So a while back I fabricated my race exhaust (Straight pipe off header into an 18" resonator) for the GSR and I was told to use this tip that is not quite a downturn rather a mandrel bent pipe that was at about a 30 degree bend down to the earth. Last summer I was at Lime Rock for the cars maiden voyage and damn the car was vibrating so bad it was driving me crazy! I finally broke down and asked for a "real" downturn and I through it on the car today. Wow what a difference the car now idles without the car shaking, etc.

In my opinion, FYI out there buy the downturn. Perhaps I lost .5 hp becasue of it. I don't care I still can have my sanity!

 

Pics?

 

the turndown is cut parallel to the ground making an oval shaped opening? or, a regular 30* bend cut perpendicular to the tubing with a normal circular exit?

 

Here are the pics RJ requested and yes those are spider webs as I am broke and the car doesn't move near enough!






Picture 2 is the new downturn and Picture 4 is the old.

 

Don't forget too, that you can point the turndown away from sound control if your car is at risk of popping the sound limit.

 

I'll have to take pics of the one my brother made. It's closer to the design of your new one, but without sticking down a bunch like that one.

 

Instead of traditional crushing style muffler clamp, you can buy the several inch wide band style clamps to hold the turndown tip on and allow you to steer it away from the sound meter. You do need the OD of the end of the pipe and the end of the turndown to be the same so they butt up together for the band clamp and not fit one inside the other.

I'll be home in a few days and can post a pic if anyone is interested.