I will be getting a set of new vortec heads from summit...the GMPP ones. I will also be getting roller rockers, and springs to accomadate a 480 lift cam easily...now i know u have to machine the valve guides or some crap like that to get the springs in...and should i have them ported or not??? what would be better? Also, what companies do Porting work in the Houston area???

 

What engine is this going on? Will it be a high rpm engine, or a more streetable low-mid rpm engine? For a street car I would go with either no or mild porting. If you're shooting for high revving power, then I would port them. Other factors affect this though, like intake, cam, etc.

 

It is for a 350 carb motor...street, everyday driver....but want about 340-350 to the wheels...what would be good? no porting? edelbrock intake and comp xtreme cam with 480lift...

 

For street driving, torque is key, not just horsepower. Porting the heads a little would be good, just mostly to even out casting imperfections. But no need to have tons of airflow through them, because the engine doesnt really need it. I would go with a dual plane intake, probably a performer rpm or equivalent. Choosing a cam is a little tricky, but something that works in the idle to around 5500 range would be good. HP is meaningless if you dont make your peak power until 6000 rpm. You'll be slow as hell off the line, and winding out gears all day long. I would focus on low to midrange torque for a street car.

 

I wouldn't port GM vortecs, they can't flow much more (+5cfm) nd you will most likely hurt flow(-25cfm)!

 

try them as is. you won't get 350 at the rear wheels
more like 370-400 at the crank.