Mark71

Hey... I've got a question. I am planning (somewhere in the next 2-3 years) to build a new 350 or 455 for my 71 Cutlass Supreme Convertible.

Right now, I have a 71 350 that is .30 over. Because I am planning to upgrade to a built 350 / 455, I don't want to spend too much on upgrades for the existing 350.

BUT - I have a nasty exhaust leak in the passenger's side manifold. It was bad when I got the car but seems to have gotten worse. On top of that I have a muffler shop special exhaust system which is rusted pretty badly and not well supported at all. The rust holes help cover the "pfiff pffif" of the exhaust leak at the head, though.

Here's the question:
Does anyone have experience with the Flowtech headers p/n 11150-FLT? Will they fit a CS convertible with floor shifted automatic??
http://www.summitracing.com/parts/BIG-11150FLT/

I read a few posts on here and I know the mythical "does not fit supreme models" is crapola, but I want to make sure. Some say "will not fit floor shifted automatics." Is that true?

I'm going to replace the entire exhaust system with a header-back 2.5 inch, flowmasters, etc. but the headers are still a big question...

Thanks!

Beob

Im not sure how well they fit in a 71, but from my exp, they tend to fit better on a big block. Also Flowtech is not known for making quality headers, they are very inexpensive, and you get what you pay for.

Mark71

Yeah, I figured as much, but for less than 600 bucks, it is the only thing I can find that fits a convertible, floor-shifted automatic.

rocket1889

hey ive got a 71 cutlass converted 4-speed 350 rocket...ive got flowtech headers and a pypes 2.5 inch full exhaust

i choose the flowtechs for price...i paid $285 from summit...when i took them out of the package they looked weird to me because the header doesnt sit flush against the head...the header flange is raised up some from the welds...i was going to return them but figured wht the hell and installed them

when i first got them i bashed them a lil here on the forum but they have been installed on my car now for over 6 months and no leaks nd i am very pleased with them... had a nice sound to when i started her up open headers lol

id say get them

Indy_68_S

I'm confused by this statement...
I'd think a floor shift auto would be the easiest thing to fit headers on... No clutch or column-shift linkage...

Mark71

Crap. Sounds like you got the "high quality" version. The ones I was looking at are like 155. I just don't want to spend 600 on headers for an engine I am planning on replacing in the next couple of years. I would actually even consider keeping the manifolds, but I think one is cracked.

Yeah, you'd think so, but that's the problem. There's still a column shift linkage, in fact the column actually turns when you shift on the floor. It sets the ignition lock so that you can't start in neutral or shift out of park when the ignition is off.

That stupid linkage makes changing the brake booster a pain... I had to disconnect it to get my new booster in.

Indy_68_S

Ahhhhh. You kids and your newfangled 1971 technology with its column locks....

I was coming from the '68 point of view where with a floor auto there's only a cable from the shifter to the trans. No column lock. Thanks for the explanation...

rocket1889

hey was just reading about you even just sticking to manifolds...ive got a 71' 350 pair you can have for $50 but at the end of the day all said and done id get the $155 flowtechs nd b done with it

Mark71

Yeah, I think I am going to go that route (Flowtechs) for the time being. One reason I don't stick to manifolds is also that I'd have to have them machined down to make sure they are flat. Add that to the fact that I'd need downpipes AND the fact that I should pick up a "couple" of HP through headers... Well, you see where I am going with this.

If I were really trying to keep it stock, I'd spend the money for the manifolds, but the car's already far from stock as is. Thanks for the offer, though.

Mark71

Hey - I've seen a few people talking about it already, but I want to make 100 percent sure because there doesn't seem to be a definite answer...

The mythical offset and restriction to headers on a Supreme Convertible is just a myth right??? I can order headers for a Cutlass because there isn't any difference between the frames and engine mounts from a base, S, or Supreme (convertibles, of course) in 71...?

Can anyone confirm that??? I really want this to be true and I am so tired of seeing that it "does not fit Cutlass Supreme because of engine offset" or whatever.

Thanks!