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AFM744 AFM744 is offline
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Join Date: Dec 2001
Location: Campbell, CA
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Originally Posted by diverdan View Post
Thanks for the advice. AFM, does that mean I can use a WUR from an old M-B or a BMW and just reset the control pressure? That would be a real cheap fix until I realize that maybe somebody did me a favor and upgrade to the unwired product.

Most important objective with the WUR is operating temp (hot) control pressure. Cold CP is less crucial IMHO because we shouldn't be lead-footing it or boosting it when it's cold anyway. I actually removed my bimetallics and have no cold CP enrichment, just the 7th injector. The WUR needs to have a manifold pressure enrichment. I don't know whether this is universal across all Jetronic WURs. Furthermore, the spring preload and diaphram travel of this manifold pressure is crucial. You can cross-reference the CP delta from -1b -> +1b manifold absolute pressure on our WUR to the WUR specs on other cars... but the more I think about this the more doubtful I get. I don't remember whether my Mk1 Rabbit or Mk2 GLi WURs had manifold pressure enrichments. I'm betting a WUR from a Saab 900 Turbo would, but god knows what it's enrichment characteristics are.
So I stand correcting myself, can't just use any ol' WUR. I'd instead go after the shop!!!
X-1, AFM744, Jon, '92 C2 Turbo
JE 8:1 pistons, 964 cams, 38mm intakes ported/polished/twinplugged, ARP hardware, B&B headers/exhaust, 355whp. Full-blown GT35R 3.2 intake EFI pending...
Where my misspent time and money is currently going.
Old 10-28-2008, 07:19 AM
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