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Author Topic:   455 Rocket Motor in a Firebird
Racer B
Dirt Roller

Total posts: 8
posted December 26, 2001 06:16 PM
Ok maybe I am stepping in a puddle of dog poop, but was given a free 455 motor (that runs)-anybody ever put one of these in a mid-70s Firebird. Not sure whats involved, but thought since this was free and running might make a good emergency back up. Any thoughts?

AC156
Dirt Moderator

Total posts: 254
posted December 26, 2001 06:48 PM
What kind of engine are you running now? If you are running a sbc, then the 455 wont bolt up to the chevy trans. Buick, Oldsmobile, and Pontiac all have a bolt pattern that is different than chevrolet's.

[This message has been edited by AC156 (edited December 26, 2001).]

hesseracing
Dirt Full Roller

Total posts: 48
posted December 29, 2001 10:05 PM
what type of 455 is it a pontiac or a olds? if its a pontiac u can get a pontiac tranny a 300 i believe. it will bolt up to a chevy and the pontiac 455. you can also check they now make plates that make many eng/tranny mixes work. my buddy runs a pont 455 in his 76 firebird with the 300 tranny. he runs good with it the drawback is the weight on the front of the car. you might be better off selling the motor and putting a 350 together as a backup.

hesseracing
Dirt Full Roller

Total posts: 48
posted December 29, 2001 10:07 PM
ok, i see thats its a olds rocket. id sell it and get a 350 for a backup. just my opinion.

ryan
Dirt Freak

Total posts: 266
posted January 17, 2002 01:10 AM
AC156- There are transmissions out there that accept oldsmobile and chevy bolt patterns.

AC156
Dirt Moderator

Total posts: 254
posted January 17, 2002 09:36 AM
Ryan, i know that there are transmissions that have cases with dual bolt patterns that allow you to bolt up to a chevy or pont, olds, buick. I am not saying that it cant be done. What i am saying is that, if he doesn't have one of those transmissions, then he would have to find another one if he wanted to run the 455. I have ran a pontiac trans behind a sbc. We drilled out the case at the top. You can also make a bracket for the two middle bolts. But if i was running a chevy trans, then i wouldn't want to drill out the case just so it would bolt to a olds engine.
Racer B, What kind of trans. are you running?

Also, like hesseracing said, they do make adapter plates that allow you to mix the bolt patterns. The reason that we didn't run a adapter is just because we are on a tight budget and we didn't want to pay for one.lol. A buddy of mine who owns a salvage yard showed me an old magazine article that told how to drill out the case and make it work, so that is what we did. If a pontiac 300 will bolt up to a chevy and a pontiac, like hesseracing said, then it should also bolt up to a oldsmobile. Buick, olds, and pontiac have the same bolt pattern, at least in the late '70s early '80s they did.
Sorry if i caused some confusion.

[This message has been edited by AC156 (edited January 17, 2002).]

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