70 Corvette 2 1/2" welded pipes

[Patrick H.]

Re: 70 Corvette 2 1/2" welded pipes

I would agree with Gene - buy the whole system from CC and call it good.

I just played with a 2 1/2 in system yesterday on a 1971 LT-1, and did not note any issues.

[Joe L.]

Re: 70 Corvette 2 1/2" welded pipes

I would agree with Gene - buy the whole system from CC and call it good.

I just played with a 2 1/2 in system yesterday on a 1971 LT-1, and did not note any issues.

Patrick------

Well, I might just try the Corvette Central aluminized pipes after the problems I've had with the Allen's stainless steel pipes. I just can't get the Allen's left side pipes to fit right even after having them adjust them and even after buying a pipe bender to adjust them myself.

However, I'm certainly not going to use a complete CC pipe/muffler assemblies. I have enough NOS GM mufflers to last me for about 200 years and I definitely want to use them. I have NOS GM pipes, too, but I don't want to use them since I hate rust and they'll be rusty in no time.

Why do I want to use the GM mufflers? Nothings sounds like original GM mufflers------NOTHING!

[Patrick B.]

Re: 70 Corvette 2 1/2" welded pipes

Patrick -- Thanks for the good feedback on the 71 LT-1. The aluminized welded CC system sounds like the way to go.
Joe-- You are right about the real GM mufflers. My original 70 LT-1 mufflers sounded great with the 350/370, and they were also ideal with the present street tuned ZL-1 427. The rust however drove me to the Allen's stainless. I don't think Allen's even sold mufflers when I got these pipes. They only had pipes laid out on the ground at Carlisle that day.

[Joe L.]

Re: 70 Corvette 2 1/2" welded pipes

Patrick -- Thanks for the good feedback on the 71 LT-1. The aluminized welded CC system sounds like the way to go.
Joe-- You are right about the real GM mufflers. My original 70 LT-1 mufflers sounded great with the 350/370, and they were also ideal with the present street tuned ZL-1 427. The rust however drove me to the Allen's stainless. I don't think Allen's even sold mufflers when I got these pipes. They only had pipes laid out on the ground at Carlisle that day.

Patrick-----


Allen's eventually made mufflers, too, and I expect still does. However, upon my inquiry they once advised that the internal construction was not the same as GM mufflers.

I'm hopeful that the CC aluminized pipes will provide long-term rust prevention.

[Patrick H.]

Re: 70 Corvette 2 1/2" welded pipes

Why do I want to use the GM mufflers? Nothings sounds like original GM mufflers------NOTHING!

I'm hopeful that the CC aluminized pipes will provide long-term rust prevention.

So far, after 15+ years, the CC system on my 72 still looks good.

And, regarding the mufflers...there is a reasonable chance that some are in development.

[Joe L.]

Re: 70 Corvette 2 1/2" welded pipes

And, regarding the mufflers...there is a reasonable chance that some are in development.

Patrick-----

I've heard this several times previously but, so far, no one has come through.

[Patrick H.]

Re: 70 Corvette 2 1/2" welded pipes

Patrick-----

I've heard this several times previously but, so far, no one has come through.

New project.

[Patrick B.]

Re: 70 Corvette 2 1/2" welded pipes

Just to follow up: I got the Corvette Central welded aluminized 2 1/2 pipe/muffler combo. I finally got around to installing them, and they fit really well. No coat hanger wire necessary, and the exhaust extensions fit the body bezels for the first time since my original pipes. Thanks for the recomendations.

[Mike M.]

Re: 70 Corvette 2 1/2" welded pipes

i too have had excellent results with corvette centrals c-2 exhaust systems. the shipping charges were rather high. not CC's fault tho. mike

[Tom P.]

