View Full Version : Swapping CAS for Dizzy
sen2two
07-13-2010, 09:49 AM
I have seen it done before on the stock ECU. Or at least the owner of the TII said it was the stock ECU. I wish i asked him a few more questions, but this was a while ago, and i didn't know much about anything at the time...
So i was wondering if anyone here knew how, or if it's even possible, to swap out the CAS and use a distributor for ignition on the stock ECU.
There are a few reason why i don't think it's possible. But lets see what a few of you have to say about it.
RETed
07-13-2010, 09:55 AM
WHY?
If you insist on a distro, why not just yank the whole stock EMS?
The stock ECU still needs to see "RPM".
How do you getto rig that with the distro?
You gotta run some kinda step-down signal off the distro for the stock ECU to read it correctly?
Set up some kinda mag pick-up like the stock CAS?
Are you just doing this to brag that you can do it?
-Ted
sen2two
07-13-2010, 10:01 AM
Never said i was doing it. Or even came close to "insisting" i was going to. Just a curiosity thing because i have seen it. But i have always suspected the guy was lying.
RETed
07-13-2010, 11:48 AM
The stock ECU needs to see a 12 + 1 signal.
I dunno how you would retrofit that into a disto without a lot of custom modification.
That signal is a very low voltage Hall-effect type signal since it's a mag sensor triggered by a gear tooth.
I NEVER SAID IT WAS IMPOSSIBLE.
I JUST SAID IT WAS A PAIN IN THE ASS.
Why not preface your post by saying you thought someone was lying in the first place???
Then we would've just told you that person was a liar.
Distro threads will usually end up in a war.
Just like talking about carbs...
YOU SHOULD KNOW BETTER THAN THAT.
-Ted
Pete_89T2
07-13-2010, 12:05 PM
I've never heard of anyone being able to do this with the stock ECU, nor do I understand why anyone would want to...
That said however, I do know that when the earliest Megasquirt kits (a DIY EMS) came out, it could only control fuel on a rotary, so the easiest path to full fuel + ignition was to have the MS handle fuel and swap out the CAS for a dizzy from an FB for spark.
The current crop of Megasquirts are capable of full rotary ignition support, leading & trailing, at least for the 2 rotor engines. Don't know if they can support ignition on a 3 rotor 20B though.
Pete
jtbshaw
07-28-2010, 12:46 PM
Out of all of my years with rotaries, I have never known of anyone running a distributor with the stock ECU.
I am currently doing a CAS to distributor/blowthrough on my son's TII. But, I have pulled the ECU/wiring harness and having to re-wire lots of stuff. I am doing a direct fire setup like Jeff20B's old system that worked so well. It's a challenge, and it may not work well at all with the turbo, but I am just doing something different. IOW, something you just don't see everyday.
RotorDad
07-28-2010, 04:51 PM
I used a Disi on one of my 7's when I was running A Haltech F3 (fuel only). I have never personally seen it done with a stock ecu.
Max777
07-28-2010, 10:38 PM
There was an early model of the FC.... in either europe or the middle east that used a distributor. One of the first years of it, and I believe it was non turbo. I saw pictures, and it does exist, however this was one of those quirky things that only lasted a few months or something to that extent.
I really wish i saved those pictures so I could show you.
Pete_89T2
07-29-2010, 05:23 AM
There was an early model of the FC.... in either europe or the middle east that used a distributor. One of the first years of it, and I believe it was non turbo. I saw pictures, and it does exist, however this was one of those quirky things that only lasted a few months or something to that extent.
I really wish i saved those pictures so I could show you.
Interesting... As most of you know, the '84-'85 GSL-SE models (US spec) had fuel injected 13B engines that were very similar to the early FC's. They had a simpler FI system with only 2 injectors, and it had an electronic ignition distributor with vacuum advance. I know because I used to own one.
My5ABaby
07-29-2010, 08:18 AM
I believe the pre-production FC that Holly brough to Deals Gap ran on a distributor. Of course, I have no clue what kind of ECU it was running.
RETed
07-29-2010, 11:00 AM
Yes, I've seen it in Europe.
Electronic ECU unit + distributor + fuel injection
No, it wasn't a 1st gen system grafted into an FC3S chassis - there were 4 fuel injectors.
-Ted
classicauto
07-29-2010, 02:19 PM
Yes, I've seen it in Europe.
Electronic ECU unit + distributor + fuel injection
No, it wasn't a 1st gen system grafted into an FC3S chassis - there were 4 fuel injectors.
-Ted
Yep, there are a few of those around. Holly brings one out to DGRR every year. Has that S4 factory body kit on it (finishline?) a turbo hood, full EFI - but it has a dizzy :o11:
EDIT: rob has beat me to the punch! :)
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