So I have the opportunity to pick up a 455 (unknown milage/cond.) and transmission for $150. I figure I can't go wrong at that price. I'm interested in building a 455 to replace my 350 in my '72 Cutlass.

I know the "J" heads are undesirable. But is there anything else about this motor I should be aware of, such as weak spots or other issues?

Alternatively, I could get a 1971 455 with approx. 78,000 mi for about $500. What's the better choice here??

 

Go for the 74 455 for $150. That's an amazing price!

J heads will serve you just fine unless you want to build a motor for racing.

 

like olds64 said the j headed 455 will be a big upgrade from a 350 but a ga head 455 would be better,i would buy them both.jc

 

I would do the 74. Both wold be considered cores in need of a rebuild and starting cheaper and with a TH400 (most likely) just makes sense, even it's it's a long tail.
You can rebuild the heads, or for not much more money get some aluminum ones and have fun.

 

if the trans is a long tailshaft 400 it wont be much use to him in the cutlass

 

They have been installed in A-body cars before. Besides, it's good trading fodder anyway because someone is always looking for a TH400.

 

Virgin 455s are getting harder to find. 150 is a great price. Nothing wrong with the J heads with good valves and mild clean-up porting. The pistons need to be upgraded to something else for performance. Or build the short block with flat tops and add Edelbrock heads. Easy 450 500 hp with the right cam, pistons, compression, and induction.

 

Thanks for all your comments! It seems now I can get 2 - 455's and trans for $400. Can't go wrong. Just wish I had a bigger garage!

 

Buy the 1971 455 G head engine for $500.


With a new timing chain, a decent mild cam & a Performer intake it will make very good power on pump gas for a cheap overall price.

 

Let us know which one you get. Of course a man can always use another Olds 455.

 

That's way I need a bigger garage. I have hit the jackpot lately on 455's. I could have 4 complete motors right now for a grand total of $1300.