67 BB Side Pipe Part Numbers

[Ronald L.]

Re: 67 BB Side Pipe Part Numbers

My styling eye never did like the shallow created by the flat rockers that followed the tapering lines below the break line of the C2. The convex cover fills that in nicely.

[John H.]

Re: 67 BB Side Pipe Part Numbers

These pipes of mine are smooth with two exceptions; one is a single wrinkle on the passenger side (thumbnail), the other is a mandrel-type "flat" on the driver side where the pipe crosses under the frame [IMO, to add clearance]. Other than that --- nada ! So they must have perfected a bending method that minimized deformations at that time.

Wayne -

Mandrel-bent pipes are absolutely smooth and round, with no change in inside diameter at any point; that's achieved by pulling the round mandrel die through the pipe while it's being bent, which is no mean feat. External-die pipe benders today are much more sophisticated than they were in the 60's, especially those that are CNC-controlled, and they create fewer (and smaller) inside radius "wrinkles".

[David S.]

Re: 67 BB Side Pipe Part Numbers

I think I answered my own question. I was looking at a friends 66 L72 (vin 9xxx) that is completely unrestored. It is an unmolested all original survivor. I got under the car to look at the side pipes and sure enough the pipes have wrinkles exactly how the picture I posted looks. There is no evidence of the pipes being removed from the car either.

As for the 66 Judging Manual, it says the pipes were mandrel bent and should not have wrinkles. Granted there are odd parts on these old cars and several variations, I would be upset if a judge ruled "wrinkled' side pipes as incorrect.

-Dave

[John H.]

Re: 67 BB Side Pipe Part Numbers

As for the 66 Judging Manual, it says the pipes were mandrel bent and should not have wrinkles. Granted there are odd parts on these old cars and several variations, I would be upset if a judge ruled "wrinkled' side pipes as incorrect.

-Dave

Dave -

That's because most folks don't know what "mandrel-bent" really means or how the manufacturing process is controlled; they see the term over-used in the hot-rod magazines for things like expensive custom-built headers and exhaust systems, and the next thing you know, Corvette exhaust pipes are described as "mandrel-bent". That's another "urban legend" that will have to be beaten down through education until the term is eliminated the next time the JG is revised.