911T - better with rev limiter?

RobFrost · Post by **RobFrost** » Sun Sep 19, 2021 8:45 pm

I've just bought a 6,500rpm rev limiting distributor rotor for my 1979 2.2 litre 911T. Thinking was, it gives me a clear notification of overzealous driving, as well as protection against mechanical gremlins such as stuck throttle etc. But I heard they can be hard on crankshafts. Of course, the intention is to fit it and never to use it. Is the engine better protected with the rotor, or without? I appreciate this is to some degree a matter of opinion.

911hillclimber · Post by **911hillclimber** » Sun Sep 19, 2021 9:04 pm

I have 2 911 engines, both protected by this rotor arm design.
Imho fit it, never drive the engine without one or some such device.
Easy to hit those rpm.

Jonny Hart · Post by **Jonny Hart** » Mon Sep 20, 2021 7:57 am

The mechanical limiter is horrible unless you like whiplash. Also not great for the engine as the fuel is still pouring into the cylinders unburnt.

Decided to address this in our CDI+. It has two electronic limiters. One retards the ignition. You feel this as the car slightly loses power which gives you a prompt to change up. If you drive through that, the next one is a cyclic ignition cut rather than a full cut. You can drive full throttle on this without being slung through the windscreen.

jb · Post by jb » Mon Sep 20, 2021 9:37 am

The limiter on the CDI+ works extremely well with just enough power loss to make it obvious that you have gone over the limit.

RobFrost · Post by **RobFrost** » Mon Sep 20, 2021 9:39 am

Jonny Hart wrote:The mechanical limiter is horrible unless you like whiplash. Also not great for the engine as the fuel is still pouring into the cylinders unburnt.

Decided to address this in our CDI+. It has two electronic limiters. One retards the ignition. You feel this as the car slightly loses power which gives you a prompt to change up. If you drive through that, the next one is a cyclic ignition cut rather than a full cut. You can drive full throttle on this without being slung through the windscreen.

In a way, horrible is good - it'll teach me not to do it! But great to know there's another option.

jwhillracer · Post by **jwhillracer** » Mon Sep 20, 2021 12:06 pm

Yes, the limiter is there as a safety device, not to tell you it’s time to change gear!

JW

911hillclimber · Post by **911hillclimber** » Mon Sep 20, 2021 3:09 pm

Yes, too true.
I just hit it every now and then when I 'miss hear' the engine scream through my helmet.
Won't have the problem next year.

gridgway · Post by **gridgway** » Tue Sep 21, 2021 8:23 am

Going OT, but do you run any kind of shift lights on your race car Graham?

DDK - Die Deutschen Klassiker

911T - better with rev limiter?

911T - better with rev limiter?

Re: 911T - better with rev limiter?

Re: 911T - better with rev limiter?

Re: 911T - better with rev limiter?

Re: 911T - better with rev limiter?

Re: 911T - better with rev limiter?

Re: 911T - better with rev limiter?

Re: 911T - better with rev limiter?