Rev limiter options

[Huw Powell]

> The rotor works with older cars where the revlimiter was built into the
> rotor.

Cool, I didn't know that...

> Mike, on your car, the revlimiter is controlled by the fuel pump
> relay, it takes an rpm signal, and at the right point, shuts off fuel.  You
> could try snipping this signal wire, but that may affect other operations,
> especially fuel shut off in the even of an accident, etc.

snipping the coil signal will simply keep the fuel pump relay from
turning on...

> Never really tried
> it, of course, if you were willing to risk it, you could just rewire the fuel
> pump with your own relay and bypass that end all together, but then you
> wouldn't have a revlimiter at all.

the trouble with that is you lose two safety features, one is of course
as you mention, fuel shut off in case of accident, and the other is
losing any rev limiting at all.

>  There may be a way to modify the signal
> to read 10% low, that would probably do the trick, not sure exactly how it
> could be done though.

probably a nightmare... one thing that *might* work, sort of, would be a
fuel pump relay from a 6 cylinder car running a similar system (old
volvo/saab/beemer?).  Much in the way a 4 cyl relay will give you a 4/5
* 6500 = 5200 limit, a 6 cyl relay should create a 6/5 * 6500 = 7800
limit.  A bit high, I suppose, but it's something.

A side note, as far as I know, my 90Q does not have a functioning rev
limiter (!).  I've been to 7k with it a couple of times and I'm not
going to push it further.  Another note, the rev limiter seems to vary
slightly from 6500 between relays, from what I recall.  But not enough
to be "useful"

> Of course, if you have EFI, a nice soft touch rev limiter is an option, as
> opposed to the on-off CIS revlimit.

Of course, Javad, of course :)

--
Huw Powell

http://www.humanspeakers.com/

http://www.humanthoughts.org/