Early Pontiac GTO's had a 400 cu. in. restriction but you could order a larger engine in a Tempest...

Did Olds have a similar feature ..?

 

Never mind Olds, Pontiac did not have that feature. GM had a corporate 400 cu in limit on ANY A-body car through the 1969 model year. That's the whole reason for the Hurst/Olds (despite the fact that the 455s were, in fact, bolted in on the Olds assembly line). You could not order a factory installed engine larger than 400 cu in in a Tempest, Cutlass, or any other A-body, at least not through normal channels. Jim Wangers certainly had a few built, but they were officially dealer cars like the Royal Pontiac 421 cars. And of course there were COPO 427 Chevelles.

There are rumors of factory-installed 425s in early 442s, but to date not one scrap of proof has surfaced.

 

Well put, Joe!

 

I worked for a Buick dealer in 1965 when the Skylark Gran Sport came out. Of course Buick had their basic 401 they used in the Gran Sport. They claimed it was bored differently to get 400 cubic inches. Possible maybe but I doubt it. It wouldn't take much of and underbore to eliminate 1 cubic inch from 401. The dealership prepped one and ran it with 4:88 gears. Sweet car that I would love to have today. With those small valves (they didn't call them nailheads for no reason) they still would not outrun the GTO's. We didn't have anybody running 442's but I think they would have beat us.

 

I just called Pontiac Historical Society and they said there were NO engines over 400 cu in in the early years...

I've seen Tempests with the larger engine, it must have been a dealer or owner installed ...

 

There was all kinds of under the table\back door dealings going on back then for the factory sponsored race programs and even specially "prepped" cars provided for magazine reviews - But officially the limit was at 400cu.

Also- back then, when an engine blew up 2 or 3 years after the car was new, it wouldn't have been a stretch to imagine the owner requesting or paying extra to get a bigger replacement motor put back in- and now 40+ year later, its easy for people to dream up that they were in there from new...

 

You mean the 455 in my 64 Cutlass isn't factory?

 

Yeah, I always chalked that up to roundoff error.

 

I always thought they just stamped it different, a m instead of an L ...

 

A friend of mine raced for dodge back then and they sent him a set of stamps for the blocks they would recieve ...