make my 3.4 better

fierod · Post by **fierod** » Thu Jan 06, 2005 11:26 pm

I have a 3.4 with a 5spd Isuzu in my Fiero. Info on the motor:

Crane H272 cam
ported/polished heads, 5 angle valve job
exhaust manifolds replaced with sprint headers
Holley 390cmf carb
MSD 6AL ignition system w/coil
roller timing set, roller rockers
heads were shaved to increase compression to a bit under 10:1

The car runs great, but is there any more I can do to squeeze more power out of it? I want to suck as much power as I can out of this bastage

Shaun41178(2) · Post by **Shaun41178(2)** » Thu Jan 06, 2005 11:45 pm

you seem to have a pretty good start already

any flow numbers on the heads?

Any intake porting? You can still port the intake mani a bit to gasklet match or hog it out a bit.

There are adapters to fit a 500 cfm carb on it.l

You could try to add 1.6 rockers for a bit more lift if your springs can handle it.

Then there are things like power pulley, and a catback exhaust.

It seems your motor is built decently already. only a few more things you can do to it.

Any dyno numbers?
Any flow numbers on the heads?

There is always nitrous for cheap power. Somethign to think about.

fierod · Post by **fierod** » Fri Jan 07, 2005 11:14 am

actually, I've thought about the nitrous route but I'm kind of afraid of nitrous. I don't have any experience with it and don't want to kill my motor. I also have the tranny to think about. It's an Isuzu and I don't know if it can handle the big power increase that nitrous will make.

the intake was ported along with the heads, everything was port/gasket matched (intake, heads, exhaust). I have 1.52 rockers on it now and don't want to go with 1.6 because I don't know if the springs will be happy with it.

I don't have any flow numbers. I plan on taking it to the dyno sometime in the near future. I'm hoping for close to 200 rwhp.

the power pulley is a good idea, I didn't think of that. Right now it has a factory exhaust. Would a better system like the Borla be worth my while? Or maybe just a custom system with a free flow muffler?

thanks

Shaun41178(2) · Post by **Shaun41178(2)** » Fri Jan 07, 2005 8:36 pm

I woudl get a borla if you can or hell even a WCF 2.5 inch exhaust. That will prob flow better tehn a borla and might be cheaper. You should make some good top end power.

You can't really do too much more with that motor. Power pulley, and exh is all you haev left about.

Or hell even try to find a larger crossover pipe. I know someone made one. Not sure if its worth the money though as noone has dyno tested the stock one vs a aftermarket larger one that still bolts to the stock manifolds or the Sprints.

If you have the time and money step up to a more radical cam. Like a mech flat tappet with lots of duration. Yuou prob can't get too much more lift then what you have now without new springs but I have no idea what springs you are using now. A mech cam would add a bunch of power but would require bigger springs most likely and that would require more money.

For now you have pulley and cat-back unless you want to rip the engine apart. Thats about it.

Shaun

fierod · Post by **fierod** » Sat Jan 08, 2005 8:18 pm

thanks for the advice man,

I think I'm going to pursue a custom 2.5" exhaust with flowmaster muffler, then the power pulley of course, I'll put that on when I have an extra 10 minutes.

I'm going to see if a muffler shop would be cheaper than WCF on the 2.5" exhaust. I'll at least have to buy the flowmaster from WCF since they modify it to fit in the fiero.

I dont' think I'm ever going to be satisfied with this thing. Maybe a couple more cylinders would help.