boost vs cubes

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Aug 10, 2008 | 05:47 AM

#21

ayousef

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From: Dubai

Quote:

Originally Posted by crashly

ok... you win...

winning feels good

jk man

thanks for the explanation guys

now time for you to answer my other question, if you dont mind that is

https://ls1tech.com/forums/forced-induction/967940-open-exhaust-after-tt.html

Aug 10, 2008 | 09:03 AM

#22

71 chevy

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From: Dallas, Tejas

Quote:

Originally Posted by crashly

i think you missed the turbo class lessons...
boost is not power..
boost is a measurement of restriction in the intake manifold.

cfm or lb's /min is power...

a high flowing small cube, can produce more power than a low flowing larger cube engine... seen it heaps of times

our sbc tt , with twin 66mm turbos , made less boost but same power when i changed the cam from 258 @ .050 too 275 @ .050..
less restriction via large camshaft , allowed MORE flow threw the engine..
it actually dropped 9 psi....

race prepped small cube engine, with high flowing ports / cam / exhaust will crack all over a larger cube with std flowing heads / manifolds etc..

even tho the boost psi , is the same... one will flow more lb's of air per minute which equals more hp...

does this help you understand flow dynamics of an internal combustion engine.

what your saying is, a 76mm turbo @ 25 psi is flowing the same as a 66mm turbo @ 25 psi ???
same boost.... different flow of air...different power rating
cheers
ash

boost is the difference in pressure between the intake manifold and inlet air.
THEREFORE, boost is a function of NA hp. the engine size does not matter.

if you have a 350 making 500hp, given the same amount of boost, it will make more hp under boost than a 454 making 480hp

Aug 10, 2008 | 09:09 AM

#23

onfire

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From: Virginia

Ayousef, How did the PR compare with the 200ci vs 427ci in this link?

http://www.forcedinductions.com/help.htm

How did the efficiency compare?

Do the comparison, and you'll be enlightened.

Aug 10, 2008 | 10:53 AM

#24

94m6Z28

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From: Canada

so ultamitly, ither motor can make the power, one will jsut do it easier and a more efficent rate?

Aug 10, 2008 | 12:33 PM

#25

71 chevy

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From: Dallas, Tejas

Quote:

Originally Posted by 94m6Z28

so ultamitly, ither motor can make the power, one will jsut do it easier and a more efficent rate?

exactly

Aug 10, 2008 | 06:36 PM

#26

topend

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Quote:

Originally Posted by ninetres

I have issues with both of your responses. An equally built 427 with a turbo at 15psi, will make more power than a similar built 346 with the same turbo at 15psi. No question there. I think maybe you mistyped that sentence or something.

And the whole 427" vette vs the 200ci supra thing was more of a hypothetical question, so where you decided that the supra would make more power is beyond me. There are way too many factors to just state that.

if u take a turbocharged 346 " , increase its displacement by stroking/bore to 427" . You will not make anymore power. u only changed displacement yet the restriction stay the same.so if u want more power you`ll need a bigger turbo(less restriction).