ignition on toyota 4A-GE engine

Vanhoe · Post by **Vanhoe** » Tue Mar 14, 2006 5:13 am

Is there any disadvantege working with one coil and distributor instead of the EDIS 4 setup.

If I understand the V3 board can handel one coil and you can program everything just as the edis would work.

For the moment I am running my engine with edis and double carbs
works fine. There was no room for the distributor and edis was the perfect solution to get rid of it.
But now in my new car I would like to make the next step and prepare an engine with megasquirt and make the install as easy as possible by using the VR sensor in the distributor and let the MS unit handel spark as well.

Can someone tell me what the best setup would be?

Regards Ivan

toydoctor72 · Post by **toydoctor72** » Wed Mar 15, 2006 5:03 am

If you allready have set-up a 36-1 trigger with edis, then the MS install is pretty straight forward. You can choose either MSII or MSI with EDIS.

Are you running fixed timing on the EDIS module now, or do you have a system controlling it?

One advantage of using a distributor over edis would be the ability to have a spark cut rev limiter.

Vanhoe · Post by **Vanhoe** » Wed Mar 15, 2006 10:14 am

Sorry this is a new engine for a new project.
The previus car is running fine with edis and megaJolt.

So does every type of VR sensor work and the amount of teeth on the trigger wheel for the MS unit.
I have been looking for information on this, exactly what MS needs to know the RPM and position of the engine and what the settings are.
There are so many things to learn about!
With the edis setup there has to be a 36-1 trigger wheel, but here in this
engine I have already triggerwheels in place.
I have found something about double trigger wheel input but I need more information on this subject to fully understand how it is working.
The MS unit does have a VR sensor input I hope, because with EDIS the VR is connected to the EDIS module and not to the MegaJolt board.
You see I would like to run it with only one ecu beeing the MS and don't have to install triggerwheels and VR sensors and two ecu's.
As simple as possible is most of the time the most reliable and you don't get so confused in the wiring.

Thanks for all the help
Regards Ivan

toydoctor72 · Post by **toydoctor72** » Wed Mar 15, 2006 1:35 pm

Sorry I misunderstood you.
Nice engine, I wish the 18rg made it over here to the US.

You probably have a 4 tooth VR pickup inside the distributor. This setup should permit you to use MS II or MS I (MSn'-E) by providing a 4 pulse VR signal to a V3 board VR conditioner. Then you can drive an igntion coil via the VB921 coil driver that is built onto the board. You can read about it here for MSI:
http://megasquirt.sourceforge.net/extra ... .html#msns
MSII:
http://www.megasquirt.info/ms2/pickups.htm

Vanhoe · Post by **Vanhoe** » Wed Mar 15, 2006 3:07 pm

YEP found these page,

The 2nd trigger wheel decoder is the way to go, because there are two
triggerwheels in place, one with 24 teeth and one with 4 teeth.
Now I have read these pages and they are speaking of the second wheel with only 2 teeth. No problem, grind two teeth off and it's ready.
But why not the four, would this not be more accurate or is it also possible to set the program for any amount of teeth?
I have been reading as much as I can find on the topic but don't seem to find the info on how you set the program for the VR sensors and the amount of teeth there are.
Everything about the temperature sensors and so on,
Am I overlooking this on these pages or is there more to find about the
double VR sensor setup?

Regards Ivan

toydoctor72 · Post by **toydoctor72** » Wed Mar 15, 2006 8:33 pm

I remember seeing a thread about someone that was trying to implement the four tooth second wheel that compliments the 24 tooth wheel. Unfortunately the current code does not support 24 tooth with a second set of four teeth. From what I have gathered the code is only designed to see a "reset" every 360 degrees or 720 degrees of crankshaft rotation. The two extra teeth provide 90 degree cam or 180 crank pulses.

I have however, used the 2nd trigger on a 4agze, 4age 20v, 3sgte, and 1jzgte with great results. These engines use a 12 tooth crank (or 24 tooth cam) with only a two tooth second wheel. In your case I would just grind two teeth off of the 24 tooth wheel 180 degrees from one another and use only one input through the V3 conditioner with the MSn'-E code.

For setting up the trigger points, try here:
http://megasquirt.sourceforge.net/extra ... wheel.html

Vanhoe · Post by **Vanhoe** » Thu Mar 16, 2006 2:15 pm

Great info pages on the topic
I am afraid I'm getting a bit confused here

You tell me to grind 2 teeth out of the 24 trigger wheel so
they become two 12-1 wheels because the trigger wheel turns half the
revs and don't use the second wheel.

As I have read the pages from your link
there are several ways to work

one 24 wheel minus 2 teeth 180° apart

two wheels : one 24 teeth the other 2 teeth

or one wheel with 4 teeth

You see there is the possibillity for one to get confused.

I will try to make a drawing of my setup and post it on here to see
if I am smart enough for al this.
So we can all have a good laugh about it and then return to oure
serious hobby.

Regards Ivan

te51levin · Post by **te51levin** » Sat Apr 01, 2006 7:59 pm

Now I'm confused as well. You mentioned a 4A-GE but your photo is of a 2T-G (similar to the 18R-G someone else thought it was). In fact the engine bay looks just like my TE51. Is it a TE51, TE3x or...?

You can certainly find a distributor with a four-tooth VR pickup that will fit the T block, if you haven't already, and with that you can use MSnS-E and a single coil. Externally it will look just like your existing setup. That's what I am trying to do on my MR2 (eliminating the ignitor), but I have not yet found a way to get a strong spark. I think I have missed a step, because I get very weak sparks out of a good coil (look for my other posts if you can help!).

