I just acquired an 88 firebird. I have had a pontiac 350 sitting around for a few years. I have a pretty extensive background in swapping but what does it take to perform this swap. And please no answers about just putting a chevy in it. the car previously had a chevy 350 in it. Now its minus the motor. thanks for any help.

 

I'm currently putting a Pontiac 455 in my 85 Trans Am. I can tell you that you need the headers and mounts. You can get them from www.chiefmanyhorses.com . Pontiac 350's aren't really known for their performance, so don't expect to be killing everything on the street. You also need a BOP transmission, the Chevy one won't bolt up without an adapter plate. If I was going to go through all the work to swap a Pontiac engine into a thirdgen (which I am currently doing), unless it's a money issue, I'd go with a Poncho 400 or 455 rather than the 350.

 

Thanks for the info. I already have the tranny for the pontiac. Was there any huge problems you ran into?

 

Recently, HPP mag did an article on someone did an ati (IIRC) on a Poncho 350 & got like 600 or so hp.

 

What elese do you have to change in order to get the motor in there???

 

Put the correct mounts in and drop it in. Personally I put the frame mounts on the clamshells (the engine side mounts) then set the engine in, adjust it to the proper position, mark the position of the frame mounts, then take the motor out and weld the frame mounts in. I absolutely hate farting around with trying to put the nuts on the bolts inside the frame!!
Other than the mounts, it shouldn't be too difficult to get it in.

 

If he uses a BOP trans, can you still mount the torque arm?

And would you need a different crossmember?

 

Most likely have to use the B&M adapter kit for both the torque arm mount and crossmember mount. Just use a BOP TH350 (with the same length tailshaft). If you use a later model trans, say a 700R4, then you will have to look as I have never messed with them, I personally prefer the older TH350's due to their simple construction and known durability. One of these days I shall have to look into the overdrive trans, but I am an old school kind of guy and basically don't want any computers in my car, not even for a locking torque converter.

 

I dragged this out because i was interested in building a 455 poncho and shoving it in my trans am. nothing like "poncho inside" to have a whole new meaning. before i get flamed, I found this on a search, so don't tell me to do one. also, I checked (and subsequently put in my fav places) chiefmanyhorses.com. now: I was wondering about fitment. besides headers and mounts, what else needs to change? i was planning on going with a gear vendors overdrive unit behind a BOP th350. my chevy pattern th350 is a stout bastard, so I was gonna use it's internals (gears and stall and possibly shift kit) and stick new clutch packs in the BOP. can i still have A/C? or will this be 2-40 A/C? my brake booster? will it need to be moved or anything? or will it work? will it sag way down on my springs? I'm just exploring. I think this would be fun, and I plan on starting next year.... acquiring parts, cores, and going to work. (I'll need a DD by then, but I'll work it out later).

 

also, i have a spohn x-member and torquearm. if i need to use a th400, I can get the new x-member, or ask if my th350 member will work. my LS-1 sourced 10-bolt probably won't last worth a ****, but it's cool... I'll get a 9-inch or a 12-bolt when it frags. any thoughts from experience? anyone liked this swap? regret it?