Has anyone bored out their TB, installed with headers and good intake system and measured results? I was told boring it to 64mm can increase hp in the 4 to 6 range. I have a 94 GSR.

 

my friend installed a jg throttle body and skunk2 intake manifold and got 7-9 hp, but lost 2 hp of torque. this was on his n/a gsr with intake, exhaust, headers.

 

2 hp of torque. WOW thats a new one i always though that torque was measured in foot pounds..... just messing with ya man it happens to the best of us.

 

on an NA car it will hurt your driveability and will put any increase in power way up at the very top of your power curve, on a boosted car your power increase will come on quicker

the reason for the loss of torque is while the system may be flowing more air the velocity will be less

 

I cant quote you HP/FTlb increases .. but if you have a HIGHLY modified NA car .. IE: oversized pistons...cams .. complete airflow and fuel delivery overhaul... the throttle body would be the bottle neck at that point and be worthy of the bore

id recommend your fuel tuning be done after the TB bore

 

Also remember to port match the TB to the IM to get the best gains.

 

another side note ... buy a couple extra TB gaskets .. and give it to whoever is boring your TB ... they will cut the gasket to match ... just have him do a couple while hes at it .. incase you ever want to take the TB back off

EDIT: I have had awesome service from www.proflowdesign.com


[Modified by zilverz, 11:35 PM 12/18/2002]