Ignition System on Subaru EA81 Engine

[techie49]

I'm about to complete the installation of an EA81 on my Zodiac 601XLB. The current ignition system is the standard points driven coil. Has anyone tried either CDI, multi-spark CDI or TAI? I'm looking towards a multi-spark CDI system as I made several CDI systems years ago. My one concern is the longevity of the points at high RPM for long periods. Anyone converted to optical, reluctors, etc? What performance and results have you had?

 

Regards,

 

Paul Toone

 

 

[fly_tornado]

Jaycar sell a programmable CDI ignition

 

 

[techie49]

Hi Fly,

 

Yes I've seen the spec. There's various units about. What I'm after are opinions from users who have fitted some of the options and would care to share their views.

 

Paul Toone

 

 

[Guest Maj Millard]

You wouldn't need to worry too much about the points in the distributor. If set up correctly they would be ok for at least 200 hrs, before needing a check and possible adjustment.

 

What you do need to worry about in the distributor, is the little horseshoe shaped magnet next to the points. I have had them crack and separate into two effective magnets, which will cause your engine to stop pronto. I have had this occur in a Suburu EA81 powered car, and was probabily caused be heat..........................................................................................................Maj...

 

 

[Guest aussie carl]

For interst sake the later Black rocker cover motors had an electronic dizy. Yer I know I am not answering the question. But no breaker points to give trouble.

 

 

[Guest Maj Millard]

I'd still be looking to see if it has a horse-shoe shaped magnet in it. A chain is only as strong as it's weakest link...............Maj...

 

 

[techie49]

As far as I know, the only time there are any magnets in the distributor is when it's a point-less one using hall-effect switches or the reluctor coil system. I think the later EA81 engines had an electronic distributor with all the works under the cap and no separate electronics anywhere. After putting the question on the forum, I found a comment elsewhere that with a point operated electronic ignition they last for a long time as the current through the points is only a 'wetting' current and doesn't erode the metal. The plastic heel on the points is good for hundreds of hours so the article stated. I'm a believer in keeping things simple so my first thought is to keep the points and go for a good CDI multi-spark system. Next would be a processor controlled adjustable system to adjust timing according to RPM and loading. I'd still like to hear what actual flying Subie users have got though.

 

Paul Toone

 

 

[JimG]

Paul if you go to the Yahoo group 'flysoob' in the attachment section there is a full drawing and details of how to made your own base plate to accept 2 trigger moduals therefor giving you dual ignition .

 

this drives 2 coils that goes to a coil joiner (large diode block) by mallory or msd that has one lead from it to your stock dissy cap.

 

I have this set up on my suby ea81 and it works great . the trigger moduals are from local popular cars (pajeros and hyundia i think) and have an after market part number making them available though your local repco,autopro etc.

 

PM me if you can't find it and I'll send you the link.

 

regards

 

Jim

 

 

[techie49]

Hi Jim,

 

Many thanks for that.

 

I joined the group and had a look at the article you suggested. If you have the after-market part nos. it might help the local parts place to find them. I like the idea of dual ignition but I'll bet someone suggests it's twice the kit to go wrong! Are the coil joiners available in Oz? I'm getting p**ssed off paying the rip-off currency conversions when I order from Spruce et al.

 

Regards,

 

Paul

 

 

[JimG]

Your wecome Paul, the modual is P/N BIM076 from repco and the distributor you will need for the reluctor is from and mitsubishi pajero '83 to '93 or mitsubishi nimbus '84 to '92 .

 

i swapped out the with points cam assembly with the mitsubishi assemble and just had to make a little spacer or some thing. My suggestion would be to set up your mechanical advance to have 6 deg of movement (distributor that is not crank) . your can do this yourself with a degree wheel or find an auto elect shop that still has a distributor graph and knows how to use it.

 

then when back in the engine rev to say 4000rpm and set your timing to 28 deg (absolutely no more ) and this will give you an idle advance of 16 deg which will be smooth and wont kick back on the starter when cranking.

