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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,130
Quote:
Originally Posted by RarlyL8 View Post
Placing modified fuel heads on engines not requiring them has messed up a lot of folks. You cannot adjust out the overkill. From what I have seen, a 930 CIS engine needs to make around 375 WHP before the stock system begins to struggle to keep the top end from going above 12:1 or so. This of course must be verified with AFR readings as every engine and configuration are a bit different.
That is correct, hindsite is 20/20...

I do have new 964 cams, adjustable boost up to 1.2bar, BL adjustable WUR, B&B headers, Garretson long neck intercooler, freshly rebuilt K27HFS turbo, and LC-1/G3 gauge to see the AFR's... but as it turns out, from my experience that is not anywhere near enough to need a modified fuel head.
I wonder if I ported out the intake ports, injector blocks, and manifold to somewhere around 36-38mm, what difference that may make.

The digital WUR may be able to adjust out the overkill, but it would be raising the control pressure so high under boost to do it, that it would also be holding the air flow metering plate closed more than you want at full throttle to do it.. Overworking the turbo trying to suck in air in the process.

I'm currently running with the boost signal hose disconnected from the WUR too.

I havn't been doing any boosted runs yet since getting mine running again about a week ago because the cams, rockers, chains, sprockets, and turbo only have around 60 miles on them so far.
Old 10-31-2008, 04:26 PM
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