Traction control
 

I searched the forum, and there are very few threads on this. The leading prodeuct is Racelogic, which works primarily by cutting fuel. I understand that this is undesirable in a boosted car, especially a rotary.

They do offer a system that cuts spark though, and I don't see anything wrong with that.

I saw that RICE RACING ordered a Racelogic unit, care to chime in with your advice on the matter?

Any input is appreciated.
thanks
ryan

My input? Don't use traction control.

My advice BUY IT !!!!

I have the latest race logic with digital adjuster installed in my SP and It's amazing, I have flat shift and launch control too.

I wrote my own cut tables based of how i know the injection system to work on the 13B and its different to the way race logic do it, I log maximum 43 knock on the PFC with TC on v's 37 TC off and this knock is only a result of the engine movement on the misfire not due to any combistion related knock.

I drive my car in one instance using the TC for a 50+km stretch in tricky conditions and i was on it for most of the way, it was unbelievable, the drive and traction where others had no chance to keep up, I have used it all up a few thousdand km's and tested the launch and flat shift........ Its hands down the most amazing thing you can put on your FD period.

I have one customer here who has my old race mill spec connect race logic unit and he races with it in hill climbs and swears that he would never race without it and also echo's its the single best thing he has ever put on his car.

The only headache is the install, to do it neet and professionlay takes time.

^ cutting fuel is the ONLY way to do this properly, dont listen to general internet opinions instead take your cues from people with expeience in this field. Race Logic have that, and i have the rotary specific application experience, even with non optimized cut tables the systems work totaly fine, my tables are just 100% adapted to the 4 injector 2 rotor platform.

the race logic will work and is proven to do so on rotaries, that is why i chose their system over using any other ECU's inbuilt system some of which you hear horror stories about, you will get no such thing with these people who's credentials in this field are beyond reproach.

excellent company to deal with too btw, i had a fault with mine (due to a power wire i hooked that I should not have on the digital adjuster harness) and they sent me my unit back with a complete new board even though i admited the mistake !

Awesome. . .thanks for the feedback RICE. I read through the other threads, but none that I found seemed to have what you just offered. A conclusive result.

This is awesome news. I've been in some other cars with Racelogic, and I know that it is a GREAT product. People really don't understand how well it works. It automatically makes you the BEST driver in the world by putting down the absolute maximum amount of power your tires can stick to the road.

Anyway, I wrote them an email yesterday about a system for my 3-rotor, so we'll see what they say back.

Out of curiousity, why do you say cutting fuel is the ONLY way to go? What is wrong with cutting spark in your opinion?

thanks
ryan

Fuel cut is the only way to go full stop, spark cut causes excessive wash out of oil in engine = greater wear, it drowns spark plugs, over heats turbo and exhaust, causes massive flames out tail pipe........ its ghetto really.

Race Logic may have my files, let me know who you talk with there, they did admit to my tables being more correct than their defults shipped for 2 rotor cars as they did not take into account sequential operation of injectors (I cut them in batches per rotor & alternate them to evenly distribute the pattern), not sure how they will go with 3 rotor, you will probably have to buy the more expensive system with more channels and they may have to write you some specific software for that application, i have not sat down to work that config out. It took me a few hours to double sheck all of my ticks and crosses and lay over the firing order to make sure I had no anomilies in mine.

Anyway make sure you get the launch control and flat shifting and the digital adjuster, I found that invaluable in my long distance test when road conditions changed and i could tweak it on the fly, makes you feel like a F1 driver !

Totaly awesome set up, with my brand new 850bhp engine combination it will come into its own ;)

What is "flat shift"?

with the addition of AI to the turbo rotary things become a major handful.

anything more than 450 rwhp and you are liable to be driving out of your side windows:)

in most gears.

that's what happens when you can run pump gas and AI. you can have all that hp all of the time.

which leads to the question: how the XXXX do you hook it up. as they say, power is nothing without control. sure you can go bigger tire-wise, you can run softer tires, you can run more rear weight. but what happens after you have done all that and are still sideways. especially when you are running 10-tenths.

Rice has the answer: Traction Control (TC).

it seems it is (yet) another need in the AI world we live in.

i haven't had any experience w TC to date although it will be something to consider as the year rolls on. i note that the AEM EMS has TC within it's bag of features. it has lots of define-ability within the TC so no doubt it may be possible to totally screw it up or perhaps make it work. i say perhaps as the jury seems to be still out as to whether the AEM EMS works properly. it is interesting though as once you have a proper reading on vehicle dynamics you have all you need to do TC. i am looking in to FJO's EMS currently. they do not have a rotary app at the moment but may have in the near future. perhaps they will include TC.

in the mean time Race Logic apparently has the answer along w Rice's programming.

TC is the way to go although my road racing instincts are crying foul-ball, but when you have more, in some cases alot more, than 450 rwhp on tap maybe it is time to make the right decision.

BTW, what's w the #2 post in this thread? TC not a "way to go?" everyone's entitled to their opinion, including #2, but we would be interested in the "why."

hc

RICE can correct me if I'm wrong, but a flat shift is an ability afforded by Racelogic's system.

What it is, is you keep your right foot on the floor, and when you clutch, it triggers a special rev limiter so that you don't have to lift, then when you let the clutch up, it goes back to the default settings. This allows for faster shifts, their website claims 0.1 seconds per shift faster in general.

I'll definitely keep updating this thread with any and all info I get my hands on.

