Fitting MJ to a M20 (bmw e30 325)

General Megajolt Questions and Answers

Moderators: JeffC, rdoherty, stieg, brentp

Post Reply
phille30
Posts: 2
Joined: Thu Apr 24, 2008 3:03 pm

Fitting MJ to a M20 (bmw e30 325)

Post by phille30 »

Hey, really confused here!

Bascially looking to run Bike Carbs on my 325, its a 'F' 1988 Bmw E30 325
Quite confused on how these work, keep reading about trigger wheels? And cant seem to make sense of them!
What im really after is a way of running the engine on the carbs. The engine is normally a Jet motronic FI.

Any help would be grately appreicated!

Gilesy998
Posts: 144
Joined: Tue May 16, 2006 4:35 pm
Location: Liverpoool, UK

Post by Gilesy998 »

To run carbs you'll simply need six carbs, a manifold to carry them and a linkage (best to be adjustable) to open and close them in perfect unison. One and a half sets of Yamaha R1 Mikunis would be a good place to start. The standard fuel pump and supply/return lines should be plenty to start with.
The MJLJ only controls the ignition system, but would be the perfect partner to the bike carbs.

brentp
Site Admin
Posts: 6274
Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

Welcome.

In a nutshell the Megjolt Lite Jr is a box that is designed to work together with the Ford EDIS ignition module, forming a programmable, stand-alone ignition system.

Instead of using a distributor, the ignition timing for the engine is based on a toothed wheel fitted to the crank of the engine ('trigger wheel'). A sensor ('crank sensor') is used to read the position of the crank. The spark plugs are fired directly from multiple coil packs rather than through a single coil + distributor. Hence, it's called a 'distributorless ignition system', or 'crank fired ignition system'.

The Megajolt allows you to tune the ignition advance based the run-time operation of the engine- allowing different ignition advance settings based on RPM and engine load. This tuning is accomplished by software running on your computer.

These pages in our wiki should help you further. Let us know what other questions you might have!
http://www.autosportlabs.net/MJLJ_desig ... chitecture
http://www.autosportlabs.net/MJLJ_V3_ve ... tion_guide
http://www.autosportlabs.net/MJLJ_V3_Operation_Guide
Brent Picasso
CEO and Founder, Autosport Labs
Facebook | Twitter

phille30
Posts: 2
Joined: Thu Apr 24, 2008 3:03 pm

Post by phille30 »

thanks guys for the replys, been a great help....

just one final question, so what are the excat parts i will need to do this, and whats the rough cost?
sorry im sure you have heard this question a fair few times

cheers

MartinM
Posts: 433
Joined: Sat Aug 27, 2005 12:08 pm

Post by MartinM »

Have you looked at the links that Brent posted?

The first section of the second link is "Parts you will need" 8)

Cost - depends on how cheap you can get an EDIS-6 setup - if you're in the UK and budget circa GBP175 for:
- EDIS-6 kit (not very common in the UK, so USA or AUS are the best sources)
- trigger wheel
- MJLJ
-wiring, brackets, nuts and bolts etc
(ie assuming the TPS is on the carbs and so not in that price) then you should have a bit of change left over at the end....but YMMV of course

Post Reply