Joel VanderKwaak <kwaak@PANGEA.STANFORD.EDU> wrote:

My question to you wise folks is this: what sort of performance gain, if
any, might I expect from replacing the stock exhaust system with
something 'better' (e.g. S&S headers, free flow muffler,....). I'm
looking to increase mileage and, if possible, gain a bit of power.

I installed the S&S headers, a DynoMax Turbo muffler, 1.25 ratio rocker arms and K&N air filter a couple of years ago on a perfectly functioning '87 camper and am satisfied with the result. I can't claim any numbers since I haven't ever dynotested the van, but it seems to keep speed longer in headwinds and up grades, though I don't see many grades worth bragging about here in Florida.
If you need a new exhaust system, I would look into the S&S pipes with the silver coating, mine are holding up well. The Dynomax muffler isn't any louder than stock but it is less expensive. I wouldn't install the ratio rocker arms again, my oil consumption increased from using none between oil changes to using a quart every 2000 miles. The K&N air filter will save you the cost of replacing your air filter again, but it will take a lot of miles to get a pay back on it.

I guess what I would say is that if you need to replace a component, consider the performance parts, but replacing good parts with them isn't going to be worth it. My fuel mileage didn't change after I added the parts, so there really is no payback on them.

Good luck,

TJ Hannink
Goldibox - 1987 Vanagon Camper, Wolfsburg Edition
Winter Park, Florida
http://home.earthlink.net/~tjhannink/
http://groups.yahoo.com/group/wolfsburg_campers
http://photos.yahoo.com/tjhannink [Vanagon] Album

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