I am starting the restoration on my 78 T/A and I have two engine choices that I can go with. I have a 455 that has been bored .30 over and I have the 350 that came out of it. Any opinions on which one would be a better choice. p.s. I already went out and bought some 72cc Edelbrock performer rpm heads, can these be used for both engines?  

The 455 will have a lot more torq then the 350 but if you build it right the 350 will handle more rpm.Yes the edelbrock performer heads will fit both engines.Are they both true pontiac engines. Is the 350 original engine for the car.I always have prefered the 350 over the 455 but that's just me.Also what is the intended use and budget you want to spend.  

I'll go with Pontiacman8 on this one, both engines have their merits and it depends on what you want to do with the car. What gears do you have? 4 speed manual or auto?
Steve  

the 455 came out of a catalina and the 350 is the original engine of the car and it is an automatic and I have no idea what the gears are, it has the original rear end. I want to restore it so I can drive it around town and maybe take it to the track every now and then. I am trying to stay at about a $5000.00 budget for the engine but if it takes more than that I dont mind spending it.  

I would stick with the 350 what is the code on the heads witch can be found on the center exhuast port. Also how much power are you wanting.  

Guys, since Pontiac stopped production of their 350 in 77 and stopped putting them in cars at the same time, if it is the original engine it must be a Chevy 350, which was available in 78. Can you get us the VIN number and the block and head #'s so we can tell what you have?
Steve  

HI GUYS, SORRY IT HAS TAKEN ME SO LONG TO REPLY I TOOK A SMALL VACATION TO ATLANTA. NOW ABOUT THE BLOCKS, THE 350 IS A CHEVY ENGINE BUT IT TURNS OUT I CANT USE IT BECAUSE IT HAS A CRACK IN IT SO I AM GONNA USE THE 455. NOW I HAVE ANOTHER QUESTION, I JUST BUMPED INTO A GUY WHO IS SELLING A 428 FOR 100 BUCKS THAT CAME OUT OF A CATALINA WHAT DO YOU THINK ABOUT THIS ONE VS. THE 455.
BY THE WAY GUYS MY NAME IS OMAR.  

Omar, the 428 is generally considered the better performance motor, simply because the 4" stroke revs easier than the 4.21" stroke of the 455. However the two can be combined, the 428 crank and 455 block I believe yields a 440. I forget the details, if I have time to look them up, I'll post them.
Steve