
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AuroraGirl

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I don't think that blocking the hear risers cools the combustion chamber near as much as the egr does. I used to always block my heat risers when I was younger,looking for any horsepower I could gain anywhere. Can't say if it really made any difference or not never did a before and after. I did have carbureators ice up on me,at least twice that I can remember,it's a bizarre situation,you keep giving it more and more throttle but you keep slowing down. You look down the throat of the carb and it is restricted by ice formation in the throats. You wait until it melts and continue on. Now had zi not blocked my heat riser,would it have happened? IDK I also didn't run heated air cleaners. P.S. it's a completely different kind of heat blocked hear risers is ambient temperature of the intake charge, the EGR is not burning as much fuel and oxygen for a cooler burn.
oh I know that part, i was just wondering how much affect the heated manifold has on the same stuff. thanks
 

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