So i have a jdm GSR and i bought a professional products WHIRLWIND® GSR Intake mani for it a while back and recently threw it on, now the motor has stock internals and I know that an aftermarked intake mani is not going to give any gains… but it is on the car and now it will not run correctly. It idles fine but whenever you rev it up and the tps passes 14 degrees it pretty much falls on its face, now the car is hooked up to chrome and every sensor seems to be responding correctly but it does seem to lean out, but even when setting it to get extra fuel it does the same thing, we cannot figure out wtf is wrong. Any ideas on how to resolve this? do i need to put the stock IM back on?
did you touch it? if so theres your problem 
Comon Nick i would expect that from Chad but not from you!
did you touch it? may want to check that. 
who am I to say anything. I’m on my way to a bakers dozen bottom ends ive been through
what throttle body does it suggest you run and what are you running?
They suggest their throttle bodies, I am currently just using the stock TB
Does the mani have a small NPT fitting for the coolant run reach the FITV and IACV? If it does not, and you deleted/bypassed the stock FITV and IACV you’ll need to change that in Crome, as well as increase the throttle tip-in values.
You can run the stock TB no problem with those, but they do recommend an ITR type TB that would not accommodate the FITV/IACV.
I had the same prob with mine. I have a usdm gsr with the same intake you have. I changed my throttle body and everything was fine after that. i put a 65mm edelbrock on mine.
sorry, just wanted to beat chad… hope u got it fixed…
problem solved 
especially if the other dude had similar issues and resolved it with a new throttle body.
Steve, i’m sure it ‘can’ run on an OEM throttle body… it just idles, but breaks up when you rev it :kekegay: