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Discussion Starter #1
Hey, i just bought a 1969 Lemans GTO clone convertible off ebay (400ci). I currently have a viper, but wanted to buy an older car that I can tinker with and it's relatively affordible (which the viper is not)

Anyway here are my questions.

-Does the convertible ever have a spoiler? if not is it cheese to put it on? If not, where is a good site that sells this stuff?

-The car doesn't have the tach on the hood. It is an automatic...is it a no-no to put a hood tach on for an auto car that has a dash tach?

-It looks like it has lame factory exhaust. Is this a dual exhaust car or were they single? Would dual straight pipes be too loud? What is a common way to do this?

-Are there decent headers and is it worth it?
 

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welcome to the forum
-Yes Judge option convertibles had the spoiler
-Hood tach with dash tach is a bit redundant, but you could change the dash cluster to a non tach
-LeMans was probably single exhaust, GTO would be dual exhaust to the rear bumper
(depending on HP dual factory style exhaust are available and common in 2.25 - 3")
-Headers on Pontiacs are a PITA, as the bolts come up into the block from an angle below and clearances are very tight. The factory style RAM AIR exhaust flow nearly as good as headers and are much easier to deal with.

Some good suppliers are Ames, OPG, & NPD
 

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welcome to the forum
(depending on HP dual factory style exhaust are available and common in 2.25 - 3")

Some good suppliers are Ames, OPG, & NPD
Thanks for the info. I wont bother with headers, but i think dual exhaust is needed. Are there kits or is it easy enough to get a custom job. Do people usully do mufflers, or baffled straight through mufflers, or just stright pipes. I want it to sound mean, but not make my ears bleed
 

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That's mostly a personal preference thing, but you're going to want mufflers of some sort I'd think. Do some searching on youtube for various sounds of Pontiacs running wih different mufflers (there are quite a few out there) and listen for something that sounds good to you.

Bear
 

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Discussion Starter #5
Dude...the flowmaster 817409 sounds nice and is cheap. Best of both worlds :) For a tad above $500 I couldnt even make one for that cheap
 

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kits are easy and fit well. only part you may need to have made are the down pipes from the manifold to the collectors. Anything under 500+ HP should breathe just fine with 2.5's. Pontiac motors have a very distinctive sound, even my wife can tell one coming from two blocks away.... GRRRRRR!!!!
 

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Check Pypes for exhaust parts, especially their header downpipes which are mandrel bent. I've seen dyno testing on exhaust systems and the downpipe out of the exhaust manifold on a Pontiac is critical to making power, spend your money there and everything else is about the sound and price.

Pypes

For mufflers I prefer the Hooker Aerochamber, they flow well and are priced right also excellent construction.

Holley Performance Aero Chamber Products

BTW, rear spoiler was an option on any GTO in '69 and convertibles use a different one than the hardtops, the quarter panels are different between the two body styles so the spoiler is slightly different.
 

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Discussion Starter #10
Ive been looking closer at exhaust, and the downpipes are a good chunk towards a set of Hedman headers. What makes header installation such a big pain in the ass? is it the installation process? or are there more annoying things like having to re-route things or rubbing issues?
 

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I would not go with aftermarket headers; I'd use the reproduction Ram Air/HO manifolds. They are basically OEM cast iron headers, without the PITA of leaks and the fitment issues. You'll need to install the proper oil filter adapter to re-position the oil filter.

One option is to take the car to a local exhaust shop and have them fabricate a system.

You can also buy pre-bent pipe kits from a number of exhaust suppliers (Pypes, R.A.R.E., Waldron's Exhaust or Inline Tube, among others) and choose your own mufflers, or choose one of their muffler offerings.

I like the DynoMax welded Ultra-Flow, the Goerlich XLerator or the Pypes RacePro.
I don't like the sound or the interior vibration that you typically get with Flowmaster mufflers, but everybody's ears and expectations are different.
 

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Discussion Starter #13
PM sent

thanks for the help guys. I called the current owner and he said it has decent dual exhaust, so im not going to worry about it until i get it and can assess what to change
 
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