Exhaust System Replacement

[Frederick W.]

I'm planning to replace the exhaust on my 63.
In reviewing the TIM/JG, JRM, and judging sheets, I gather that for full points I should buy a welded muffler carbon steel system with carbon steel clamps and hangers.
However, carbon steel, of course, rusts.
Oddly, it seems that there is a 50% originality deduction for Stainless and only a 25% deduction for aluminized (even though neither were original). And the deduction would apply only to the the pipes/mufflers if I use rustable steel clamps.
So, if my calculations are correct, I could use an aluminized system with carbon steel clamps/hangers, and get a fairly minimal deduction:

10 points for originality of pipes/mufflers
so only 2.5 point loss for aluminized or 5 points for stainless?

Would appreciate someone with experience in the judging process to confirm the above.
Any suggestions regarding suppliers/vendors or other tips for exhaust replacement?

Fred

[Joe L.]

Re: Exhaust System Replacement

I'm planning to replace the exhaust on my 63.
In reviewing the TIM/JG, JRM, and judging sheets, I gather that for full points I should buy a welded muffler carbon steel system with carbon steel clamps and hangers.
However, carbon steel, of course, rusts.
Oddly, it seems that there is a 50% originality deduction for Stainless and only a 25% deduction for aluminized (even though neither were original). And the deduction would apply only to the the pipes/mufflers if I use rustable steel clamps.
So, if my calculations are correct, I could use an aluminized system with carbon steel clamps/hangers, and get a fairly minimal deduction:

10 points for originality of pipes/mufflers
so only 2.5 point loss for aluminized or 5 points for stainless?

Would appreciate someone with experience in the judging process to confirm the above.
Any suggestions regarding suppliers/vendors or other tips for exhaust replacement?

Fred

Fred-----


I don't think there's a system on the market today that will get you full points on originality if your car is judged by a very "in-the-know" judge. However, I think the system available from Gardner will probably come the closest. Of course, you better get the car judged pretty quickly after you install the system or you might lose condition points for the rust that's sure to develop if you drive the car.

[Frederick W.]

Re: Exhaust System Replacement

Thanks Joe,

I did see an ad for Gardners, maybe in the driveline.
I was thinking, though, of getting an aluminized system since the car is a driver, not a trailered car. I don't know if Gardner makes this. I was considering the Corvette Central product.
I assumed that the CC exhausts would get full originality points if I bought their carbon steel units, and lose 2.5 points for aluminized. From what you say I would be docked some additional originality points (over and above the aluminized issue) for, presumably, something else not quite correct about their system?

Fred

[Joe L.]

Re: Exhaust System Replacement

Thanks Joe,

I did see an ad for Gardners, maybe in the driveline.
I was thinking, though, of getting an aluminized system since the car is a driver, not a trailered car. I don't know if Gardner makes this. I was considering the Corvette Central product.
I assumed that the CC exhausts would get full originality points if I bought their carbon steel units, and lose 2.5 points for aluminized. From what you say I would be docked some additional originality points (over and above the aluminized issue) for, presumably, something else not quite correct about their system?

Fred

Fred------


The Corvette Central aluminized or standard steel systems are excellent. However, I don't think that a savvy judge would assign full originality points to even one of their standard steel systems. You have one thing going for you, though. A lot of the savvy judges are "portly" so they might not be able to get far enough under the car to fully observe the system.

I believe the original GM systems were die-formed. This created "wrinkles" at the bends and "flattened" configuration in other areas (for improved ground clearance). I don't think the "flattened" cross sectional configuration seen in original pipes could have been created any other way than die-forming. I'm not aware that anyone today manufactures pipes exactly like the originals, although Gardner has worked hard to come close. That's because die-forming for the limited restoration market would likely be prohibitively expensive.

[Grant W.]

Re: Exhaust System Replacement

Hi Fred
If you are not worried about points or judging then buy the aluminum ones from Allens or CC. You can drive it in the rain and or winter. But I wouldn't,
If you are going to get it judged. Then buy the best available reproduction as to factory specs. It would have to be carbon steel and the bends and folds. I wouldn't worry about rust as I assume your car will be in a garage. The amount of rusting will be minimal. It can be taken off with rust mort.
I helped a fellow NCRS member restore his 68 B/B and he used Gardners exhaust system. He got a 1 point deduct. He forgot to weld the mufflers to the single one piece pipe system. He was going to put a clamp on it but I told him it was not right. So I just told him just put 4 tack welds to hold in place, get it judged and when he gets home do a proper weld around the pipe. Incidentally Jeff's 68 corvette scored if I recall 97.6

Gardners has the proper bends, flattening of the pipes. If Joe's recommendation as being the closest to factory configuration I will also concur it is one of the best. Talk to Eric Gardner [gexhaust@frontiernet.net]
I don't have a pot belly yet so anytime I get to judge chassis I can slide under the car and look at the exhaust systems.
Anyways I hope this helps out your decision.
Grant

[Stuart F.]

Re: Exhaust System Replacement

I've had a Aluminized system on my 63 for 18 years now which is completely welded and flattened, etc. I'm not sure what brand I have, but it has held up real well over the years with just a slight amount of seam rust starting to show in a few places. I also replaced the pipe hanger clamps with SS some years ago. This system is about the 4th one I put on the car since new and, as you might imagine, I got tired of replacing them on a relatively low mileage car (44k). They carbon steel rusts just sitting in your garage, even with a sealed concrete floor. For a number of years, I also had a heavy vinyl cover on the floor.

