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1981 trans-am engine replacement help
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Posted by: kmains11

i am in the process of rebuilding a 1981 trans-am. right now it has the stock 301 4.9 engine in it. it is shot, i need to replace it. should i replace it with the same engine or go with a bigger motor? id like to go bigger, but i also dont want to get into changing EVERYTHING so it will match up. any suggestions would be great.

Posted by: LS1JAY

I'd go with a 350. Not too sure about what would match up though, but it shouldn't be a hard swap.

Posted by: MadScientistMatt

I'm pretty sure the 301 used the Buick-Olds-Pontiac bellhousing bolt pattern. The 301 is a smogger engine that's pretty hard to get parts for, so I would only replace it with the same thing if you had a Turbo Trans Am you were trying to keep as original as possible. If you are looking for performance rather than preservation, I'd vote for putting a Pontiac 455 in there. It's got a lot more power (upgradable to an ungodly amount of power) and will not require changing very much about the car.

Posted by: LS1 Mopar Turbo

I would get a junkyard 700R4/TH350/400 and a SBC, that would be the smart thing as the after market is HUGE for these, unless of course you want a stock show car.

Posted by: kmains11

hey, thanks for the help. i am currently looking at a 305 high output small block out of a 86 camaro iroc. would this be a good fit or no? i have heard nothing but bad things about the original 301, so im not going to put that back in. anymor suggestions and tips would be great.

Posted by: MadScientistMatt

Well, it'll fit. However, the 350 isn't much more expensive, takes the same amount of effort, and has a boatload more potential. The 305's smaller bores hold it back and limit its options for cylinder head swaps if you later have the budget for it.

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