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Was going to pull the trigger on the ram air exhaust manifold kit on eBay that comes with hardware and downpipes. Question is: the kit I’m looking at has a 2.25” outlet that goes to the 2.5” mandrel bent downpipes. I noticed they also have a 2.5 outlet that runs to 2.5 downpipes.
Are the larger outlets basically for the guys running 3” or should I buy the larger outlet for a better “flow”? Planning on a 2.5” with x-pipe and magnaflow mufflers. Thanks!
 

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The 2.5" mandrel bent downpipes are mainly marketed to work with the aftermarket 2.45" outlet RA manifolds made by PYPES & RARE. IF you want to go back from there with a 3" exhaust system, you can, but honestly unless the engine is truly putting out near 500 hp at the flywheel, seriously doubt the 2.45" equiipped RA manifold 3" mandrel bent pe system will gain anything over a well designed free flowing 2.5" mandrel bent exhaust system. Many cases, with moderate engine builds, all the vehicle is gaining is the extra weight of the larger diameter pipe.

RARE and Pypes also offers 2.25" mandrel bent downpipes which seal a little better with standard sized outlet RA manifolds as well as stock RA manifolds. For many years I've made my own downpipe stubs from 2.5" mandrel bent J-tube. On two of my keeper 455 HO cars, both are being completed for Pure Stock Drags, & both are running original round port manifolds with 2.5" mandrel bent drops, Dynomax long case Super Turbo's & 2.5" mandrel bent aluminized all the way back.
 

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I like the reproduction ram air manifolds - and I'm a guy who's running headers on my own car. If I wasn't interested in "getting everything" out of my engine you can bet I'd be running a set of manifolds.

However, be aware that there are multiple vendors for these manifolds and they are not all of the same quality. Be careful and do your homework.

Bear
 

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My '71 GTO came with a set of bent, dented and rusted headers, which I had zero interest in. Even in good shape, I would have removed them. I wasn't looking for every once of power from the original, going to be stock motor. Some form of originality was more important. I read several articles about the Ram Air exhaust manifolds, liked the looks of them, and bought a pair from Ames. I went with the 2.25" size. Read that they seal better and are easier to install. They've been on for about 1.5 years and still look great. No regrets here. BTW, not a bad price for the manifolds in thread #3 . It appears that you get the exhaust pipes also.
 

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Discussion Starter #7
My '71 GTO came with a set of bent, dented and rusted headers, which I had zero interest in. Even in good shape, I would have removed them. I wasn't looking for every once of power from the original, going to be stock motor. Some form of originality was more important. I read several articles about the Ram Air exhaust manifolds, liked the looks of them, and bought a pair from Ames. I went with the 2.25" size. Read that they seal better and are easier to install. They've been on for about 1.5 years and still look great. No regrets here. BTW, not a bad price for the manifolds in thread #3 . It appears that you get the exhaust pipes also.
I have Zero interest in my headers that are currently installed. I mangled them to clear the rag joint while adding power steering, they bounce off the upper arms and rub on the Z bar underneath. There is one particular passenger side bolt I plan on melting, pressing it into a .308 casing and firing into the pacific ocean. Hopefully it gets eaten by 1,000 animals and thus being shi* out a thousand times. Ordered the manifolds.
 

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Feel your pain. am dealing with a local customer/long time friend whose drivers side header as well as frame & z-bar were mangled in an accident several years back. Frame has been professionally repaired and body is on roller cart getting 1/4 panel & trunk replacement. We'd both love to see the car ditch its 3 tube headers & get a set of RARE oversize manifolds & mandrel bent down pipes, but till metal work & bodywork is complete, such pieces have to wait.
 

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I have Zero interest in my headers that are currently installed. I mangled them to clear the rag joint while adding power steering, they bounce off the upper arms and rub on the Z bar underneath. There is one particular passenger side bolt I plan on melting, pressing it into a .308 casing and firing into the pacific ocean. Hopefully it gets eaten by 1,000 animals and thus being shi* out a thousand times. Ordered the manifolds.

Tell us how you really feel about your headers. LOL And.......you would probably have a Hazmat Team at your doorstep for shooting the iron slug into the ocean waters, so do it at night, do it discreetly. LOL

As has been told by many stories here on the forum, some brand headers and the cars year and engine/trans combo's just don't seem to fit well at all. Everything from denting them to fit to cutting the pipes and re-working them have come up. But then some guys have zero fitment problems. RA exhaust manifolds just seem the best way to go unless you have to just have headers or want max performance.

I have not installed them, but I got the Doug's headers as they are said to be one of the best fitting. Not inexpensive in my book and even pricier with the ceramic coating on them. My '68 uses that swivel link Z-bar (pic on left) which is a bit bulky and the Doug's headers said to go with the earlier 1964-65 straight tube Z-bar (pic on right) which does not have the swivel link. I'll mock it all up and modify/adjust my clutch linkage as needed - which will be easier with the nose off the car where I can get to everything.
 

