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Guest Message by DevFuse
 

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two intake manifold questions


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11 replies to this topic

#1 pyromanic

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Posted 11 July 2005 - 09:51 AM

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

#2 MilesFox

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Posted 11 July 2005 - 11:46 AM

intakes bolt on the same

swapping to spfi block will gain compression

#3 pyromanic

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Posted 11 July 2005 - 10:14 PM

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

#4 NorthWet

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Posted 11 July 2005 - 11:14 PM

... 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.

#5 MilesFox

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Posted 12 July 2005 - 02:08 AM

intake manifolds are exactly the same between at and mt. the only difference is carb intake is different then spfi intake, but between the same intake vs at and manual its the same part.

#6 pyromanic

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Posted 12 July 2005 - 08:18 AM

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.

#7 MorganM

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Posted 12 July 2005 - 08:29 AM

I say swap in the whole SPFI motor. EFI is superior :drunk:

#8 JWX

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Posted 12 July 2005 - 12:51 PM

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:

#9 NorthWet

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Posted 12 July 2005 - 01:00 PM

I say swap in the whole SPFI motor. EFI is superior :drunk:

Ditto.

#10 pyromanic

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Posted 12 July 2005 - 01:02 PM

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

#11 JWX

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Posted 12 July 2005 - 02:30 PM

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.

#12 ballitch

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Posted 12 July 2005 - 07:17 PM

no.......morgan had it right....EFI is better.............




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