: Header conversion question



barge master
06-10-04, 10:03 AM
At some point a 500 I have is going into my 80 Fleetwood.Do the larger old style manifolds fit between the frame rails? I'm also considering changing the flanges off a set of BBC headers.Does anyone know which model Chevy tubes fit the Caddy without major hassle?

davesdeville
06-14-04, 02:26 AM
The old manifolds should fit, you may have to cut the end off a bold. I'm not positive, but I seem to remember that's it.

barge master
06-14-04, 06:39 AM
You must mean the upper control arm bolts. They look like they could be a close shave.Thanks for the tip.

Caddy_freak
06-22-04, 09:06 PM
I have had the same question in the back of my mind for a few weeks now, since I've started to rebuild a 500 I boutgh and put it in my 1981 Fleetwood.

Yeah I remember reading about that bolt problem too. Other options I'm told would be to install 472 exaust manifolds, or keep the ones of my 368. I guess these Manifolds are supposed to fit but I don't imagine we would get good flow out of them.

kinda sounds like putting a potato in your exaust pipe don't it?

I may go for the headers too!

anybody else have any ideas or opinions?

barge master
06-22-04, 10:03 PM
Freak,it sounds like we got similar projects in the works.There is no way those scrawny 425/368 manifolds are going on my car.It's a potato effect for sure.I've noticed Chevelle headers are the same for all years 64 to the end.I'm leaning in that direction.I think I might have a pair somewhere in the archives.It's probably going to come down to stuffing them in there when swap time comes,and if it looks like a go,getting some flanges.Trouble is,I'll be lucky to get it in before winter due to all the dumb responsibilities of life.I've also got a 70 472 which I'm thinking of using,it's just the extra coin for the octane.These relatively light cars oughta go like a scalded dog with those engines,and nobody will ever suspect until you leave 'em in a cloud of smoke.:devil: Post an update when you get yours going,it sounds promising.Good luck.

Caddy_freak
06-23-04, 09:35 PM
I sure will, I will take some pics too! to share with all my Caddy brotheren :)

Down here in North Carolina, I have the opposite problem. it's too damn hot to work on it in the summer, Winter is the perfect time for me to do it.