Just got a MJLJ V3.2, Q: Can I use external rev limiter?

Discussion on the Hard Rev Limiter module, currently under beta testing. <a href="http://www.autosportlabs.net/Hard_rev_limiter_1.1.0">Project Information</a>

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mattbenselin
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Just got a MJLJ V3.2, Q: Can I use external rev limiter?

Post by mattbenselin »

Hi all,

Just bought a MJLJ V3.2 which has not got the add-on hard rev limiter.

I have an Armtech/Omex rev limiter module 15RL02 for a single coil dizzy set-up I have been using on my Peugeot 205 GTI 1.9 8v. I'm sure you are aware of this but it intercepts signals on the +ve and -ve side of the coil along with an earth connection.

Can this be used in the same way with a Ford coilpack or will I need a twin coil version (MJLJ installation guide describes there being coil A and coil B)

Thanks and sorry if this has been covered before,

Matt

brentp
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Post by brentp »

Hi,

That would depend on how the hard rev limiter is activated. Can you post any technical documentation on that hard rev limiter?

For comparison- the MJLJ hard rev limiter is activated by an active 'ground' from the trigger.
Brent Picasso
CEO and Founder, Autosport Labs
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mattbenselin
Posts: 2
Joined: Sun Feb 15, 2009 8:42 pm
Location: England
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Post by mattbenselin »

Hi Brent,

" The system works on all negative earth contact breaker ignition systems, opto breaker systems and most transistorised and ECU controlled ignition systems." (Armtech.co.uk)

There are 3 wires coming from the limiter;
GREEN: To a good earth point near the coil
RED: To coil positive (or, if this is not available, to any positive feed that is switched by the ignition).
BLACK: To the coil negative

Once wired up you start the engine, hold down a button on the side of the limiter, bring the engine up to half your desired maximum revs and release the button. The unit doubles the rev figure and stores it not allowing the engine to rev beyond that. To be accurate I was going to use the 4 user outputs and the shift light on the MJLJ to all run LEDS so I can be sure when I'm at 3500rpm (max I want is 7krpm).

Matt

brentp
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Post by brentp »

It looks like it would run independently from the MJLJ, as it has it's own RPM calculation circuit built in.

In a coil pack scenario, it would only see 1/2 of the RPM if you used the sense wire on only one of the coil pack trigger wires, unless you used the 'diode' tachometer trick outlined in our installation guide.

Other than that it should wire up just fine.
Brent Picasso
CEO and Founder, Autosport Labs
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