1972 LT-1 Exhaust System for judging ?

[Marc B.]

Restoring my early 1972 LT-1 for 2014 Flight Judging.

Big question on exhaust: will an ``Aluminized exhaust`` system pass judging ? Or do I have to go with a carbon steel one ? Any recommendations on suppliers for correct parts ? I usually order my stuff from Corvette Central...
Thanks for the help,

[Don H.]

Re: 1972 LT-1 Exhaust System for judging ?

Hi Marc
Aluminized exhaust is a standard deduction item. Item 6 on the Standard deduction guide. So, aluminized "will pass" judging with a 25% deduction from the total originality points. If the judges are really sharp, and you use normal carbon steel hangers, clamps and brackets, your deduction would be slightly less than 25% of originality points. As to whom to buy from, we C2 guys like CCs systems. I imagine that C3s are the same. C3 guys will speak up.

[Terry L.]

Re: 1972 LT-1 Exhaust System for judging ?

I bought a gardner exhaust system for my LT1 http://www.gardnerexhaust.com/1970-c...st-system.html
I haven't had my car judged yet but I understand the Gardner exhaust is as close to original as available after market. The fit was perfect on my car. I am planning on buy another set for my other LT1. The inlet pipe to muffler is not welded unlike the original exhaust, but you can weld it once you get it fitted to match original system.

[Patrick H.]

Re: 1972 LT-1 Exhaust System for judging ?

Hi Marc
Aluminized exhaust is a standard deduction item. Item 6 on the Standard deduction guide. So, aluminized "will pass" judging with a 25% deduction from the total originality points. If the judges are really sharp, and you use normal carbon steel hangers, clamps and brackets, your deduction would be slightly less than 25% of originality points. As to whom to buy from, we C2 guys like CCs systems. I imagine that C3s are the same. C3 guys will speak up.

Don,

While I'm a fan of the CC system for Corvettes that are going to actually see the road, and on a point-per-dollar basis, the actual hit in judging for early C3's is about 50%.
There are issues with finish, configuration, and possibly dating depending on the judge.

Gardner systems also have a few issues and are not perfect. Finish, configuration and even dating (for the judges who deduct for it) are issues with this system too, just less issues.

There is no aftermarket system that will "pass judging." It's a matter of how much do you want to spend, and what point hit do you want to take.

Patrick

[Don L.]

Re: 1972 LT-1 Exhaust System for judging ?

I bought a gardner exhaust system for my LT1 http://www.gardnerexhaust.com/1970-c...st-system.html
I haven't had my car judged yet but I understand the Gardner exhaust is as close to original as available after market. The fit was perfect on my car. I am planning on buy another set for my other LT1. The inlet pipe to muffler is not welded unlike the original exhaust, but you can weld it once you get it fitted to match original system.

I've read where the CC system is popular. I had heard that the Gardner system had improved likeness features over the CC system. I also heard of some horror stories when it comes to customer service on the Allen system. I am VERY happy with the Gardner system and accept the deducts for aluminized pipes, non-embossed mufflers, NTFP inlet, etc. Seems to me that if I had the carbon system, I'd lose points for condition AND the system would rot out, just like the old days.

I did weld my exhaust pipe to my inlets and have attached a photo of the finished product. (Sorry Patrick - these were taken before I installed those swannky part number labels ). The labels add a nice finishing touch, in my opinion.



IMG_3893.JPG

IMG_3887.jpg

[Edward J.]

Re: 1972 LT-1 Exhaust System for judging ?

Marc, My 72 went through regional judging this past spring and I have a Gardner system on my car judging was judged by a couple of regulars here on The discussion board and the total deduct for my car was 10 points out of 28 total originality points. I consider that to be pretty close for most of the exhaust systems manufactured today by the corvette venders. As the guys here all agree there is nothing like an original system. I would like to say that the Gardner system is one of the best fitting systems made. I have installed many different systems on corvettes over the years, and most other systems require a lot tweaking.

[Joseph M.]

Re: 1972 LT-1 Exhaust System for judging ?

