I ordered two stock head pipes from Year One for my 65 Olds restoration wherein the engine is a 425 block with the W-manifolds. The pipes came but when attached to the manifolds they were not equal in length. I had to have two or three inches added to the drivers side muffler. My OCA 65 advisor told me they should be the same length, the assembly manual seems to show them the same length and the mufflers are the same length and so are the tail pipes which a duplicates of the originals. Therefore I conclude that my advisor is correct. I sent Year One a photo of the headpipes installed along with an email explaining the situation. The email was non-adversarial. I never received a response from them. The only responses I did receive were pre-Christmas email ads to buy more parts. I spent about $20, and two hours of drive time to take the driver side muffler to the shop to have some pipe put on so I could install the pipes. Just the facts.

 

Any muffler shop has the flange or bring your old one in and they cut and bend it to what you need.

 

That is what I did. They added a piece and the proper section flared and the whole system is on and good. It took some time and fiddling to get the tailpipes where that had to be. While I'm at it there are two things I did to make sure they would not move. One is that the assembly manual shows only one muffler clamp on the rear of the muffler that is Incorporated into the hanger. I used one more on each side because it holds the pipe better so it can't twist thereby causing the tailpipe to shift it's place in relation to the rear bumper. The second thing it did was once the tailpipes were adjusted I put a "security screw" into each of the hangers that are attached to the frame. They also help control where the pipes will be. The rubber part, although secured by the big rivet can move over time allowing the pipe to settle. But with the security screw going through the rubber into the metal part it will be better secured.