chugging at 2500rpm

[rick2443]

my '70 911e is strugelling/chugging at 1500 to 2500 rpms at low power and hot, when I floor it it takes off, but doesn't want to go easy, from what I've read in this forum I think it's maybe too lean, when cold and warming up it behaves nicely. Any thoughts? have a recent tune up, valve adjustment. thanks, Rick.

[BoxsterGT]

Doubt if the "tune-up" included a proper adjustment of the MFI when under load.

It appears you have a lean condition midrange.

Len

[rick2443]

Thanks for the reply Len. Is that something I can do incrementally? For some reason I can't down load the "Adjusting MFI" from the technical articles. thanks, Rick.

[356RS]

Rick, Did this problem just start happening? What is the history of the car? Driven weekly or only once in a while? If the car is driven often and gets a good exercise the MFI pump rarely just goes lean in one area. Things are quite different if the car is stored for years.

[HarryD]

Something to consider.

Early 911 engines do NOT like being lugged. Anything under 2,500-3,000 rpm puts undue stress on your motor. It is best to keep it above 3,000 rpm at all times. In my opinion, they do not "come on cam" until 4,500+ rpm.