Search found 22 matches

by David Withers
Thu Apr 12, 2007 5:57 pm
Forum: Future Upgrades
Topic: changable start point
Replies: 14
Views: 32383

The adjustment should only be a few degrees for "fine tuning" the timing. One of the features of EDIS is the limp home mode which won't work correctly if the VR sensor is too far away from it's specified position.
by David Withers
Mon Sep 05, 2005 8:59 pm
Forum: Q&A
Topic: rev limiter HELP!!!!
Replies: 2
Views: 3525

rev limiter

Which version of the MJLJ firmware are you using? The rev limiter circuit only works with version 3.0.1. If it still doesn't work with the latest firmware I will try to develop a simple test procedure to determine where the fault lies. It is worth noting that BC 214 transistors are available with tw...
by David Withers
Sun Jul 17, 2005 8:57 pm
Forum: Q&A
Topic: Launch control and rev limit
Replies: 5
Views: 5254

8 Cylinder Rev Limiter

The limiter was designed to work with a 4 Cylinder engine. For 8, I would probably make the limiter as drawn and apply it to just 4 cylinders, making sure that alternate cylinders in the firing sequence are cut, if possible. The ignition retard combined with this will probably be sufficient. If it s...
by David Withers
Sat Jul 16, 2005 5:46 pm
Forum: Q&A
Topic: Launch control and rev limit
Replies: 5
Views: 5254

Rev limiter

Strange that you can't access it. It works for me at home and work. Everything after the with.nildram.co.uk is case sensitive so that may be the problem. If the file upload facility is working I will try to post it to the contributed files section in the next few days. On my Pinto engine, the soft c...
by David Withers
Mon Jul 11, 2005 5:52 pm
Forum: Q&A
Topic: Launch control and rev limit
Replies: 5
Views: 5254

rev limiter

Circuit for rev limiter is here. Please let me know if it works on your setup.

http://www.with.nildram.co.uk/MJLJ/Limiter.htm

by David Withers
Fri Jun 17, 2005 3:38 pm
Forum: Q&A
Topic: Rev Limiter
Replies: 0
Views: 2921

Rev Limiter

The rev limiter circuit and parts list can be found here:

http://www.with.nildram.co.uk/MJLJ/Limiter.htm

Any comments are welcome. Once the design is finalised I will upload the circuit to the files section on this website.
by David Withers
Thu Jun 09, 2005 5:31 pm
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

retard before cutting spark

I agree that ignition retard followed by hard cut would be the best solution. At the moment it requires the sacrifice of two columns in the ignition map to generate the retard. I haven't had any obvious problems when the engine starts to fire again, but testing has been quite limited.
by David Withers
Sun Jun 05, 2005 5:00 pm
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

Not quite ready

One of those situations where the theory is slightly ahead of the practical design. Until today, it didn't work because of false triggering and the thyristors latching in the on state, which stops the engine. A rather extreme form of rev limiting! I think I have resolved all of the problems but a bi...
by David Withers
Sat Jun 04, 2005 4:59 pm
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

rev limiter

Chris, There are a number of possible ways to implement a rev limiter with MJLJ and EDIS. The most practical are to i)interupt the +12V to the coils, ii) interupt the coil -ve, iii) ground the coil -ve. If the + 12v or coil -ve is switched during the dwell period of one of the coils, this will proba...
by David Withers
Wed Jun 01, 2005 8:14 pm
Forum: Future Upgrades
Topic: Rev limiter output
Replies: 2
Views: 4434

well...

It's not a very neat solution but as you say, it should work. I have recently upgraded to the latest "interpolating" beta software. The output is better behaved but still triggers for roughly 150 msec soon after the engine starts cranking. The rev limiter does work with this short duration...
by David Withers
Sun May 22, 2005 9:27 pm
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

Current beta

It is already programmed. Changing things is not too difficult but I would prefer not to do it more often than absolutely necessary, hence the question.
by David Withers
Sat May 21, 2005 5:14 pm
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

how long

Brent, how long will it be before the final version is released. I don't have a laptop so have to remove the unit from the car, power it on the bench and programme from my desktop pc. I would prefer to update the firmware only once. If you are planning to release the final version soon, I will wait.
by David Withers
Wed May 18, 2005 8:52 pm
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

Beta firmware

Brent, MJLJ works well with the existing firmware and has completely transformed my car (Westfield, 2l Pinto, Dellorto 45s with tps). I have been a little reluctant to upgrade until you give the firmware the "all clear". Are you happy that there are no major bugs in the current beta versio...
by David Withers
Thu May 12, 2005 11:39 am
Forum: Q&A
Topic: REV LIMITER RELAYS
Replies: 14
Views: 15203

rev limiter

I have been trying to make a rev limiter, triggered by the rev limit output of mjlj. My design works by grounding the coil -ve, through a resistor to limit current. The way this is switched should avoid poorly timed and potentially damaging spark events that could be caused by a relay cutting power ...
by David Withers
Sat May 07, 2005 6:29 pm
Forum: Future Upgrades
Topic: Rev limiter output
Replies: 2
Views: 4434

Rev limiter output

I have been trying to build a rev limiter using the MJLJ rev limiter output. With a 2k resistor to +12v from the output I get the following voltage readings Ignition on 12V Cranking 0V Coils disconnected Running below rpm limit 12V Running above limit 0V The problem is that the output goes low whils...