64 gto exhaust decision
 

Ive got a 64 gto, 389, 4 spd man trans, 4 bbl, std exhusat manifolds.
Ive recently pulled this out of a 15 yr storage. The exhaust needs
replacing. What do you all recommend. I dont want to replace the
manifolds with headers. Do I need 2-1/4 or 2-1/2". Does anyone offer
stainless steel? Which mufflers to get for best performance and nice
sound. Any insightful experience would be appreciated!

Pypes?
 

The '64 389/ Tri-Power with RA III [744] cam sure sounds sweet. Might ask around, but previous owner who installed system said it was a piece of cake th install. Car has headers, though. Not sure if any RA manifolds fit '64's, but that's what these bourds are all about, right?BTW...2.5" on ours. If you want stainless, Super Turbos from DynoMax are nice, throaty sounding pieces.

Check out Pypes - many, many options. If you want to stay 100% stock, go with Gardner exhaust.

I was looking at pypes systems, they seem to be aluminized.
Does aluminized last as long as stainless?
The x-pipe systems are for cars with headers, or ra manifolds, right?
The x-pipes are of no use with standard exhaust manifolds, right?
I see in the PY catalog they sell RA manifolds for 1964-72(RPE650H),
would these be worth the investment?, and are they easier to install
than headers? Thanks for any replies :)

There isn't a need to put headers on, or even change to RA manifolds for that matter, unless you're trying to eek out those last couple of hundredths at the track. I'm running log manifolds with the 2 1/2" Pypes X system. With a 462, stock intake, stock cam, stock heads and Summit 2802 cam and 3.08 gears my 4100 lb. Lemans will run in the high 12's. So the logs should be fine on your 389.;)

No, but most GTOs don't see enough bad weather/conditions to make the additional cost of stainless worth the investment, IMO. All my cars have aluminized and look as good as the day they were installed. IF you are really concerned, get the system coated prior to installation. Magnaflow might be you're only option in stainless for a complete system. Others offer stainless mufflers but not pre-bent pipes.

Not necessarily, I am pretty sure PYPES offers the correct downpipes for stock, RA, and longbranch manifolds if you don't use headers.

Again, not necessarily. There are plenty of guys using x-pipes on cars with standard, RA and longbranch manifolds, as well as headers. Probably not as great of a performance gain, but a noticeably different tone. I'd say it's worth the expense if you are doing the whole system anyway.

Haven't installed them myself, but I am planning on it. They can't be any harder than headers, but there are good and bad fitting headers out there. I have heard lots of good things about the RA manifolds.

thanks for the prompt replies. your right, im not trying to eke out every
xtra hp i can. just a street cruise type car. So maybe aluminized would
be all i need. I dont drive but on sunny days.

ok so i can get down pipes for the stock manifolds, and use the x-pipes
system. I see PY offers various different mufflers, which do you
prefer. thx again for the help!!

I went with the aluminized 4 years ago (straight, no H or X pipes) and you can't see a speck of corrosion on them......while I don't drive in the rain (but have when forced to) we do have moisture up here in the Pacific Northwest. The stainless will cost a bunch more than you need to spend.

Oh, and the sound you want is really a personal issue....I went with Magnaflo's and love it.

ok, so i finally bought the pypes aluminized 2-1/2" "X" pipe system
with street pro mufflers. I also bought the downpipes for std
exhaust manifolds.
does anyone out there have pics of the install of this system on a 64 gto.
Or any advice for a rookie mechanic.
thanks for any advice or pics

I have the RA manifolds on my '64. If the motor is still in the car you will have to remove the motor mount bolts one at a time and jack the motor up one side at a time. The passenger's side is cake but on the driver's side you will have to remove the Z bar and disconnect the steering shaft from the coupler and pull it up through the interior enough to get it out of the way. I just went through this when I swapped my heads out.

There are a bunch of install pictures on the Pypes site and many of them are GTO's.

http://www.pypesexhaust.com/pictures.html

We always recommend that you start with the tailpipes and work forward.
Post some pictures if you hit a snag.