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two intake manifold questions


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Hi,

#1

Is there any difference in the carbed intake manifolds between, say, '86 EA82 auto trans and manual?

 

The reason I ask is that I have done the tranny swap to manual. Should I be looking for an intake from a manual trans engine?

 

#2

If I swap to an EFI block, and keep the webber, how much HP might be gained?

 

Thanks,

Pyro

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intakes bolt on the same

 

swapping to spfi block will gain compression

 

 

Thanks for the reply Miles. Yes, intakes bolt on the same, but does the intake for a man trans flow any better than the intake for a auto trans? I'm doubting it, and thinking that they are identical, but dumb question or not, had to ask.

 

Ok, yes, I had heard that the spfi block will gain compression. So higher compression means some more ponys correct? Just wondering how many, if anybody knows.

 

Thanks again

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... Ok, yes, I had heard that the spfi block will gain compression. So higher compression means some more ponys correct? Just wondering how many, if anybody knows...

I believe that the difference between carb and SPFI pistons is 9.0:1 vs 9.5:1. Thermal efficiency increase approx 10% for every "point" (1.0) of increase in CR in this range. So you are looking at about a 5% increase in power. Not worth chasing after, but worth it if it drops in your lap.

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Thanks Miles and Northwet.

 

I really figured the intakes were the same. But I know how much I don't know. Now I know.

 

So, maybe aprox 5% eh. Mmmm. Ok, 5% of what? I mean, now I'm wondering what the Horsepower of a weberised EA82. (assuming proper tuning, which is dubious in my case)

 

5% doesn't sound bad. And that SPFI motor is just sitting there in the other donor.

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or use the SPFI manifold with the webber, thats worth some ponys as the FI manifold flows better. or for the bestest one evAr use MPFI heads with a custom manifold and dual webbers. :lol:

 

Huh? Well it never occured to me that I could stick a carb on the SPFI manfold. I just assumed (duh, not to smat huh?) that the throttle body would be a differnt bolt pattern and such. Or would I need a custom adapter? Shxt, I'm gonna go look at this right now.

 

Flows better why? Ill go look.

 

Thanks, Pyro

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flows better cause it is bigger at the neck (where the carb/throttle body bolts on at) same size runners and single port tho. and yes you would need to make a custom adapter. there was a guy who did it might have been on the old board.

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