I was wondering if it would hurt your performance if you go too big with an aftermarket throttle body? I have a 1.8 now but plan on 2.0 in the future and dont want to buy 2 TBs if I dont have to but dont want to loose horse power either
TIA

 

You can go to big.Not so much power wise but drivablity suffers.I don't see the need for anything bigger than the stock gsr one on something street driven.There are turboed engines making close to 600hp with a gsr tb.
Glenn

 

uhhh...........i dunno if u noticed but we are in the all motor section here, not the FI section.

 

Yes, you can go too big. If you get a larger throttle body you need to make sure the Intake manifold it port matched to that TB.

 

Just an example that the tb isn't a big restriction in air flow.I thought about the turbo reference and was hoping no one called me out on it.
Glenn

 

does the same thing apply with intakes as well ? i dont know the exact specs of my throttle body, but say if it was 2.75", would a 3" intake be too big ?

 

The intake tube size (between the air filter and tb) isn't as sensitive to diameter as the td is.The length and shape has tuning benefits but won't cause drivablity issues like a huge tb will.
Glenn

 

I'm running a STR 68mm TB on a B18C5, makes 4-5 hp at the wheels. I wouldn't go anything larger than that though. If its too large, you can get idle problems.

 

im useing STR 70mm here

 

just picked up a STR 70mm so we shall see what happens.
even if it doesnt help it is SUPER BLING!