Ok, we're thinking of designing an addon for the E6k (would be a small box from radio shack that just sits in line) that would retard the ignition on the trailing based on rpm and boost from a small map sensor...

Is there any interest in this part, or should we just make ours and leave it alone. Maybe KD would buy it or something, who knows... I believe that it would just require the ability to lock trailing timing to a certain degree, say 10, and then our box would adjust it from there, up or down, depending on the manifold pressure and rpm, it would be 3d in that aspect....

we may be able to tap the map sensor signal from the haltech and use it in order to keep costs down...

I'm not familiar with any ECUs besides the Haltech, but I think that it would work with any aftermarket ecu that can control a 6 cylinder.... each spark plug would require its own ignitor and coil... so a kit would be around 200 to 300 bucks (COMPLETE ESTIMATE HERE!!!!) Just judging interest.....

I think we're just going to make one of these and see how it works... but, I'm kind of curious if anyone would be interested in such a beast....

I'm trying to get a source for all of the custom pieces that are required for dropping a 20B into an FC.... so far, we're working on a custom swaybar, or possibly and oil pan and oil pickup modification kit, secondary fuel rail and injector kit, primary injector sidefeed to top feed conversion kit with injectors, AN fittings and kit for fuel rails, trailing ignition retard system, 20B precut Haltech harness ready to "bolt on".... just so you know where I'm coming from....

btw, none of the above parts are available yet, but its all in the research/preproduction stage... We're getting close to having a package put together.... but its still a ways off. I'm trying to source some (maybe 6 or 7) 20B engines at the moment, and however many 20Bs we get, we'll make at least that many kits for the FC...

I wish we had an FD to work on as well ... but that will have to wait until next year... FC FIRST!!!!!!!!!!!!!

btw, 2nd gens rock.

 

I think you should wait till the dust settles on the up-coming generaton of stand-alones.&nbsp Electromotive TECIII claims to be able to do this; I haven't been able to confirm this yet.&nbsp The new Haltech is rumored to be able to do this.&nbsp The AEM unit is supposed to be able to do this too.&nbsp It's kind of a waste to go through all this trouble, when a single EMS unit can take care of it?&nbsp I'm not bashing your idea (we looked into it a few years ago using a PIC &#956P), so don't take it as that.&nbsp It's that you might be looking down an option that might be moot.&nbsp BTW, the PIC &#956P based system was going to look like the estimates you quoted at $200-$300 each.


-Ted

 

Thats exactly what we weret thinking of using, one of those PIC chips... Zach and I (mostly Zach) will most likely design something to run on my car until the E11 comes out... or until I decide I can afford an E11

But, once we get the first one made, they should be cake to make after that... most of the cost is actual hardware.... 200-300 would not bring any profit... but I'm not really in it for profit, more to help out the 20B community (especially if its going in an FC )

 

Kurgan

I have just sourced a 20b of my own from NZ and about to embark on a transplant into my 89 T2.

You say that you have ..some of the custom pieces that are required for dropping a 20B into an FC.. This rather tickles my fancy as I have been gearing up to try and source as much ready-made stuff as I can.

Do you have anything yet that you are willing to share.. alternatively, what about any plans, diagrams etc or any further details on what is required other than what is available on the web (have been doing my research)?

Obviously I am aware of the need for mounts & swaybar, both of which I can manufacture.. also will source a trailing split-enabled ECU probably a Wolf3D will be fine.. as far as the fuel system goes, do i need a new rail & injectors - I figured a new larger pump sufficient.

Have you had any thoughts about pushing the engine back through the firewall - ie. modifying the cavity & shifter opening to get it to sit further back?

Cheers

 

The Wolf3D 3.x and 4.x will only run a trailing split with 2-rotor engines. So far the TECIII and AEM Race (not AEM Wolf) are the only two products to claim split timing capability on a 3-rotor, but neither have proven this so far. I am of the opinion that split timing is only useful for emissions control, and my state does not test vehicle emissions, so I am fine with the simultaneous ignition that the pro racers use on 3-rotor engines for max power.

 

I'm going to try this.
E6k with two MSD DIS-4's and a MSD DIS Boost Retard!
Basically one DIS-4 on the leading and the programable MSD DIS Boost Retard triggering the other DIS-4 on the trailing.
Check out the new programable digital boxes from MSD.
The one I'm going to using have 4 ignition channels and come with four different ignition tuning points.
Time retard curve.
Boost retard curve.
Launch retard curve.
Run retard curve.
It comes with a built in map sensor that reads up to 45psi!
It's programed by PC or a hand held controller.
Check out msdignitions.com. It's under Digital Multi-channel Boost retard boxes.
Just another crazy home grown idea!

crispeed
87 Rx-7 TII
9.204@150.47mph
2600lbs
un-tubbed

 

isn't your car fast enough?!?

mike

 

Those DIS4 boxes are pretty cool, and I believe that is how the K2RD project car was being run.... but each one of those boxes runs about $330 (from a quick price check on summit).

What we were going to make would be a module that had a VB program on it to retard timing to 3 seperate outputs based on boost and RPM. The PIC and hardware for that is well under $100... the big price comes in when you have to buy coils and ignitors... but I suppose you could just use some stock components... or I here the C5 coils are badass and contain the ignitor, but they run $50 a pop... just a thought.

