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-   -   rev buzzer and rev limiter? red line? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/rev-buzzer-rev-limiter-red-line-63171/)

inittab 03-19-02 06:15 AM

rev buzzer and rev limiter? red line?
 
Hey All!

I found my rev buzzer at around 7k rpm. In fact, I've been using it as my upshift indicator. heheh ;) I'm wondering... does my 85 GS also have a limiter somewhere up higher? My 76 Cosmo had a limiter but no buzzer. Also, what exactly is the red line of the stock 12a rotary. 7k or 8k? How high can a rebuilt balanced 12a rev? I've heard rumors of 10k+, is this true?
TIA

WackyRotary 03-19-02 08:03 AM

I disconnected my overrev buzzer a long time ago. IT is just too annoying. Bridgeports spend more time in the dreaded noise range. Its rather simple to disconnect if you know how to remove the steering wheel, turning signal cluster, and then the insturment panel. Its just a long tiny screw that needs to be disconnected.

Red line in a rotary is were ever the best shift point is in first gear in my opinion. But a stock 12a is very close to 6700-7200rpm so you won't be in the buzzer much anyway.

peejay 03-19-02 08:24 AM

Aye... if you wait for the redline buzzer on a stock 12A, you're shifting too late.

I don't think there is a rev limiter...

Never take a stock 12A over 8500 for any length of time, or the apex seals will self-destruct. Not a good idea to stay over 6200 for very long, but it's "doable". It just reduces the engine's lifespan.

With race apex seals, race bearings and stationary gears, upgraded oiling system, etc., a good limit is 10,500, but engine life is greatly dependent on the RPMs you use. The higher you rev it and the more often you go there, the lower the engine life... generally you need a rebuild every 40 to SIX race hours... but that's still loads better than a comparable piston engine.

yayarx7 03-19-02 10:35 AM

NO rev limiter, I have overeved most of my 12a's at one time or another.

79+80_rx-7 03-19-02 03:47 PM

I have reved my stock motor up to 7800 RPM before, but couldnt get any higher. When driving I couldnt pull it over 6000RPM in any gear unless I downshifted and popped the clutch (it was an accident, pulled to hard towards me, missed third, and went into first :D) oh well, LATERZ,
Andrew

SilverRocket 03-19-02 03:49 PM

Couldn't pull it over 6k? Your car sounds all fuxed up:eek:

eddierotary 03-19-02 04:39 PM

i dont like to pass the engine over 6k i dont wanna blow it.

NOTA V6 03-19-02 05:06 PM

http://www.monmouth.com/%7Erothe/overrev.html

Set the shift buzzer anywhere you want it. Keep your eyes on the road, your hand upon the wheel. The future's uncertain and the end is always near. ;)

Seriously, drag racers pay extra to install a shift light. The buzzer is even better. :)

inittab 03-19-02 06:16 PM


Originally posted by NOTA V6
http://www.monmouth.com/%7Erothe/overrev.html

Nice tip!!!! This looks like a good weekend project to me. I'll take peejay's advise and set it to go off at around 6200. Cool!

Sterling 03-19-02 10:56 PM

I have a home-made electric exhaust dump that I made from an aluminum Dodge throttle body. Everything else is milled off the outside, so it's essentially just a short piece of tube with a butterfly valve in it. It's simply teed to the exhaust collector just befor the muffler. Works really great.
It's acctuated by a heater core vent damper motor which uses a radial switch to turn itself off after it rotates 180 degrees. That is mounted in the back in the storage area next to the battery. There is a bicycle brake cable running from it through a hole in the floor and to the spring loaded butterfly valve.
The switch is an old headlight pop-up rockrer switch, and occupies the space where there was a dummy plate.

It's worked great since this summer when I installed it.

But now I've taken it one step further. I've done away with the over-rev buzzer, and will be wiring the leads I've installed to a relay that will operate the motor instead of the rocker switch.

I've removed the trim potentiometer from the tach board, and run lines from it as well. They will end up at a larger 10K ohm pot mounted in the dash board.

The result will be that the exhaust will open up completely at whatever RPM I set it to!


Other uses for this circuit include:
Nitrous,
Oil road spray using an old windshield fluid bottle,
Neon lime green spray paint mister,
Spark plug in exhaust,
Brake lights,
(Or shuts off the tail lights at night)
Flamethrower,
50 watt halogen light aimed out the hatch,
Neon sign in hatch that says, "SEEYA!",
Bazooka.

Did I miss anything?
:p:

nipplebandit45 03-20-02 08:54 AM

WTF!!! Sterling yo got o much spare time on your hands.


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