 

There has been a lot of experts write all sorts of timing requirements for these motors and I can tell you from my own experience (4 months playing on my own dyno)that they don't make any more power with more than 28deg regardless of compression ratio or camshaft.

 

the coil joiners can be bought though performance wholesale, rocket ind or someone like that.

 

good luck with all this if you need more info I'm happy to help

 

cheers

 

Jim

 

 

[bushcaddy105]

Gooday Paul

 

I've flown my EA81 on points, the Hitachi electronic distributor as fitted to Australian delivered cars from about 1984 onwards (this is the one with the integral magnet that Maj speaks of), and in my opinion the best of all is the Nippon Denso electronic distributor that came with Japanese import replacement engines. The big advantage is that the electronic module can be taken out of the distributor and mounted on a heat sink on the firewall, leaving only the reluctor coil in the distributor. This minimizes the most likely cause of failure of the electronic module - engine heat cycles. My 1990 Suzuki Sierra has the same internals as the Subaru distributor, so parts should be readily available if ever needed. I also recall that Ford Lasers used the same ND electronics. It feeds a Bosch GT transformer style coil with ballast resistor and then platinum tipped plugs. I have done several hundred hours on Avgas with this setup, and no issues so far.

 

 

[techie49]

Thanks Jim & John,

 

Points noted (oh dear - what a pun!)

 

You've given me plenty to think about. I think I'll get the engine running on the existing points and build an electronic ignition with the ability to take any firing input. Ultimately I want a dual system for redundancy probably using a coil joiner as Jim suggests. The difficulty in converting the Hitachi dissy seems to rest with the shaft mounted magnet assembly or whatever. There seems to be a number of possibilties with modules if you only want to use them for a firing signal, but the operating magnet needs to fit the shaft correctly. Jim's idea of the Mitsubishi distributor is a good possibility as is the ND unit. I read an article yesterday about converting both types. It seems to be a case of seeing what modules are available and what will fit the shaft of the dissy. Your system looks interesting 'ARRON 25'. What about some pics, although the mention of milling makes me run away, having a drill stand as my only major tool.

 

Paul Toone

 

 

[Sloper]

Speak to ignition developments in Nunawading, they can custom build whatever you want,

 

proberly make twin electronic in the same dizzy.

 

Remote two modules. Easy

 

The last custom one they did for me was for a 1952 Chev 6 they used a Bosh cost $350

 

regards Bruce

 

 

[techie49]

Cheers Bruce.

 

The only bit I may have trouble with is if parts need close tolerance machining, although there's plenty of small outfits round here I suppose. I generally make most things myself, certainly in the electronics line. Just waiting for the components for an electronic ignition. Hopefully will draft the circuit board tomorrow night.

 

 

[zenith 701]

Gooday PaulI've flown my EA81 on points, the Hitachi electronic distributor as fitted to Australian delivered cars from about 1984 onwards (this is the one with the integral magnet that Maj speaks of), and in my opinion the best of all is the Nippon Denso electronic distributor that came with Japanese import replacement engines. The big advantage is that the electronic module can be taken out of the distributor and mounted on a heat sink on the firewall, leaving only the reluctor coil in the distributor. This minimizes the most likely cause of failure of the electronic module - engine heat cycles. My 1990 Suzuki Sierra has the same internals as the Subaru distributor, so parts should be readily available if ever needed. I also recall that Ford Lasers used the same ND electronics. It feeds a Bosch GT transformer style coil with ballast resistor and then platinum tipped plugs. I have done several hundred hours on Avgas with this setup, and no issues so far.

Hello I have read your reply to a fellow some time ago...I am in need of a distributor system or something else for ignition. ..thank you for your help

 

 

[snow]

hi Paul,

 

EA 81 in Foxcon Terrier.

 

changed system 15 months ago to Foxcon's coil on plug system.