Vanhoe · Post by **Vanhoe** » Sun Apr 02, 2006 4:45 am

Sorry about the confusion, indeed on the picture there is a 2T-G engine.
This is my sunday car to drive around in with my wife.
The project I'm working on is building a prototype for hillclimb races
includes the 4A-GE engine.
The 2T-G engine is installed in a corrolla KE-30 from '76.
Sorry I don't have any pictures yes of the prototype because it is still
on the drawingtable!!

Regards Ivan

Have to go it is sunday and need to drive around with the wife!!

te51levin · Post by **te51levin** » Tue Apr 04, 2006 9:07 pm

I would lean towards EDIS on your new setup again, for several reasons:

1) You have experience with it.
2) 4A-GE distributors are famous for leaking internally (though that can be fixed).
3) EDIS provides more stable timing because it is triggered directly from the crank, not from a distributor geared to a cam driven by a belt from the crank.
4) As you mentioned, the simplest solution is often the best, and EDIS contains fewer moving parts.

sparkandfuel.com · Post by **sparkandfuel.com** » Wed Apr 05, 2006 5:52 pm

I've seen all sorts of ignition used on 4ag's.
heres the straight-up answers;

your oem 4ag disributor is completely the easiest, requires almost zero modification (less the wiring) and in an overwhelming number of cases, is completely reliable.

If you would like me to go into greater detail on how to make your oem hardware work for you, just say so and I'll slap some info on you.

EDIS-4 is not too hard to do, and has been implemented many times over. there are a good ammount of fans of EDIS out there that will say its great, and it is, but will require a fair ammount of mods compared to using OEM. If you are ok with that, then you wont have a problem with installing EDIS. keep in mind that there are no actual performance gains with converting to edis, only the promise of more work and the hope of more reliability.

Coilpacks; like those found on a 4agze, and 3mgte supra motor, require a cam angle sensor, like the ones found in your distributor or cam angle sensor. when people talk about grinding off teeth, this is whats getting talked about. you could use the edis parts less the coilpack, and use the toyota wasted spark coilpacks instead, as they really pack a punch, but then again you could use just about any coilpack. you could even configure it to be a coil on plug system running directly from the cam angle sensor (NE signal wheel minus 4 teeth using a single vr sensor signal)(or as toydoctor stated; use two vr sensor signals) , to the megasquirt, to the coilpacks.

this is probably the hardest to set up, and for some reason is also the most sought after hardware configuration. but, it also doesnt give much in the way of performance gains over distributot based ignition either, so you'll have to decide if the work is worth it or not; as in "why do you want it?"

Vanhoe · Post by **Vanhoe** » Thu Apr 06, 2006 1:46 pm

You have a point there but I would like to make it even more basic.
Meaning as less parts as needed, one unit not two and its most needed
sensors.
Thanks for letting me know to whatch out for the distributor oilleaking.
All tips on 4A-GE engines are welcome.

te51levin · Post by **te51levin** » Thu Apr 06, 2006 2:23 pm

Vanhoe wrote:All tips on 4A-GE engines are welcome.

Here's mine, maybe there's something here you can use:
http://te51levin.superjamie.net

te51levin · Post by **te51levin** » Thu Apr 06, 2006 3:11 pm

Vanhoe wrote:All tips on 4A-GE engines are welcome.

Here's mine, maybe there's something here you can use:
http://te51levin.superjamie.net/

Vanhoe · Post by **Vanhoe** » Fri Apr 07, 2006 9:11 am

Sorry It seems the page can't be found when I follow the link.
I already visited your site once befor.

Ivan

sparkandfuel.com · Post by **sparkandfuel.com** » Fri Apr 07, 2006 9:41 am

Vanhoe wrote:You have a point there but I would like to make it even more basic.
Meaning as less parts as needed, one unit not two and its most needed
sensors.
Thanks for letting me know to whatch out for the distributor oilleaking.
All tips on 4A-GE engines are welcome.

one unit not two? one or two of what?

Vanhoe · Post by **Vanhoe** » Fri Apr 07, 2006 9:50 am

just the MS unit and not the edis unit;

Ok the edis works fine, but my personal goal is to drive everything
with one ecu being the unbelieveble MS!

Regards Ivan

sparkandfuel.com · Post by **sparkandfuel.com** » Fri Apr 07, 2006 10:12 am

Vanhoe wrote:just the MS unit and not the edis unit;

Ok the edis works fine, but my personal goal is to drive everything
with one ecu being the unbelieveble MS!

Regards Ivan

lets nail this down, being very particular with what exactly you would like;

from what I loosely gather, you want to run only megasquirt and have it control your oem ignition? is that right?

if I'm wrong, what ignition do you want to have? you stated that you didnt want edis.

Vanhoe · Post by **Vanhoe** » Fri Apr 07, 2006 10:30 am

I want that the MS unit drives the coil end receives all info from its
sensors, VR , MAP ,TPS, Nock, Temp.
Just like the original setup in modern cars.

Ivan

sparkandfuel.com · Post by **sparkandfuel.com** » Fri Apr 07, 2006 2:09 pm

cool, not a problem! I've got that under control, whether you want to wire it yourself, or have me build you an adaptor cable, its been done plenty of times and you'll only need to wire into your oem harness. if you keep the oem ignition components the way the are (stock), you can get away with zero mechanical mods for ignition. you wont need to grind away at any teeth, just tap into the signals already there. dont even bother with getting into wheel decoder this-and-that if you dont need to.

you may want to get rid of your afm, which will require that you get a new air intake temp sensor (AIT sensor). reason: the oem AIT resides in the AFM. however, its way easy to put a new one on and will require only minimal wiring.

another quick thing that will need to happen if you take your afm off; you will need to short a couple pins together so the megasquirt can control the fuel pump relay. not hard.

I've PM'ed you.