I just got a 1991 Firebird off E-bay and i have a monte Carlo SS 305HO and i did a .030 over bore on. the 91' Firebird has the 3.1L V-6 in it. how all will i need to get the 305 in the Firebird. i do not want the V-8 computer controled and i will be running a Holly 650CFM Carb. i know i need motor mounts but what about the bellhouseing on the Stock 700R-4 trans? will it bolt up or will i have to get a new bell houseing. Also does anyone new what rear end was put into the 91 Firebird with the 3.1L is it a 3.73 open diff? i need to get my parts list going so i can start saveing money. also what is the best shift kit out there? i heard bad things about the B&M shift kit. Let me know what you think! Thanks

 

Also the 305 motor came out od a 1986 Monte SS. and one more thing. What kinda of headers should i use? i want to run 4" pipes to the Flowmaster muffler with 3.5" pipes out. let me know what you think!!!

 

A 305 is a small engine. You don't need big headers. 1 1/2" to 1 5/8" primary tubes is all you're going to need. 3" maximum exhaust pipes.

I don't even have that big of exhaust pipes on my race car. 3" in and out on some bullet mufflers.

There's nothing special about that 305. Why not just drop in a good 350?

 

I Got the 305 For Free. and i have alread put alot of money into it. i'm thinking about just boreing it out again to a 350.

 

The rear end in that car is going to be something likle a 3.23, or a 2.73 one wheel wonder. As far as the motor, if your using a carb, you don't need to worry about the ECM. But you will probably have to use a new fuel pump. You might even think about new front springs. But like the other guy said- "why bother with a 305?" 350's are dime a dozen, and machine work isn't that expensive!

 

You can't take 305 cylinder walls to 4" to make a 350.

 

you can't? itsn't it the same block?

 

Nope. Externally they look the same, but if you ever open up the 305, the cylinder walls aren't thick enough to go 0.624" over. Some 305 blocks (late 70s early 80's) can't even go .060" over.

 

well do you know if the stock 700R-4 trans will bolt up to the 305? or do i need to get a new bell houseing?

 

If it's originally a 3.1, then you need a V8 TH700-R4

 

can i just swap out the bell houseing on it?

 

No. It's a fixed case.