 

Two FD ignitors should do the trick!
BTW. What's the deal with the factory 20B ignitor and coil pack?

crispeed
87 Rx-7 TII
9.204@150.47mph
2600lbs
un-tubbed

 

http://www.motec.com.au/drawings/m16.pdf
it wires up like an fd one, but im not sure if the signal is like an fc trailing, or like an fd. the 20b coil is like a ford coil, it has a b+ and one post for each rotor

mike

 

Weather I run split or simultainous will depend on where I buya house at and where I work God willing Ill be here at Lockheed and I can buy out in the country and not have to worry about emissions.

However, what kinda of power difference is ther between the 2 types???

 

Most people make more power without running split timing.... but, it is my understanding and belief that to do this, you have to have your engein tuned near perfection. The trailing is there primarily for emissions, and it improves on gas mileage at cruise. It also (shudder) provides a bit of fudge factor....

If you plan on running no split, then do research on spark plugs....

Oh yeah, I don't have to worry about emissions at all.... no sniffer test not visual inspection. nothing.

 

at least my smog test guy is blind....

mike

 

Mazda (stock) and their sponsored road racing teams (Downing Atlanta, Mandeville Auto Tech, etc.) make more power without the split. However, some of the people on this forum who drag race claim more power with the split. I guess it depends on how well you can tune.

Everyone agrees that the split will reduce emissions.

 

riceracing said when you fire the plugs without the split that the combustion happens faster. this would explain why it effects emissions, they want a slow complete burn. you know i should reread my silver rotary engine book it probably has a whole chapter about that.

mike

 

If higher octane gas slows the combustion process and should be used in forced induction engines, then so should the split, right? If so, then lower octane gas and 0º split should be run in NA engines, right? (I'll need to know this if I go NA on a 20B, since I'm building my own ignition system)

 

ok i looked thru the book but it doesn't specifically talk about firing the plugs together
rotary engine by kenichi yamamoto, 1981

"4.3 combustion characteristics
in the rotary engine, the working chamber is divided into leading and trailing sides by the minor axis in the of the top dead center in the copression-stroke. The trailing side is compressed, while the leading side is expanded. This will cause squish flow from the trailing side to the leading side for a long time. This strong squish flow will raitse the burning speed. While, the working chamber of flat and high surface/ volume ratio will result in lower burning speed. These two factors will compete with each other to bring about the cumbustion charachteristics uniquie to the rotary engine."

"4.3.1 flame propagation
fig 4.18 shows the results of investigation on flame propagation using several ion-gaps buried in the housing.
The squish flow carriesthe flame toward the leading side , causing much faster flame propagation to the leading side than to the trailing side. In the trailing side, the working chamber is further flattened after the top dead center in the combustion-stroke to strengthen
the quenching action due to the cooling of the wall, which further retards the flame propagation...."

"4.7 effect of ignition system
The rotary engine is charachterized by the squish flow that forces the flame to propagate faster in the leading direction and slower in the trailing direction.
Therefore, the combustioon speed in the entire working chamber depends greatly on the starting position of the flame propagation, hence the spark plug arrangement becomes important...."

so thats what he says but its not really how to make power its how to make driveability and emissions.

mike

 

Hmm, then when the eccentric shaft rotates 180º and fires the Leading plug again (in wasted spark mode on '86 and later RX-7s), the squish flow is further ignited - or something. It's just a bit harder to do this on a 20B (180º wasted spark). I wonder if it's even necessary for NA (for that matter FI - forced induction)?

 

the only way to do wasted spark on a 20b is to fire the leading and trailing together, unfortunatly kenechi doen't really talk about that (or maybe he is?) he is talking about the placement in the housings

mike

 

That was a little strange. Why did this thread pop up? Did somebody vote?

Anyway, I've decided to not hook up Trailing on my NA 20B (for now). It will have 0º and 180º sparks every 120º on the Leading plugs. That should take care of the squish flow.

 

talk about a blast from the past....

mike

 

Keep us posted on the progress. I'm interested in any solution to the swaybar problem, mounts I think I can handle making. Ive already had the 20B in the FC engine bay, mounted on FC brackets and mounts, but its simply too high and of course the pan hits the swaybar. I could really go for a custom swaybar to save me altering the pan.
As for the ignition delay box; that is something I also am working on using either a PIC or 68hc processor, but the problem is finding time to do the programming AND do the engineering work on the car.

Gary
New Zealand.

 

Microtech LTX12 has been able to do this for over 2 years.....

 

Update for this old thread: PFS is running at least one, if not more, 20B engines with the TECIII. The production of the AEM Race has been postponed indefinitely. The Haltech E11 and Wolf3DV4 Plus also claim split timing capability on a 3-rotor engine.

Well it would be nice if the existence of the LT models was known to the rest of the world prior to a few months ago. In fact, I believe that there is only one (unfinished) web site that even lists the LT models.

 

it would have been nice thats for sure!!

Jon has been flat out with a workshop move and hasnt had a chance to finish off his site yet, inbetween all that im at him to get his dyno installed so i can throw my car on there!

the new version of the microtech should be avaliable within 6 weeks to the public which will run a 4 rotor with full leading/trailing split, sequential injection, 16 outputs etc!!

this will also be compatable with the 13b/20b as well for more features than the current range of ecu's

Dale