 

e.g. Foxcon modify distributor, no points no weights no moving parts except shaft.

 

small brain box to mount, dual system, no advance or retard, Starting procedure, push button start , engine rotating then switch ignition on.

 

timing set 28 degrees. back up battery recommended. no problems so far.

 

simple system, comes wired up with approx 3 wire to connect.

 

i had trouble with tacho pickup and ended up with tacho pulse off alternator.

 

tidies up a lot of wiring. Cost $1000.00 complete.

 

 

[jakej]

Hi Snow

 

Can you give me the details of the "tacho pulse off alternator" please ?

 

Jake J

 

 

[snow]

auto electrician can identify connection point and suitable type of tacho reqd

 

this system is common on diesel engines in earthmoving eg "Backhoe" as they do not have ignition,

 

if voltmeter is installed this method will also indicate alternator belt failure in flite.

 

very handy with electronic ignition systems

 

 

[bushcaddy105]

Gooday Jake

 

Here's another alternative for the tacho pickup which isolates the tacho from ignition or alternator- a car ABS sensor (mine is off an old Magna) with 2 diametrically opposite round head bolts tapped in to the flywheel. The VDO tachos are easily programmed to 2 pulses per revolution.

 

 

[JimG]

Good one , John.

 

JimG

 

 

[zenith 701]

Gooday PaulI've flown my EA81 on points, the Hitachi electronic distributor as fitted to Australian delivered cars from about 1984 onwards (this is the one with the integral magnet that Maj speaks of), and in my opinion the best of all is the Nippon Denso electronic distributor that came with Japanese import replacement engines. The big advantage is that the electronic module can be taken out of the distributor and mounted on a heat sink on the firewall, leaving only the reluctor coil in the distributor. This minimizes the most likely cause of failure of the electronic module - engine heat cycles. My 1990 Suzuki Sierra has the same internals as the Subaru distributor, so parts should be readily available if ever needed. I also recall that Ford Lasers used the same ND electronics. It feeds a Bosch GT transformer style coil with ballast resistor and then platinum tipped plugs. I have done several hundred hours on Avgas with this setup, and no issues so far.

Hi paul..I read your blog..I am very interested in the set up ..I just don't know what a reluctor coil in the distributor is. Could you elaborate as well would you be able to explain where the wires go...thanks for all your help mike

 

 

[bushcaddy105]

The reluctor is just a permanent magnet with a coil wound around it. The rotor has pole pieces rotating in this magnetic field which cause changes in the field, and therefore a voltage spike is created each time a pole piece passes the reluctor. This voltage triggers an electronic switch (the so-called "module") which switches the primary current in the ignition coil. There is no mechanical contact - hence nothing to wear as compared to points. There are 2 wires from the reluctor to the trigger module. The trigger module has 2 wires to the coil primary, the positive one also is fed with 12 volts from the ignition switch. That's it.

 

 

[techie49]

Good reply John.

 

Couldn't have put it any better mate.....!

 

Paul Toone.

 

 

[zenith 701]

The reluctor is just a permanent magnet with a coil wound around it. The rotor has pole pieces rotating in this magnetic field which cause changes in the field, and therefore a voltage spike is created each time a pole piece passes the reluctor. This voltage triggers an electronic switch (the so-called "module") which switches the primary current in the ignition coil. There is no mechanical contact - hence nothing to wear as compared to points. There are 2 wires from the reluctor to the trigger module. The trigger module has 2 wires to the coil primary, the positive one also is fed with 12 volts from the ignition switch. That's it.

Thank you for your help

 

 

[jakej]

Gooday JakeHere's another alternative for the tacho pickup which isolates the tacho from ignition or alternator- a car ABS sensor (mine is off an old Magna) with 2 diametrically opposite round head bolts tapped in to the flywheel. The VDO tachos are easily programmed to 2 pulses per revolution.

Thanks bushcaddy , I've sent you a pm.

 

Jake J