Can I run a 75mm TB on a stock plenum?

[astronut1885]

Which, if you read my post above, I will be, which is why I bought it. My blower has an integrated intake and plenum, all FRPP stuff. Eventually, I want some badass p+p'd heads and big blower cams. I think my purchase is justified.

 

[astronut1885]

View attachment 320432

That would be my blower.

 

[Winters98GT]

the reason I said it in the first place is because I have dynoed both the stock 65 and SVO, now FRPP, 70mm TB on my ported headswap car at CXI in 2001, and gained nadda.

Somebody on here claimed to me that they gained close to 1 MPH on a bolt on car with the TB/plenum. I have no experience with the plenum, so I cant say if its worth it or not.

Im not a believer in it, at all. I think the tb/plenum combo is just an increase in throttle response, and most people think they are gaining something. However, I do acknowledge that SOME, not all, of the TOP NA guys in the mid, low 12's with bolt ons do have an aftermarket TB/plenum on their cars.

 

[5spd GT]

the reason I said it in the first place is because I have dynoed both the stock 65 and SVO, now FRPP, 70mm TB on my ported headswap car at CXI in 2001, and gained nadda.

Somebody on here claimed to me that they gained close to 1 MPH on a bolt on car with the TB/plenum. I have no experience with the plenum, so I cant say if its worth it or not.

Im not a believer in it, at all. I think the tb/plenum combo is just an increase in throttle response, and most people think they are gaining something. However, I do acknowledge that SOME, not all, of the TOP NA guys in the mid, low 12's with bolt ons do have an aftermarket TB/plenum on their cars.

Good post.

 

[deftsound]

That's because you're analogy is laughable. straw to pvc is assuming the draw at the plenum (lets say even intake manifold) is trying to suck through but it cant cuz of the TB restriction. This just isn't so.
Factor in the limits of 165cfm intake ports, limits of stock intake manifold (and stock plenum if you're only talking TB improvement).
A comparable analogy would be sucking through a 2' straw, then lopping off the last 6 inches and changing it to the PVC. Well you're still suck through the staw - the big part at the end doesn't do much of anything.

Unless you have ported heads, a good intake manifold like a Bullit or P-51, good sized plenum (apart of those two intakes) then the TB size would matter, or if the case is you're blowing in air like in FI.

+1 if your going to spend the money on a 75mm tb you mine as well at-least get a 100$ professional products plenum...

 

[astronut1885]

Except my blower has an integral plenum as part of it (see above pic). I could have the best plenum in the world, and it'd still be in the parts box when I install the blower.