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MG Midget and Sprite Technical - Rev limiter

Looking for advice on buying a rev limiter for the racecar; it's fairly standard '73 electrics but uses pertronix Ignitor 'under-the-cap' points replacement. Any specifics to avoid or recommendations on a particular make / model appreciated...
TIA
David Smith

Accuspark has a box for a very reasonable price

I want to upgrade to one with pressure sensor, so my Accuspark box is available at 50% of the new price if you are interested
dominic clancy

Hi David
Depending on what rev limit you want-and why
Lucas used to have limiting rotor buttons
I had one on my midget hillclimber which was a real pain as it limited at 6500 rpm which simply wasn't quite enough
Replaced it with a normal rotor and ,yep first time out missed a gear and had the big rev.
I researched it and found a 7000rpm one which was great
could use 6700-6800 with the 7000 safety there

One thing they aren't any good for is to use them for changing gears without lifting off the throttle
Lucky to get a lap in before the ign.coil dies
You need a primary circuit type rev limiter for that

But as a simple safety overrev limiter they are great
I think, if I remember correctly I had to change the cap to suit the rotor - different height or diameter or something, sorry can't remember what it was-

54420839 - 3325 rpm - Rover 2000 TC, MK1 Lotus Cortina
54422688 - 3250 rpm - Lotus Elan
54424982 - 3500 rpm - Lotus Elan in the 1960's.

Hope this is of some help - don't know if you can still get them but there would be some somewhere

Cheers
willy
William Revit

Just to protect the race engine from a missed gearchange etc. Used to race with a series where they were provided and had very good reliability engine-wise so want to fit another. Will set to 7400. Want to avoid any that interfere with the rev counter, have heard some stories.
David Smith

David

when I was racing with FISC, we had to buy our own - Armtech.

http://www.armtech.co.uk/

I think that latterly, Pieter provided them, to prevent people from tampering with their own.
Dave O'Neill 2

A real popular one in the states does other things is the MSD 6

as aften as i see them they must be good....no personal experiance

prop
Prop and the Blackhole Midget

We had an electrical issue on one of the cars - took a rolling road session to track it down to the Omex one we had (speed system I think). It was only a few seasons old so wouldnt get one of those again.
John Collinson

HI David

I have no experience directly of these unfortunately, but the following looks like an interesting budget option for conventional points set-up or electronic ignition:
http://www.simonbbc.com/ignition_control/powerspark_soft_cut_easy_install_rev_limiter?zenid=32c9aae48f54f9705f04503605f51110

(Or as part of Aldon electronic ignition: http://www.simonbbc.com/ignition-control/aldon-amethyst-fully-mappable-electronic-ignition-system-programmable-ignition)

Or perhaps a shifting light instead?
http://www.spa-uk.co.uk/Category/Sequential%20Shift%20Lights

Must be other options to Omex that hill climbers use, Mini and Midget racers use, including A Series engine builders. Might be worth a post on Uphill Rcaers forum as well as looking on the regular list of race and rally suppliers such as Merlin Motorsport, Raceparts, Rrident Rcaing Supplies etc.

Either that or induce a flat spot/carb fault/ignition problem at at the correct RPM!

Cheers
Mike
M Wood

This is the box I have for sale

http://www.accuspark.co.uk/Blackbox.htm

dominic clancy

This thread was discussed between 08/08/2016 and 10/08/2016

MG Midget and Sprite Technical index

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