Exhaust system
You'll need someone to make the front pipes fit your headers of course.
M
The Magnaflow system is nice but pricey and the although the mufflers is 2.5" through the body...the damn outlet is 2" for the stock tips......This can be easily rectified by cutting the 2" part off the outlet and fabbing a new short 2.5" piece and enlarging the tip inlet. A member here (ChrisHewitt I think) did this to his slightly modified L-71 427 car.....worked and sounded great....
Short of that....just about anything else out there will be a restriction.......barely enough for a 400hp car.....if you have a real cam in there it will just kill it.....
Jebby
OP, I do not wish to hijack your thread, but one quick question - Your Muncie is damn clean as they get. I've spent hours and hours on mine with various brushes, Orange de-greaser, water, etc and still can't get it looking that good. Looks like you may have painted it - Wheel paint?

The Best of Corvette for Corvette Enthusiasts

You look pretty handy, do you weld? If so you can build your own custom exhaust fairly easy. I built this exhaust above using Summit's basic stainless pipe set and FlowX mufflers.
In addition, with custom exhaust, you can build your system without all the factory kinks. Also, using band clamps is really helpful if you need to remove your exhaust system easily. I found that I have been routinely removing mine to gain access to the rear axle for suspension work.
Last edited by wolfk; Mar 25, 2023 at 11:24 AM.
For clarification...and possibly the reason...my AFR heads have raised exhaust ports.....but we are talking 1/8 inch raised......I don't believe that is enough to justify how far off these systems were. And I measured and checked my frame with body off....it was straight and square.
All the companies make excuses that 70's Corvettes had huge factory tolerances in manufacturing....and thats why the exhaust doesn't fit. My response...BULLSHIT. No way that the frames are off by the 2-3 inches off these pipe were from properly fitting through the crossmember holes.
Another telltale sign of a badly designed exhaust is related to the fact the engines in C3 Corvettes are offset by an inch to the right......so by design, the pipe bends behind the differential MUST be designed to accomodate that. The left side angle bends and lengths have to be longer on the left side than the right side. StainlessWorks bends are exactly the same on left and right.....so its screwed up from the start.
I fought with them about it, and all they did was tell me they have sold hundreds of these without fit complaints.....again. BULLSHIT.
On my 69 Convertible project,.....I am done with all this "upgrade" nonsense, including headers. I am using factory exhaust manifolds and probably the Corvette Central system so many have said fits well on a stock car. They are NOT mandral bent.....instead factory squish bends. I don't care. Done with the nonsense. All this stuff about headers is fine for a race car. I have headers on my 408 SBC....but it came with the problems and excess cost mentioned above. My VortecPro 468 big block with be using a QUadrajet carb, factory hi-rise intake, and factory cast exhaust manifolds.....and into 2-1/2 full squish bend exhaust. If its "choking" the engine, so be it. Sick of the nonsense.
For the wannabee racer types that proclaim headers are a must.......my response is that the difference in performance is measured at the top end of the RPM scale....where only people driving crazy on the streets will ever experience. The EngineMasters episode with the continously dented headers proved to me that its all nonsense in the RPM ranges we actually, or that I actually, drive on the streets. Its all great marketing that too many, including me, fall for. In a race, on a track...yeah...it matters, Otherwise....one word....NONSENSE.
Last edited by Shovels and Vettes; Mar 25, 2023 at 12:12 PM.
I read all the threads about the expensive systems not fitting, and guys spending hours on trying to make it fit. The guys dissing the 3" custom systems, and the guys loving them. The 2.5" vs the 3" inch, the 3" not fitting, the 3" fitting great.
I found a guy out in the country here, that alot of the classic car guys use, he's done quite a few C3's, some he said he had to "mash" (not sure if that was the word he used, but makes it 2 7/8's) the section going through the crossmember, some he didn't as the bend right there made it 2 7/8's). But he did 3" from my headers on to new Flowmasters 40's, and 3" tips for under $700, and I didn't have to touch it (I did get underneath while he had it on the lift to check it out, great work). He said having solid motor mounts helps, I should never have a problem.


















