Hitman's Pontiac Trans Am Forum

Trans Am Information => Trans Am Tech => DriveTrain => Topic started by: SavingTheBird76 on February 09, 2012, 11:36:55 PM

Title: Which Ram Air manifolds do I need?
Post by: SavingTheBird76 on February 09, 2012, 11:36:55 PM

Looking to get my 350 running..sporting the #11 1969/1970 heads...1971 lemans project
I know they don't have the bolt holes on both ends...but not sure which type are correct fitment.
Multiple versions show no holes on the ends...
Pics appreciated.
Thanks.

Title: Re: Which Ram Air manifolds do I need?
Post by: SavingTheBird76 on February 10, 2012, 09:22:02 PM

Fits 68-72 GM a-body with d-port heads. Also fits 70 1/2 - 81 f-body. ***For those using cylinder without end bolt holes (i.e. #7K3, 7M5, etc) we have a fix that doesn't require brackets or addl machining on heads. there is a 40.00 shop fee for this mod to the factory headers. Request in "order comments" when you checkout)

I may be going Chevy if you guys don't help me out. ;)

Title: Re: Which Ram Air manifolds do I need?
Post by: hada76 on February 10, 2012, 09:31:50 PM

how about calling them with your motor specs?

Title: Re: Which Ram Air manifolds do I need?
Post by: SavingTheBird76 on February 10, 2012, 10:44:24 PM

Scares me that the description says modification necessary for heads with no end bolt holes.
Hoping someone bought a set and can give me an answer.
$400 seems silly to me when a complete crate motor is $1650 delivered to my door.
A lot less headaches going with a Chevy motor and headers. :(

Title: Re: Which Ram Air manifolds do I need?
Post by: 72blackbird on February 11, 2012, 02:35:40 AM

I'm building a 389 for a 65 GTO- the car has no. 11 heads, ceramic-coated RARE manifolds and a 2 1/2" Pypes exhaust. These heads have 6 exhaust bolt holes, but due to the design of the manifolds only 5 of the 6 bolt holes are used. I know these manifolds fit these heads because I installed them on the first 389- there are no problems with bolting the manifolds to these heads.

RARE also has these manifolds for a 2nd gen F-body- I plan to use them on my 75 Formula 400. These same manifolds will fit on your 71 Lemans as well.

Geno

http://www.ramairrestoration.com/catalog/product_info.php?cPath=31_2_21&products_id=40

Title: Re: Which Ram Air manifolds do I need?
Post by: Burd Turd on February 11, 2012, 11:36:58 AM

I called RARE for mine, and after talking to them for an hour they sent the wrong dr side, then hung up on me when I told them about it, I would not buy them again if you put a gun to my head.

Title: Re: Which Ram Air manifolds do I need?
Post by: 72blackbird on February 11, 2012, 03:17:39 PM

I can sympathize with anyone struggling to get the right parts on their car- it can be an ordeal, and we don't really need the grief when we're building our Firebirds and T/As to enjoy life anyways. But I've also heard plenty of horror stories too and been jerked around a few times too when it comes to parts, so I feel your pain.

I lucked out 20+ years ago when I ordered a set of Hooker comps for my 72 Bird- they went right on the 400 w/ no problems, cost like $100 + shipping (I know they cost more now), and made a noticeable difference in power. If the price goes up any more than the $400+ they want for cast iron headers, I'll just get a set of Hedman 28150's and have them ceramic coated- about the same price, but lighter and make more power.

Geno

Title: Re: Which Ram Air manifolds do I need?
Post by: Burd Turd on February 11, 2012, 03:56:21 PM

I would suggest talking to Perf Years, or Ames, instead of the RARE buttheads. I ran in to the owner at the Ames tri nats, and told him, he didn't know what to say.

Title: Re: Which Ram Air manifolds do I need?
Post by: SavingTheBird76 on February 11, 2012, 08:57:26 PM

Thanks for the link Geno...and for the opinions on the purchases bird.
Spending $400+ on exhaust manifolds for a motor of unknown condition seems like a stretch for me...
Tough choices.

Title: Re: Which Ram Air manifolds do I need?
Post by: Burd Turd on February 11, 2012, 11:12:55 PM

I took it a step further, I had them bored to 2 1/2 ", and ported, and cer. coated. $650, but they will be on there forever. then comes a nice exhaust, and mufflers, and some 2 1/2' tips.

Title: Re: Which Ram Air manifolds do I need?
Post by: 72blackbird on February 12, 2012, 11:25:45 AM

I believe the owner of the 65 GTO did purchase his Ram Air exhaust manifolds from Ames- he swears by them and orders most of his restoration parts from them.

I personally wouldn't use cast iron manifolds on every Pontiac I own, since they are heavy and don't make as much power as a tuned header. But they are ideal for a correct appearance on a factory musclecar, like on my 75 Formula 400, and will definitely improve performance over the factory log-style exhaust manifolds.

The 2 1/4" version is cheaper than the 2 1/2" version- I suspect they both perform about the same.

Geno

Title: Re: Which Ram Air manifolds do I need?
Post by: SavingTheBird76 on February 13, 2012, 10:26:02 AM

Can anyone do some math for me?
Found a set of 400 heads,screw in studs,large valves,101 cc compared to 93cc of my 11's.
How much will I lower compression by going with the larger head volume.
Thanks.

http://www.projectpontiac.com/ppsite15/compression-ratio-calculator

Figured it out...7-1 compression..bad idea. ::)