continued l-jet M20B23 troubles

[kronus]

roger, will try. pinging as in detonation, right?

[LJ851]

roger, will try. pinging as in detonation, right?

Correct.

I just did some research and saw some #s like you are talking about. Is your dist on this list ?

http://forums.bimmerforums.com/forum/showthread.php?836299-79-323i-M20B23-Timing-Specs&p=16931083#post16931083

The only reason i could imagine such a low advance # would be for emissions, not for performance at all.

[kronus]

I will approach it with the carbed-M10 approach to distributor tuning, i.e. advancing the piss out of it. However, if I'm advancing until the detonation point with just mech advance, wouldn't that put it solidly past that point with vacuum hooked back up?

[LJ851]

I was just thinking of a way to see if you can find your missing horsepower at full throttle. Yeah, it could still detonate at part throttle with vacuum hooked up and another potential drawback could be that you are moving the entire timing curve up so you are changing the timing at idle as well.

It might not be an issue or you may need a dist that has a longer advance curve (or you could modify yours)

[LJ851]

Any news?

[kronus]

yup! there is success!

Retimed it yesterday. Ended up giving it a lot more advance than it had, and now it's great, chirps 225s, accelerates up hills, etc. It's still not fast, but it's good now. Still runs hot, though, so I think either I have an air bubble, the radiator is done, or an HG leak pressurizing the coolant. The temp gauge and/or sender might also be going - it will be steady midway between middle and the mark to the right of it, and then randomly rise up to the mark and come back down without much of a change of engine load.

[LJ851]

I thought so. :up: