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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
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Originally Posted by 911st View Post
If you can not achieve this with the stock WUR then you might be able to use an adustable WUR to get things closer. There might still be some comprises like being a bit too fat on first boost (in the 9's) so you can access the extra fuel available up top.
Keith, you're being too gentle! Personally I think I would assign the term "pig rich" to that (9 AFR) if running a stock setup. Unless of course a person is running higher than stock boost and near redline, then the super rich might be appropriate once you get to the upper echalons of things. Get in the high ten's to low eleven's and you'll be plenty safe most of the time and not sacrafice HP or wash your cylinder walls with excess gas. There are about a hundred zillion posts on this subject (many of which Keith has graciously authored and cataloged for posterity).

By the way Maxx, if you've been running with a 1.0 bar spring and the stock intercooler without knowing where your air-to-fuel ratio is, then definitely go back to the stock .8 bar spring until you can verify your state of tune. Your stock WUR is calibrated against the stock wastegate setup. Increasing boost beyond .8 bar requires either a larger IC to cool the air charge and guard against detonation, and/or modifying the AFR to provide a richer and cooler mixture.

Currently there are two main sources of adjustable WUR's: one custom modified by Brian Leaske, and the other entirely digital. The price difference is about double, so it all depends on how much flexibility a person wants in tuning.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 03-26-2010, 08:49 PM
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