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I have Zero interest in my headers that are currently installed. I mangled them to clear the rag joint while adding power steering, they bounce off the upper arms and rub on the Z bar underneath. There is one particular passenger side bolt I plan on melting, pressing it into a .308 casing and firing into the pacific ocean. Hopefully it gets eaten by 1,000 animals and thus being shi* out a thousand times. Ordered the manifolds.
You made a good decision. I don't think you'll be sorry at all. Couldn't get mine off fast enough. Where I could, I used my saw-zall on them. The bottom of the tubes were becoming flattened by bottoming out. Have no idea what someone had been hitting. Couldn't have been good for the motor at all. Maybe I shouldn't repeat this, because I'm trying accurately to recall what I read about headers a few years ago, and I don't want to be misleading. It seems that a major magazine did a test on a Pontiac engine, using a log type exhaust manifold, Ram Air manifold and long tube headers. The log manifold was terrible for performance. If I recall it correctly, the Ram Air manifold worked quite well. Almost every bit as good as the headers, until you reached 450hp or more. Then the tube headers excelled and the motor performed better with them. At least I think that is my recollection. After reading that, it was a no brainer for me.
 

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Discussion Starter #11
You made a good decision. I don't think you'll be sorry at all. Couldn't get mine off fast enough. Where I could, I used my saw-zall on them. The bottom of the tubes were becoming flattened by bottoming out. Have no idea what someone had been hitting. Couldn't have been good for the motor at all. Maybe I shouldn't repeat this, because I'm trying accurately to recall what I read about headers a few years ago, and I don't want to be misleading. It seems that a major magazine did a test on a Pontiac engine, using a log type exhaust manifold, Ram Air manifold and long tube headers. The log manifold was terrible for performance. If I recall it correctly, the Ram Air manifold worked quite well. Almost every bit as good as the headers, until you reached 450hp or more. Then the tube headers excelled and the motor performed better with them. At least I think that is my recollection. After reading that, it was a no brainer for me.
I think I'm going to sawzall mine out too :grin2:! Next question is: did you high heat paint yours or did you buy them coated from Ames? I was thinking about high heat priming/painting them grey just because I know the rusty look will bug me. Pics attached of recent work:
 

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I think I'm going to sawzall mine out too :grin2:! Next question is: did you high heat paint yours or did you buy them coated from Ames? I was thinking about high heat priming/painting them grey just because I know the rusty look will bug me. Pics attached of recent work:
I was just thinking about this "engine plate" .... is it just me or are you nervous as hell about lifting a 700 motor by four 5/16 carb studs?

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I was just thinking about this "engine plate" .... is it just me or are you nervous as hell about lifting a 700 motor by four 5/16 carb studs?

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Supposed to read 700 pound motor

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Yeah, I am too. Even though I have one of those plates I've never used it. I always use one of those hoist "levelers" and bolt the chains to the front and rear of both heads.

Bear
 

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Yeah, I am too. Even though I have one of those plates I've never used it. I always use one of those hoist "levelers" and bolt the chains to the front and rear of both heads.

Bear
Off subject, but if I could ask about your P/S pump brackets. Do you have one large bracket and one small one for the alternator (on the front) ?

Thanks

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I think I'm going to sawzall mine out too :grin2:! Next question is: did you high heat paint yours or did you buy them coated from Ames? I was thinking about high heat priming/painting them grey just because I know the rusty look will bug me. Pics attached of recent work:
Your motor looks great. What I did to mine is, I used the VHT primer and a VHT grey paint. Followed their instructions for application and 1.5 years later, they still look very nice. With working on the car several times a week, I see them often, and no signs of rust whatsoever. They actually look new. With the factory a/c components, I don't see a lot of the passenger side top. But I do see it when on the lift from below. The driver side isn't hidden from view and looks very nice. No regrets. I'd paint them the same again.
 

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Off subject, but if I could ask about your P/S pump brackets. Do you have one large bracket and one small one for the alternator (on the front) ?
I'm using the original bracketry on my '69, but it's not "stock" (long story). There's a large-ish bracket that bolts to the drivers side head. On the front of the pump itself there's another bracket bolted to the pump (with some spacers to make it square to the pump shaft). One hole on this bracket takes the main mounting bolt for the pump. On the back of the pump housing there's a stud that sticks through a slotted hole in the bracket that's mounted to the head. The slot allows the pump to pivot on the mounting bolt so you can adjust belt tension. There's a third bolt that likewise goes through a slotted hole in the bracket that bolts to the front of the pump, also used in conjunction with the one on the back side for adjusting belt tension. There's a 3rd piece, sort of a dog leg looking bracket that has 3 bolt holes in it. Two of them go under the bolts on the front of the pump (the adjustment bolt and the mounting bolt). The 3rd hole on the end of the dog leg slightly above the p/s/ pump mounting bolt is where the lower alternator bolt goes.

Bear
 
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