notice the sig..i have ported heads and 1.6 SA roller rockers..was wondering if porting my intake manifold would help amke some extra juice on the stock cam along with throwing on an electric csi waterpump..the car with a crappy A/F and a vacuum leak put down 298 rear wheelhp, 309 rwtq..so im fixing it (vacuum leak was an egr hookup on the back of the intake manifold)..so i fixed that with a soda can haha and im isntalling a new tune..few questions..how much will the car pick up with the ported intake on the mods in sig..it didn't seem like there was much room to hog out on the stocker but i want to do it anyways..lets me know

 

Pretty sure it won't do anything unless you get a 58mm throttle body, in which case you MUST port the intake only because the stock intake is good for up to a 52mm throttle body. Stock is 48mm. This is all based on what I have read.

 

id leave it alone. all you will do is kill velocity.

 

Having a professional do it might be worth 10hp at the high end of the rpms. Your potential is much less then that, and your error potential is much higher. I'd leave it alone unless your just opening the bores for a 58mm tb