455 or 400 in a TA

[BlackTA]

My 1979 trans am currently has a 403 olds and a 3 speed turbo 350 tranny. The engine just blew. Would I be able to install a olds 455 or a pontiac 400 without modification. If not what would I need to modify and which engine would be easier to install. With the 455 am i going to run across problems with my shaker fitting? And is the 455 a reliable engine?

[BlackTA]

My 1979 trans am currently has a 403 olds and a 3 speed turbo 350 tranny. The engine just blew. Would I be able to install a olds 455 or a pontiac 400 without modification. If not what would I need to modify and which engine would be easier to install. With the 455 am i going to run across problems with my shaker fitting? And is the 455 a reliable engine?

[Mr. P-Body]

The 455 Olds and 455 Pontiac are completely different animals. While there have been successful Olds trans-plants, and even some strong 403 builds, the 400 or 455 Pontiac will make more power, reliably.
To put a Pontiac in where an Olds was, you'll need motor mounts, brackets, etc. A donor car would be the smart play.
To put the Olds 455 in, exhaust system and brackets are an issue. The deck on the big Olds is significantly taller than the small one (403 is a "small block" Olds). The Olds is a good engine, but as stated earlier, no match for a Poncho at the same level of tune.

[BlackTA]

where will I see problems with the exhaust and what brackets are we talking about.

[BlackTA]

in other posts Jaggs79TransAm said he had to ditch the heater box where is this piece and does this mean I will have no heat. Also he moved the power steering box does this mean you need a new belt length for the power steering pump?

[Mr. P-Body]

Because the block is so much wider, the stock manifolds MAY fit, but the head pipes will need to be fabricated. To use headers, you will either have to use cheepie-chuggers (fitsall...) or have them custom made.
The brackets for the 455 Olds are for an Olds body. To use the 403 stuff, you may need to move some things around.
I vote for putting a Pontiac in it. Easier, stronger, faster, etc...

[MG12692]

My vote is go with the Pontiac all the way. You will not have any regrets. By having a traditional Pontiac engine you will learn and enjoy this hobby so much more.(you become one of us lol) Even if you plan to sell this car in the future you will find the market increases because you do have a Poncho under the hood. It becomes more desirable to Pontiac fans even though it left the factory with the olds engine. Just my thoughts

[stu72]

old post look at date. :D

[MG12692]

don't I feel stupid..... :)