Hey guys... I'm now an owner of a 1985 Pontiac Firebird... I bought it last night. I'm formerly a fourth-gen owner, I had a 93 Camaro Z28 that I got in a bad accident with back in June...

I bought an already modded 85 Firebird with a 355 and a T5.

Mod list:
Ported Iron heads
Comp Cams cam (in the process of getting specs)
1.6 roller rockers
Edelbrock Performer RPM intake
750 CFM carb
Flowmaster, no cat.
New everything else (brakes, alternator,starter, fuel pump, etc)

Runs great, the motor was built by a very reputable local shop to be over 300 HP. The whole setup has 3,000 miles on it..

The only thing I'm looking for right now is a set of long tube headers to really make this complete and a good posi since it's dog-legged.

Anyone know if a fourth-gen torsen take-off posi will work in this year of Firebird?

Also, I need to know what headers are better than others.. Fabrication of exhaust is no problem. I don't want to spend a lot, but I do like the Hooker LTs if they're like the fourth-gen ones.

Thanks a ton...

 

the 4th gen take of posi wont work on your 85. 1989 and up is when they went to 28 spline axles. Only if you swap the axles can you use a take off.

Hooker long tubes will fit of your doing a cusom exhaust. Hooker has a shorty set that will use the stock y-pipe and a 3 inch cat back would be sufficent for that much H/p.

 

I will have to search the local salvage yards for a set of 28 spline axles then (and hopefully find a good posi while I'm there )...

If I have dual electric fans installed (aftermarket fans) can I get rid of the hand cutter...errr flex fan that I have on there now? It's got both electric and a flex fan driven off the water pump.

Anyhow... does anyone have information on what it takes to make the stock V6 gauges work on the V8? The car has a nice looking "normal" gauge cluster, except only the speedometer, voltmeter and fuel gauge work correctly. The rest of the gauges (coolant, oil pressure, tach) are all externally mounted and I like a cleaner look.

I've had thoughts about swapping in a fourth-gen firebird cluster and making it fit & work, but I don't know if anyone has done that before....

Thanks...

 

If it was a V6 car, all the guages should be right w/ the exception of the tach. I'm sure somewhere out there - someone recalibrates them. But, it is much easy to get a V8 cluster from a bone yard.

What color is this car? I used to know of a silver one like that in the Daytona area.

On the Hooker LT's, I have them on my car. The fitment is pretty damn good. Had to go to a mini starter and a do a little trimming on the frame. The fans should be fine, I ditched my stock single electric fan and run twin BeCool fans. Previously, the stock single fan was more than adequate for the old L98.

 

Hooker longtubes are great for these cars. If you're monetarily challenged, Hedman makes them also, for less money.

Drop the flex fan, it's just sucking up horsepower. The dual electrics will cool her just fine.

Be careful with that T-5, they don't have the best reputation for holding up to 300 horse. Don't do any clutch drops and you should be alright.

If you need to change gauges just get factory V8 ones for the car. They'll bolt right in and might already have wiring present (depending on who dropped the 355 in it.)

Enjoy!!!