I have Gardner systems on my 67 427-390 and 70 Chevelle SS396. We welded the muffler as close to factory as currently possible on the Vette. The fit on both systems was quite good. The Vette received a regional Top Flight this year with no major deduct for the exhaust. Had previously used Allens' systems and experienced some installation problems.

[Ross F.]

Re: 1972 LT-1 Exhaust System for judging ?

I had a great 72 LT-1.
I found an original exhaust system for it hanging in the attic of Tracy Corvette in Roseville Michigan.
The originals had crimped bends. I don't think anyone does that repro.

[Joe L.]

Re: 1972 LT-1 Exhaust System for judging ?

I had a great 72 LT-1.
I found an original exhaust system for it hanging in the attic of Tracy Corvette in Roseville Michigan.
The originals had crimped bends. I don't think anyone does that repro.

Russ-----


You found an original SERVICE exhaust system for it at Tracy. One could never obtain a PRODUCTION type, original exhaust system for any 1969-72 Corvette. The SERVICE and PRODUCTION systems differed in configuration.

As a matter of fact, the only 1963-72 Corvette for which one could ever obtain a SERVICE exhaust system that was identical to PRODUCTION was 1964-68 with N-11 exhaust. No others.

[Ross F.]

Re: 1972 LT-1 Exhaust System for judging ?

Don't know what to tell you, but I did. The car was judged top flight by the stingy Michigan chapter in west bloomfield seven years ago.
The pipes where crimped and still had part number stickers.

[Don L.]

Re: 1972 LT-1 Exhaust System for judging ?

Russ-----


You found an original SERVICE exhaust system for it at Tracy. One could never obtain a PRODUCTION type, original exhaust system for any 1969-72 Corvette. The SERVICE and PRODUCTION systems differed in configuration.

As a matter of fact, the only 1963-72 Corvette for which one could ever obtain a SERVICE exhaust system that was identical to PRODUCTION was 1964-68 with N-11 exhaust. No others.

Joe - perhaps it was a "take off", maybe traded to Tracy for side pipes, etc?

Does anyone have a photo of the (original) crimps Ross is mentioning?

[Terry M.]

Re: 1972 LT-1 Exhaust System for judging ?

I am pretty sure the Gardener system, has a reasonable facsimile of the crimps on the 2 1/2 -inch system. No crimps on the 3-inch system. No foto here come to KC this summer.

[Ross F.]

Re: 1972 LT-1 Exhaust System for judging ?

I think I have a photo somewhere. I sold the car to someone in Canada 6 years ago. But the goofy thing about the LT-1 exhaust was the 2 into 2 1/2 transitions. I have never seen a carbon steel crimped bend on a repro.

[Joe L.]

Re: 1972 LT-1 Exhaust System for judging ?

Don't know what to tell you, but I did. The car was judged top flight by the stingy Michigan chapter in west bloomfield seven years ago.
The pipes where crimped and still had part number stickers.

Ross-----

Was it a used system? Were the rear pipes welded to the mufflers at the mufflers?

[Joe L.]

Re: 1972 LT-1 Exhaust System for judging ?

I think I have a photo somewhere. I sold the car to someone in Canada 6 years ago. But the goofy thing about the LT-1 exhaust was the 2 into 2 1/2 transitions. I have never seen a carbon steel crimped bend on a repro.

Ross-----

All 1966 -80 Corvette small blocks used exhaust manifolds with 2" outlets. So, all of those with 2-1/2" exhaust (L-46, LT-1, L-82) used the 2" to 2-1/2" transition. On earlier cars the pipes were swaged. On later (from about 1973 and SERVICE after about 1973), a 2" short section was welded to the 2-1/2" section.

All big block were 2-1/2" for their entire length except 1969. All 1969 big blocks used a 2" exhaust. So, there was a short 2-1/2" section from the manifold which transitioned to a 2" pipe for the rest of the system.

The Gardener system has the "crimped bend" configuration. However, it is simulated and, thus, not exactly as-original.