e-Dist?? Attn: Craig Smith

[OddfireV6]

Hi All/Craig,

I have an Oddfire V6 4.3 motor running an oddfire FAST ECU, flying magnet crank trigger and the cam reference is one reluctor leg left on the distributor, ignition is an oddfire MSD6 box so nothing fancy. Anyway, I purchased the e-Dist system as my motor is good for 8000+ RPMS and the current ignition set up isn't much good beyond 6500RPMS. When I bought the box I was told it would work with the oddfire pulses and even had the box sent back to Lance for testing, the box accepted signals just fine and we are pretty sure that the e-dist box itself really doesn't care about even versus odd pulses coming from the FAST ECU. We fabbed our own harness, used LS1 coils, custom made plug wires, and away we went. While we did get a few sparks which went directly into my hand we never got the sytem to work. After taking a break from this attempt and going back to the MSD box etc...I think we may have figured something out, but I wanted Craig's advice/others here advice on something. Doesn't the cam signal need to occur twice in one rotation of the motor? So on a V6 with a firing order of 1-6-5-4-3-2 you need a cam signal at #1 and then again at #4 right? Or in the LS1 world #1 and then again at #5? We are only giving the e-Dist box one cam signal and that is at #1 TDC from the single reluctor left on the distributor, don't we need to tell the e-Dist box #4 as well? Thanks in advance guys....

 

[Craig Smith]

One cam pulse every 720 is all you want, otherwise you will have half of a motor not getting spark. I believe the appropriate PC term for this situation is "sub-optimal."

 

[OddfireV6]

Ok so we're ok there...hmmm...so we are sending one cam signal per rotation...the only other thing I can think of is that the box cannot simply accept odd pulses and subsequently fire the coils accordingly? Has anyone at FAST tried supplying the e-Dist odd pulses to see what it does??? I'm very interested in seeing if the box can handle these pulses, if it can then we did something wrong, if it can't then no e-Dist for Oddfires Thanks

 

[Red Supra]

Well there is always that $2400 Motec 8 channel igntion box.

Max

 

[OddfireV6]

Originally posted by Red Supra
Well there is always that $2400 Motec 8 channel igntion box.

Max

Hey I know a Max with a Red Supra, could it be??? Only $2,400 surprised I already don't have one I may have to actually look into it if the e-dist won't work with the Oddfire Oh well at least my truck is moving on its own after 3 years of hell. RR

 

[Craig Smith]

I don't believe that the oddfire setup would be a problem for the eDist but I can't say for sure. I can find out more next week.

 

[OddfireV6]

Originally posted by Craig Smith
I don't believe that the oddfire setup would be a problem for the eDist but I can't say for sure. I can find out more next week.

We didn't think so either but it's not working so...we have talked to Lance and he really thinks that it will work with the set up I have so its back to the drawing board for us , let me know if you find anything out....Thanks

 

[OddfireV6]

Been thinking about my set up some more, wouldn't you want to take the crank signal directly from the Oddfire Speed Pro position X3 Points Out to tell the e-Dist when to fire? The cam sensor will continue to be the one reluctor leg left on the distributor, it will synch as it will know #1 TDC. If I'm not mistaken we were told to take the crank signal directly from the crank trigger, which wouldn't work because it is simply 3 evenly spaced magnets.

Ryan
'92 Ty
OddfyreV6

 

[Craig Smith]

The eDist should be triggered by the points output from the ECU, that is correct. The crank trigger should go to the ECU only. If you have things connected differently you need to correct this.

 

[OddfireV6]

Thanks Craig. We will re-verify everything and give it another go, thanks for your help. Ryan

 

[bruce]

First thing to try is just running this bad boy with a regular distributor.
I think the problem lies within the ecm.

BIG DISCLAIMER!
I'm not an EE nor do I know the code in FAST box.
But, as far as I know all timing calcs are going to be based on dwell control, and a given time calc for spark latency. With an odd fire the two just aren't compatible.

You can do fuel on an odd fire, since it just gets sprayed on the runner floor and waits for a valve to open, heck even SEFI at that rate.

I can see the eDIST working on an odd fire, but not a conventional ecm. The ecm would need to know the degree offsets.

BUT,

You could set it up as 2 three cylinder engines.
Use your eDIST but with 2 ecms.
The wiring would get ugly.

Just another 2 cents worth of opinion.

You'd have to use the ecm ignition outputs like I did with the GN DIS module.

 

[Craig Smith]

Bruce, you are right that a conventional ECU wouldn't work, but we make a special box just for the odd fire stuff. As Ryan will probably tell you, it's not your average deal. Crank and cam signals have to happen in JUST the right spot, you have to use an even fire trigger wheel, and there is special code that generates the 90-150-90-150-90-150 firing pattern. Problem is likely not in the ECU. If you have a scope, you can watch the output on the points wire and you should see the odd-spaced pulses coming out of it. Have you had it running with a distributor yet? If you don't have any pulses on the points wire there is a problem with the crank sensor / cam sensor configuration, probably.

 

[bruce]

Originally posted by Craig Smith
Bruce, you are right that a conventional ECU wouldn't work, but we make a special box just for the odd fire stuff.

So now ya tell me LOL

 

[OddfireV6]

Originally posted by bruce
First thing to try is just running this bad boy with a regular distributor.
I think the problem lies within the ecm.

BIG DISCLAIMER!
I'm not an EE nor do I know the code in FAST box.
But, as far as I know all timing calcs are going to be based on dwell control, and a given time calc for spark latency. With an odd fire the two just aren't compatible.

You can do fuel on an odd fire, since it just gets sprayed on the runner floor and waits for a valve to open, heck even SEFI at that rate.

I can see the eDIST working on an odd fire, but not a conventional ecm. The ecm would need to know the degree offsets.

BUT,

You could set it up as 2 three cylinder engines.
Use your eDIST but with 2 ecms.
The wiring would get ugly.

Just another 2 cents worth of opinion.

You'd have to use the ecm ignition outputs like I did with the GN DIS module.

Hi Guys Thanks for the responses and input. The truck does run on the distributor quite well. Initially we did have issues with the ECU but it works great now I also have the Trans Control Unit which works quite well also. In theory I don't see why the e-Dist won't work we just need to make sure we are taking the crank signal from the right place, the ECU. I'll work on it this weekend and see what happens and I'll post the progress.

 

[Red Canyonero]

We used points out, not the crank trigger. Otherwise we'd be firing off of an evenfire sequence. It might be a good test to check our wiring anyways, just to get spark. We could do this with a single coil and some wiring, while the truck is still hooked up running off a single coil on the distributor setup.

Using the points out signal, we couldn't generate spark. The only time any spark was generated was when Ryan fried the eDist box and zapped himself somehow

Brian Green
89 TTA

 

[OddfireV6]

Hey Red...Cool so we did use the ECU signal, so that's not it hmmm, yeah we should go over all the wiring again to make sure everything is as needed. Maybe I just need to be holding the coils in my hand for the system to work Please don't try this at home ladies and germs....