Does anyone have this installed on there car. Would like to know what they think about it. Was there any improvement or not.

well i dont have a down pipe, but i noticed minor improvements with a highflow converter, also from what i remember i beleave there was high prase for the 3" down pipe

If you have a non supercharged motor you will probably lose some low end power but make more up top. If your supercharged the gains would be greater. I think for the cost of a 3" dp for the Bonnevilles it much more penny wise to get ported manis or headers; but if your looking to get some type of gain with least amount of $ you can spend I guess thats the route to go.

Ed

If you are supercharged, you are better off getting a DP before PEMs or headers. The stock DPs have a restriction in the neck where the DP attaches to the rear exhaust manifold. I ran PEMs with the stock DP and it caused problems (KR related).

ANyway, if you're interested, I did some concrete testing to prove that DPs work. Check the 1st and 9th posts in this thread:

http://www.bonnevilleclub.com/forum/...ht=dyno+proven

I have a 3" DP, 3" HF cat, and PEM'* on an otherwise stock 1995 L67 and I can say it is almost stronger than with the CAI, 2.55" SC pulley and full 3" exhaust.
It is definitely stronger than when I bought the car last summer, but then there has been a lot of maintenance done that had been neglected by the previous owner.