Chris,
I'm having the same problem with my engine: it just doesn't want to rev past 4,000rpm, under load.
My mechanic has tried everything: another MFI pump; another ignition system; another coil; another distributor; new spark plugs and new injectors.
No change.
He even performed a compression test -- 210 for every cylinder.
He's baffled, and he's got 40 years experience with Porsches. Before I had the distributor modified I had the Marchal alternator rebuilt and the voltage regulator replaced. My mechanic didn't check these components in the initial elimination round, but when I suggested it, he got excited as the only thing left to check is the valve timing, and he can't see how it could be that given the fact that it's behaving perfectly
under 4,000rpm ...
Matt Holcomb
MFIWDP
1974 911 Carrera 2.7 RoW
1975 Mercedes-Benz 280SE
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