320i doing 8000rpm at 110mph still no redline = somethings not right.

[Jaxx]

If you keep going at 120mph its doing 20mpg rpm, then stops in the 6 o'cock position at any speed above. (on a private road of course)

I take it the standard 1989 6cyc 320 did not in fact come equipped with infinite revs, everything is stock, including wheels with factory profile rubber (15in bbs). I believe it has the 4.1 non slipper diff. I found a online rev calculator for a 318is but not for a 320 so I dont know what it should be doing with the current setup anyway.

I am not brave enough to try and hold it long enough to see when the rev cut kicks in, my friends older 325 didn't seem to have one and blew itself up when he tried, so any ideas about where to start looking at this problem? I am going to take the cluster apart to inspect the batteries as I understand that's a common complaint, but does anyone know of other tach problem areas? Or can some other 320 owners tell me whats usual at say 70?

Thanks in advance for any suggestions.

[SamE30e]

That's like 7500, chances are it's chipped with a rev limit of 7750.

[SpecM]

holy crap... what's it sound like up there?

[bignate948]

thats crazy

[Farbin Kaiber]

Sounds like impending busted rocker territory.

[mark247]

m20b20 rev out to 10000rpm no problem

[kamotors]

m20b20 rev out to 10000rpm no problem

hmmmm, doesn't sound safe

[E30_pilot]

hmmmm, doesn't sound safe

waffleswaffleswaffleswaffleswaffles.

and to PO theres probably a chip in it as stated by SamE30e

[jlevie]

Might it be that someone swapped in a cluster that has the coding plug for a 4 cylinder motor. That will make the tach read high by a factor of 6/4.

[Charlie]

That's like 7500, chances are it's chipped with a rev limit of 7750.

Yea, no.

7-7.2k and you're gonna have stock rocker arms spewing all over the place.

Might it be that someone swapped in a cluster that has the coding plug for a 4 cylinder motor. That will make the tach read high by a factor of 6/4.

Aaand we have the real answer.

-Charlie

[Jaxx]

I never thought about a chip and I'm pretty sure its not, everything else is unmolested.

Might it be that someone swapped in a cluster that has the coding plug for a 4 cylinder motor. That will make the tach read high by a factor of 6/4.

I'll take a look for this, I'm going to try and borrow one of the tachs you clamp on the ht lead and see how far is out before I start pulling things apart. Thanks for the suggestions.

[Todd Black 88]

8000rpm in an M20? For all of about 1 second.

"Might it be that someone swapped in a cluster that has the coding plug for a 4 cylinder motor. That will make the tach read high by a factor of 6/4. "

I agree, this is probably the truth.

[Jesse30]

m20b20 rev out to 10000rpm no problem

wat? it would eat itself..

[SpecM]

m20b20 rev out to 10000rpm no problem

the head would explode like a b25's would

[e30nub]

link me to 318is rev calculator