4.6 Liter Horsepower

gt281 · 05-22-2003

Yes you can hog out and polish the upper intake and match the throttle body to the intake. Good for a few hp.

Quote:

Originally posted by Twokingsracer
Porting the 98 manifold???

DAVID119 · 07-03-2003

can the 98 heads be ported an polished to perform as well as the pi heads?

Twokingsracer · 07-03-2003

I doubt they could. I have read they can be ported to get around 25-30 more HP, but by the time you are done your pretty close to putting the money for a headswap up and gaining the full potential HP of PI heads. Might as well go the rest of the way.

David L Gary · 07-04-2003

There is a guy over on stangnet that runs a t-bird 4.6 that added PI cams and is running 14 flat. The PI cams do help our engines. Look at the overall air flows. Get thoses valves open faster and farther. IT will make more power. There are a lot of us that have not given up on the older heads. They make more power below 3500 by the way. With the right mods there may be greater average hp and tq.

BIGTONE · 07-04-2003

95 was the last year of the 5.0

1998GT · 07-05-2003

ported 96-98 heads outflow ported PI heads low in life, like below 3500 rpms, but above that the pi heads greatly outflow the older 4.6 heads.

quadcammer · 07-05-2003

Quote:

Originally posted by 1998GT
a trailblazer would get spanked by a 98 gt. With a stage 1 turbo kit seen in MM&FF you can run over 430hp and over 530 pounds of torque on pump gas. 8psi...

hahahahaha

a stock headed 96-98gt will put out no where near that with 8 psi. More like 330rwhp at most.

cramming air down heads that won't flow is pointless.

if u add newer heads then u have a lot of compression unless u eliminate the swirl dams or use svo heads.

pi cams are decent but there are much better options.

mike that intake porting stuff is bs and u know it.

1998GT · 07-06-2003

The stock heads of the 96-98GTs restrict our engines from makin serious hp but there are other ways around them. Our GTs can still be fast without replacing the stock heads but if you plan on making some serious hp then you will need to do a headswap, the ford racing performance heads or the PI heads will do good. That stage 1 turbo kit was for 99+ i'm assuming, my bad. But you can push way more than 330 rwhp using the stock heads.

in MM&FF it showed a gain of like 14hp with a ported intake AND a 70 mm throttle body, i'm assuming most of the gains came from that. You could prolly expect a few horses from doing that yourself.

Both the 96-98 and 99+ have dished pistons, its just that the dish in the 99+ is not as large as the dishes in the 96-98s, making the compression the same with the addition of the PI heads.

k6vox · 07-08-2003

The Mod motors can make some good HP and great TQ if you do your homework.It can be expensive, but what is nowadays. And yes with out puffers and Gas..

1998GT · 07-09-2003

Quote:

Originally posted by ZORLAC69
I just bought a 1998 GT, I've always owned Chevrolet's, because they're cheap to modify and build horsepower. What can be done
for Cheap Mods on the 4.6 Gt? I love my new car, but am very
suprised that it only has 215hp and under 300ft/lbs or torque, when
you can buy a TrailBlazer with a Straight 6 that puts out 275hp
and well over 300ft/lbs of torque.

There is a guy on here who has less than 260hp at the wheels but yet he runs 12s..