450SL cuts off 3500 rpm and trans slips 5000 rpm

[Bondavi]

My SL has always bogged or missed after 3500 RPM. Anything before this, it runs and pulls smoothly. Trans does not slip at all.

However today when I held the trans in 1st gear, after 5000 RPM the trans would "let go" and the engine would free rev to redline.

Is there some sort of module vacuum or electronic that is erratic that could be causing this?

Thanks in advance!

[Bondavi]

Got no help form anyone on here, but to post the fix, I adjusted the timing to TDC with vacuum disconnected and the bog at 3500 rpm went away. Car pulls cleanly and with a lot more zing.