How to identify a Rev Limiter?

[jstein]

Hey gang - silly question, but important. How can I:

1) Tell if my '79 SC has a rev limiter?
2) Identify where it is?

Thanks

[jyl]

I'd think it does, they were stock AFAIK.
1) gradually apply throttle to increase revs to a little past the redline on the tach, if it doesn't get there then you have a rev limiter or you've been pulled over.
2) not sure on SC's - I think the distributor? Just a guess.

Edit: here's a thread that (further down) shows a rev limiting distributor rotor in an SC.
rotor rev limiter..

[jstein]

Does this imply that to eliminate the limiter one just replaces the rotor with a (non-sprung) version?

Would there be any real reason one would do that anyway?

[klaucke]

If you rebuilt your motor with a big bore kit, and a lighter valvetrain, and some other performance mods, etc, your engine could very well rev past the old redline safely, in which case it might be beneficial to elimate the stock rev limiter for track use.

[Early_S_Man]

USA SCs use a speed switch triggered by the same signal as the tach ... which cuts off the fuel pump when the limit is reached. It is is mounted near the tach behind the instrument panel.

ROW SCs use a rev-limiting distributor rotor.

[Joeaksa]

Have seen several cars that never should have had the rev limiting rotor on them, as well as seen standard "non-revlimiting" rotors on cars that needed them.

Before running the engine up anywhere near the redline to see if it has one, how about popping the distributor cap off and checking the rotor? A stock one looks... well, stock with no extras on it and is usually smaller than the other flavour.

The rev limitiing one has a number stamped on it, usually something like 5600 or 6000, meaning the rpm where it stops working. It also has a spring loaded device in the top of the rotor that moves out at higher rpm, makes contact and stopping the spark. Its usually also larger and very easy to tell the two apart once you have seen one.

If your car has one of these on it, pls make sure that the rpm is what the factory recommends. They pretty much all fit the same dizzy and if someone in the past may have changed it to something that is not what was recommended.

JoeA

[SpeedracerIndy]

For reference:
rev limiting rotor (from a euro SC):


Non-rev limiting rotor: