PLEASE HELP, I have a 79 Trams Am with a 455. I ran across an 90 firebird in perfect shape but with no motor. I'm looking to save as much money as possible. So I was thinking of putting the big block in the place of the 302. How much trouble would this be as far as transmission bolt up,room under the hood ect, Also what kind of money would it take?  

Wow, I don't know where to start with this one! Nothing will bolt up, the true Pontiac V8 never came in these cars, so everything will have to be custom. The trans will require an adapter or replacement, the mounts will be different, the car is setup for EFI, the 455 is carbureted. Sure it will fit, but it will be a ton of work and won't pass any kind of smog check anywhere. This won't be cheap, even if you do it all yourself, and definitely not if you have to pay for the work. Save yourself the aggravation and transplant another small-block so the car will be as Pontiac intended it. I assume you mean it came with a 305, and being a Firebird and not a Formula or TA it would be a Throttle Body Injection motor, this is basically the same mill as Chevy or GMC pickups use, so you could upgrade to a 350 from a truck and nobody would be any wiser. There are particulars to that upgrade as well, if you want that info, let me know.  

id like to see someone bring the true pontiac v8 into a late model firebird. im a iehard pontiac guy.pontiac v8s were the heart and soul of all pontiac cars.i hated see them go.  

Im the guy who wanted to put the 455 in my 90 Firebird and I was asking questions concerning the cost and problems and Im taking your advise on sticking with a small block. My new question is that a friend of mine wants to sell me his 383 Stroker motor and I was wondering if you could give me some suggestions?  

Let's start with what motor the 90 firebird came with and what trans then I'll work from there, OK? It's just easier, that way I don't have to guess what the car is set up for and I can be more specific.  

Look out for a "L05" block from an early 90's GM van, pickup or 9C1 taxi/police cars. They had 4 bolt main caps and a higher nickel content in the block. The stock engine in my 1990 k5 blazer is the LO5 and it has throttle body injection which looks exactly the same as my friends pickup with a 305. Again, it "looks the same"!   but it's worth a look at because they are very strong engines.

Just my 2 cents