Re: 70 Corvette 2 1/2" welded pipes

Last year I needed a special, one of a kind 2 1/2in exhaust system for my son's 73 which had it's original (VERY tired) L48 350/T400. No such animal has ever existed.
We installed a built, roller cam SB400 and wanted to go with a FULL 2 1/2in system (manifolds to tail tips), with off road mufflers. The 63-65 2 1/2in FRONT pipe will not work, because they are not formed to go around a T400. I had an in depth discussion with a CC tech guy (forget his name) and he fully understood what I wanted to do and said there was no such ex system like we wanted. SOOOOOOOOOOOOOOO, I ordered a full 72 2 1/2in system with off road mufflers (such as what would be on an LT1/L82 car). I never fully understood why he recommended a 72 system rather than a 73 system??? BUUUUUUUUUUT, the forward end of the ex pipe which attaches to the manifold is 2in and then goes up to 2 1/2in back to the mufflers. Each side of the system is only 2 pieces, plus the tips.
When the pipes arrived, I took the two front pipes to a muffler guy that I've been using for about 35yrs. He cut off the 2in end, fabricated and welded on a 2 1/2 end to fit the 2 1/2in ex manifolds. I had a Z28/LT1 style intake and Holley in the attic plus a pair of re-finished valve covers. When built, it VERY CLOSELY resembled a 70-72 LT1 engine. VERY minor modifications were done, such as fabricating a fuel line for the Holley.
Bottom line--------------our mildly modified front pipes and the remainder of the ex system fit like it was installed in St. Louis!!!!!!!
It ain't correct, but it looks as if Chevy did it.

[Paul D.]

Re: 70 Corvette 2 1/2" welded pipes

Tom, I would like to do exactly what you did on my 71 SB 4spd car. Were you told that the 65 4spd front pipes would work had your car been a 4spd car? I could not tell if the CC pipes were "flattened" where they pass under the rear differential from your picture. Do you feel you still have sufficient clearance with stock sized tires? Just FYI, 73 used a different muffler and extension than the 70-72. The off road muffler they offer is the 68 which I think works with the 70-72 extension. That is probably why they told you to order the 72 system.

[Tom P.]

Re: 70 Corvette 2 1/2" welded pipes

Paul,
IT IS MY UNDERSTANDING, that if my son's 73 was a 4sp car, then 63-65 style 2 1/2in FRONT pipes could have been used. But I was not going to go out and buy a pair just to find out.
I checked on using 63-65 front pipes with everyone I knew would PROBABLY be knowledgeable-----------------it was unanimous that they would work for a 66-later 4sp car, but not for an auto tranny car.
Thus, after LOTS and LOTS of assessing of all the pipe configurations, I concluded that the way I went above was the only acceptable option---------------------AND IT WORKED GREAT!!!!
Now, with all that said, I feel I had a major advantage (having the 2in piece cut off and a 2 1/2in piece fabricated and welded), because I have been using a muffler guy that is an absolute genious at bending and fabricating MANY, MANY ex configurations.

Just one example. There is not, and never has been (factory or aftermarket) a FULL 2 1/2in ex system for a 55-62 Corvette. I'm talking manifold to tail pipe tip. My muffler guy fabricated a manifold to tip 2 1/2in system (although, 2 1/2in will not go through a 56-7 bezel, so he fabricated 2 1/2in 61-2 style tail pipes).

[Mark E.]

Re: 70 Corvette 2 1/2" welded pipes

i too have had excellent results with corvette centrals c-2 exhaust systems. the shipping charges were rather high. not CC's fault tho. mike

Right now, CC is running a free shipping special on exhaust systems.

[Paul Y.]

Re: 70 Corvette 2 1/2" welded pipes

Gene, I agree. I have Allen's welded 2.5 inch on my 71 and found them to fit with just a little tweak or two. Then when I put the LT-1 block in for grins, I put 2.5 midyear exhaust manifolds and header pipes from a mid year. Not too bad a fit that way either. I used Allen's on my 63 also years ago but they were not the welded set. They fit pretty well also.

[James G.]

Re: 70 Corvette 2 1/2" welded pipes

I have been debating what to do with my 71 LT1 for the exhaust...

I was wondering about buying the midyear 2-1/2 inch head pipes and having them swaged down to 2" like the originals, using original BB midpipes with the creases and running NOS mufflers, welding the mid pipes and mufflers.... but it is going to cost somewhere around $2,000 to do it like this... would I lose points with a system like this?

AM I better off buying the 2-1/2 CC welded system?
OR the Gardner system...
Last gardner I bought was for a 69 Z28 and it was $2,000 so if I could do an original vette system for the same I considered it a good deal.

FWIW I have ordered the judging guide and everything else NCRS has for the 1971 year model...