If I had any complaint about my system, it would be with the mufflers. They never would fit well using 63 rear hangers which, in themselves, produced a lot of vibration. Try though I might, I can't get the tail pipes centered in the rear valance bezels (too low). The pipes fit under the chassis very well with maximum ground clearance so I leave well enough alone. My other issue with the mufflers is they are too wimpy sounding, specially for a SHP engine.

Stu Fox

[Paul O.]

Re: Exhaust System Replacement

Grant the Gardner systems I have judged the front pipes generally receive a 40% deduct. Finish and date the config is fine.

The rear pipes a 60% deduct config, finish and date.

The mufflers 60% config, finish and date.

The pipes and mufflers are aluminized the rear pipes are not flatted correctly unless they have upgraded their processes and at the muffler the owner has to weld them. Which causes 2 welds at the muffler inlet.

The body seams on the mufflers and the end caps are not typical production finish shape and both body seams were pointing outboard not inboard as from GM or Walker.

Gardner systems are very good but they are not there yet. After owning and judging many original systems over the years. There are many areas that I personal pick up on during judging that I try to pass on to less experienced judges to help them during judging. Plus transfer that knowledge to the owner also.

As far as condition if a system has slight rusting ( not pitted) I personally would not deduct any points. I would expect some surface rust on a newly delivered car. That is the standard we had at the last 4 nationals and all the Regionals were I judged in the past years. Many owners question our call but after explaining the reasons for the deductions they understand the difference between an original and a replacement system.

Paul 18046

[Dan D.]

Re: Exhaust System Replacement

Let add something about the Corvette Central exhaust offering. Last year I purchased a complete carbon steel system from CC for my 57. The car was not yet ready for exhaust, so when I got it I fondled every piece for possible problems. I found some good ones. First, CC says they make their own systems, but the pipes all had paper ident wrappings that indicated they were made by a Canadian company. But the real issue was the clamps and hangers. One reason for choosing CC was the fact that their clamps were fine thread like the originals. While they were 5/16-24, they were very crudely made. The 'U's were not formed exactly 180* and would not fit in the holes in the formed part of the clamp. Fixed this by re-bending in a vice. The holes in the formed part (don't know the proper terminology for this) were not drilled in the center between the bends. The holes were actually partly in the bend radius, enough that the 'U' would not pass through the holes. Fixed this by filing the holes to fit.
I recently installed the system, and I don't need to tell you I had some real reservations about how well the pipes were going to fit. But the pipes did go together well and the bends, etc were all correct and the system installed fine. I did have to file a couple of holes in the hangers, but not serious. I pre-painted everything high temp black, including the clamps. Some paint has scraped off as the paint will not achieve full hardness until heated.
So bottom line is the CC system will work and actually looks good and goes together good, but check everything first and pre-fit. In this day and age I cannot believe that holes and bends in U clamps cannot be made with closer tolerances than these were. -Dan-

[Gene M.]

Re: Exhaust System Replacement

Dan,
Welcome to the world of reproduction (junk) parts. It seems everything even the most simple part needs rework before it fits.

Exhaust parts is difficult at best to find usable originals.

KEEP THE FILES AND/OR DIE GRINDER HANDY ON THE WORK BENCH............

[Harry S.]

Re: Exhaust System Replacement

Fred, I read the thread quickly so I may have missed this.

As I recall the 63 exhaust system was unique. The front pipe fit over the rear pipe. So if not properly installed an exhaust leak will occur. From 64 and up the front pipe fit inside the rear pipe.

Just another 63 anomaly!

[Stuart F.]

Re: Exhaust System Replacement

Harry;

Are you speaking about both the 2" and 2-1/2" systems?? I don't recall my 2-1/2" system fit that way on the 63.

Stu Fox

[William C.]

Re: Exhaust System Replacement

Yes, original '63 systems both 2 inch and 2 1/2 inch were a unique configuration at the joint under the trans. As was the 63-only center support.

[Terry B.]

Re: Exhaust System Replacement

I would certainly shop around and get pictures of the complete exhaust system before I made my selection. Talk to master level Chassis Judges such as Paul Oslansky and others to see the down side of each system. Another supplier to consider is Allen's Exhaust Systems at http://www.allencorvetteexhaustsystems.com/ I have not heard of a system that is completely correct. You have to balance cost and point loss I would guess. Good luck on the search.

[Frederick W.]

Re: Exhaust System Replacement

Thanks for all the help.
The topic is, as usual, more complicated than I expected it to be.

Apparently, none of the repro exhaust systems are completely original in configuration. I remain unsure as to which is closest:
CC, Gardners or Allen?
Which would get the biggest/smallest deductions?

[Paul O.]

Re: Exhaust System Replacement

Frederick I can only comment on 68-72 systems that I judge on a regular basis. The various suppliers for replacement systems that is all of them would on average sustain a 50% or greater deduction. For a 63 you need judges that do those cars would be your best help. Below is the process we judges should use to determine the correct deductions if any are due.

1. Configuration if different 20% deduct.
2. If config or finish not correct Date 20% deduct
3. Finish if Aluminized or some other type not used on originals 20% Stainless Steel 50% standard deduct plus other deductions for issues that differ from original systems this could reach 90%.
4. Complete if all items are there full credit.
5. Installation if correctly installed full credit.

If you use the process above and educate you self to what an original system looks like you then can make the best judgment on what system and from whom to purchase from. Hope this helps.

Paul 18046