i have a 4.6 liter 2001 gt, i just recently installed a new throttle body and intake plenum along with spacers. the hp gain was decent but not quite what i expected.....anyways i talked to one of my gearhead friends and he swore that for 500 bucks i could have gotten a port and polish kit and probably gotten around another 40-50hp...........iS this true????? if so where can i find such a kit??? thanx a ton

 

Porting and polishing a stock intake and throtle body will only net you aprox 5 horsepower. Porting and polishing a set of stock heads when done professionally may gain you 25-30 horsepower and possibly as high as 40-50horsepower when combined with a good set of aftermaket cams. The cost of removal and porting and reinstalling along with the cost of gaskets and related misc hardware and fluids will far exceed the fiqure of 500 dollars that your friend came up with. A good set of cams start at aprox 595.00 and up alone not including any labor or related parts needed for replacement.

 

no way are you going to get that much gain on a TB and intake plenum

 

I have seen several shops advertise cylinder head porting for 500-700$, but without other mods you will never get 40-50 HP. That would take other mods, like an intake elbow, cams and long tubes.

 

MIKE IS CORRECT THAT YOU ALSO NEED A SET OF LONG TUBE HEADERS COMBINED WITH CAMS AND PORTED AND POLISHED HEADS TO GET NEAR THE 40-50 HORSPOWER GAIN YOUR LOOKING FOR. P.S. Mike I just sent you a e-mail

 

are there any kits available for this, or what all will i need to buy to do this......my friend is an aeronautical engineer so labor cost will not be an issue

if they do have these kits......i cannot find them
any names or web sites??

also i have another question......would a set of nice shorty headers work as well as the long with this app??

what will this do to my ecu??? :blob1:
THANX

 

There are no kits for this other than hand held grinders and flow bench equiptment and lots of time required to perform the porting. I wouldn't recommend your friend to attempt this on your car. You will also need to have the e.c.u. recalibrated wich is best done on a dyno with a exhaust gas anaylizer and have the air fuel ratios corrected.

 

short tube headers even if equal length will not perform as good as long tubes,but short tubes will be better than the stock exhaust manifolds

 

www.samotorsports.com .They sell kits to do headporting and even show you how to perform this operation.I would be VERY carefull about trying this yourself,you can do more harm than good in a very short time.There are several companies that use CNC machines to port heads,they are the most consistent,and they will be able to suggest cams that will augment the airflow characteristics of the heads.