Gains on intake porting?

[Jetson8294]

The title asks the question. Does anyone know the approximate HP gain/FT-LB loss this makes/gains. Thanks!

[mwinkle353]

I didn't have mine dyno tested. But my Butt-o-meter tells me that the top end gained quite a bit over stock. But at the same time, I felt that I lost a bit down low in the rpms as well.

My guess, on your setup, would be about 15hp.

I'm sure brent made more in the upper rpms, due to his exhaust setup.


Just a guess,

Wink

[Jetson8294]

My car doesnt have mutch but... 52MM, Cone filter, and a 2" straight pipe. And yea it runs like a bat out of hell now.

[92lebaronGTC]

I'm in the process of porting the hell out of an upper plenum I bought at the junkyard, is it necessary to gut any metal out of the bottom half or is most the power increase found with the top portion.

Should I remove the middle rudder too?

[Ondonti]

ported plenum is great. Low end power is lost. I dont mind as I dont pull trees.

I often lug the car around at 600 rpms in 2nd through 4th gear all the time instead of changing gears. i still do pretty good.


Ported plenum wakes up the top end. I have a stock plenum and 52mm back on my spirit recently while the good stuff is on my duster.
It is very noticable that the top end of the powerband near the rev limiter is basically useless.