Aftermarket rev limiter
Discussion
I am looking at aftermarket rev limiters for a friend's rally car, a carburettor fed Corolla.
It has the factory electronically driven single coil and distributor.
There are several on the market (omex, lumenition, etc), and all claim to do the job, but I have heard anecdotal evidence that they can cause coil failure over time.
As the limiter appears to ground the coil when limiting, I assume the risk of damage comes from overheating the coil if holding revs on the limiter for a period of time. Is this plausible?
The owner just wants some protection from missed gearshift overrev, after bending some valves.
So : are they all useless, is one brand better than another, any experience of them?
It has the factory electronically driven single coil and distributor.
There are several on the market (omex, lumenition, etc), and all claim to do the job, but I have heard anecdotal evidence that they can cause coil failure over time.
As the limiter appears to ground the coil when limiting, I assume the risk of damage comes from overheating the coil if holding revs on the limiter for a period of time. Is this plausible?
The owner just wants some protection from missed gearshift overrev, after bending some valves.
So : are they all useless, is one brand better than another, any experience of them?
Considering that coil costs about £5 and a new engine >£1000 fit a the limiter! Yes you could potentially overheat the coil, but why are you sitting on the limiter for long periods? Chances are peoples coils who died would have died anyway, and they just chose to "blame" the limiter!
(the higher the revs you sit at, the hotter any coil will get, because it is having to transfer more energy to the plugs in any given time period)
(the higher the revs you sit at, the hotter any coil will get, because it is having to transfer more energy to the plugs in any given time period)
If he killed the engine from putting it in a wrong gear...no rev limiter is going to prevent that one.
But certainly having a rev limiter of some sort is better than nothing.
If it's a really old car with a dizzy, there used to be some rotor arms with a spring mech inside that would prevent spark at a certain rpm
But a separate adjustable unit will be handier.
But certainly having a rev limiter of some sort is better than nothing.
If it's a really old car with a dizzy, there used to be some rotor arms with a spring mech inside that would prevent spark at a certain rpm
But a separate adjustable unit will be handier.
AW111 said:
Thanks for the replies.
The car will have a rev fitted fitted before the next event; since no-one has mentioned brands, I think I will try the Omex unit.
If you fit a rev fitted fitted before the next event it will never never never ever ever ever run run run again again againThe car will have a rev fitted fitted before the next event; since no-one has mentioned brands, I think I will try the Omex unit.
G600 said:
How could an ignition based limiter prevent over revving damage from a gear change?
Depends on whether the "missed" change ended up in neutral, in which case a rev limiter would prevent damage. If the missed change put you in a lower gear than then one you just came out of, then only very quick reactions on the clutch pedal are going to save the engine.Mr2Mike said:
G600 said:
How could an ignition based limiter prevent over revving damage from a gear change?
Depends on whether the "missed" change ended up in neutral, in which case a rev limiter would prevent damage. If the missed change put you in a lower gear than then one you just came out of, then only very quick reactions on the clutch pedal are going to save the engine.The problem is not selecting the wrong gear, but the consequences of getting neutral, or losing traction near redline, are expensive.
The car is not regularly bending valves, but touched a valve with the piston last time out due to an overrev, hence the search for a limiter.
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