B16, B18, B20
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By elrompetoto
#205782 Ok so I just found my 70mm blox racing tb that I had on my bosted single cam a wile back. if I put that tb on my bone stock ls will I gain any power ? Or is it just a waist of my time
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By elrompetoto
#205830 Yeah I figerd it will lean out but what if I get an after market fpr and pump up the psi a lil till it feels like its runing right ?
By Sabes
#205847 i believe juice said it would loose power because of loss of air velocity, not leaning out. It will kill the flow of air into your manifold because of less restriction. Now say you did some manifold work, a cold air intake, and a mild cam that would make use of the lesser restrictive air flow setup then you would make good gains. Lose low end though.
By Sabes
#205850 I couldn't remember what a b18b throttle body size was and upon checking i found it to be 60 mm. Stepping up to a 70 is a huge jump for a more than mild cam. Also your manifold would not be inadequate for a throttle body that size. You would have to upgrade to a higher flowing manifold and a good sized cam to make use of that throttle body. Or go back to turbo lol
By Sabes
#205852 to put it into prespective a 60mm throttle body has an area of 113.04 cm2.
A 70 mm throttle body has an area of 153.86 cm2.
That is a 36% difference in area.
Unfortunately i cannot calculate the flow rate difference at certain specs(vacuum, ambient air temperature,atmospheric pressure) but i can bet my left nut it will be much more than your engine needs as an n/a setup.
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By 92egdxhatch
#205903 I don't see any aftermarket throttle body doing any better than stock UNLESS the intake mani is port matched first.
By Sabes
#206042
92egdxhatch wrote:I don't see any aftermarket throttle body doing any better than stock UNLESS the intake mani is port matched first.


and that will see miniamal gains and probably more low end loss then high end gain. I say cam is a must if you are opening up anything after the air intake section.