I am also interested in the reccomendation for no traction control
ryan

^ flat shifting cuts the engine to its secondary limit (mine set at 5700rpm) so when you depress the clutch a switch shuts down engine via fuel cut and its just like lifting off accelerator except you have no reduced time to reopen throttle basicaly = faster acceleration through gears as throttle is always held at 100% opening, it takes a little while to stop your right foot from flinching (wanting to lift) but its amazing how it works and gear shifts are smoother and faster as there is no engine load and the load is diminished quicker with fuel cut rather than combination of downward slope of TPS, then MAP then injector signal etc etc etc its far more instantaneous and that is the mechanics behind why its far superior to use flat shifting even in a syncro street box.

The reason for not using TC is very valid on a rotary because most ECU have software written for individual injector cuts per cylinder and when adapted to the wankel they stuff motors very quickly if used in the ideal fuel cut mode v's spark cutting, for it to function correctly you need faith in the suppliers software/hardware and in Race Logic you have this even with their default cut settings. I dont like taking gambles and from what i have herd from others TC on most ECU's thats written for pistons does not work with rotaries, hence it has a bad name. RL have no such vices.

The other thing you need to realise with RL is its very advanced, they used to supply to F1 so need i say more? its fully tunable and it works as a fantastic add on to any ECU that has 4 injectors in a 2 rotor application, just for the feature of the digital adjuster to do triming while on track its another thing that makes this the proven system for the FD.

Right, I understood the idea of running a poorly functioning TC system being bad. . .I was just curious if %7C meant that he supposed one ought not run a fully functioning TC system, like the RL.

You brought up another advantage of the "flat shift" feature that I failed to spell out with perfect clarity. If you run a BOV, it won't open since your TB valving never closes causing vacuum to be drawn in your intake manifold. . .no need to wait for any respool after shifts, no matter where you are in the powerband.

I hope they get back to me today. I imagine this to be one of the best mods anyone could do to there high power car.

ryan

I run Racelogic's traction control on my 3rd gen and it is by far the greatest thing in the world. I love being able to keep my pedal to the floor through the corners. Its saved my ass numerous times. I also have the flat shit option and its great. If I bought another rwd sports car without traction control this would be my first upgrade for sure. Once you get it, youll wonder how you ever lived without it.

^^^On another note, I use the spark cut set up with no problem. And as for overheating the turbo and exhaust I have to ask RICE RACING if he has actually measured the temp difference between the spark cut and fuel cut set ups? let me know.

Not specificaly on the RL but on other cars yes, I have managed to get the whole exhaust system to glow red on a fairly std OEM car using spark rev limiter extensivley.

I remember others on here or another site talkinga bout plug fouling issues too but this I have not back to backed so its only passed on information.

Def agreed RL TC is the best mod you can make to the FD ;)

Here is the reply I got to my email.

Hi Ryan,

I'm afraid that we discontinued our spark cut system a while ago. It had
become commercially unviable so there really was no way we could
continue to sell it.

As far as injector cut is concerned, there are many RX7 owners who have
fitted the system with great success, although I am unable to say
whether or not it has been predominantly 2 or 3 rotor engines. However
I'd suggest checking out some rotary bulletin boards where I'm sure
information will be available.

Regards,

Mike Broadbent,
Sales Manager.


RACELOGIC Ltd
5 Little Balmer
Buckingham Ind.Pk.
MK18 1TF
TEL +44(1280) 823803 FAX +44(1280) 823595

mike.broadbent@racelogic.co.uk_www.racelogic.co.uk

Didn't instill alot of confidence in me with regards to product familiarity in so far as he didn't help me figure out which system I might need, but rather deferred me to a "rotary bulletin board". Who did you/should I try and talk to there RICE? Any chance I could get you to share your tables or share some info on how you tailored them? Without a copy of the RL software, I'm not exactly sure what you're talking about (obviously cutting fuel) and am just trying to get a clearer picture of exactly how this works.

Thanks a million
ryan

I run the RaceLogic w/ launch control and full throttle shift as well. It works very seamlessly. And although Mike isn't a RX-7 guy, he did supply me with a rotary-friendly DAT file. The fuel cut is the way to go as it does a complete cut so that it cannot even detonate...no fuel = no explosion.

First time it kicked in was during a wet autox...station workers kept commenting on misfire sounds (like in F1) but I felt nothing. Car just accelerated as ususal. The traction control in my other cars would lurch and buck in comparison.

Get the system, you won't regret it!

Well I've already decided on getting the system, nothing but hugely positive reviews. All I need is some help/advice on which system will suit my 3-rotors needs. Any and all advice is GREATLY appreciated.

thanks guys
ryan

RICE and Hedgehog, the communications I've had with RL to date have left me with some questions that I'm hoping you can clear up.

He says that the fuel cut method they use does NOT allow you to cut 2 injectors at once. How are you circumventinvg that issue given that we have both a primary AND a secondary injector on each rotor? Is cutting only the secondary adequate to prevent a lean detonation? What size are your primary and secondary injectors if this is the case and how are you staging them with your ECUs?

Thanks for the help guys, hoping to get this in my car soon.

ryan

The cut tables are in injector order, line order in wiring and in cycle batches on the cut tables, you can freely program them to what ever patterns you see fit & i do in a way that cuts primary & secondary for any given rotor.

The default way they program does NOT do it this way, its not a hard ware thing just a software table thing.

Either way its proven to work because even if you only cut one injector it makes the mixture that much leaner than what is *fireable* that it wont matter, you wont get a lean mixture ignition and potential knock that goes with it. I just prefered to cut my injectors in order of how they are sent from the ECU and it made a difference as I posted in the knock.

My original RL mill spec unit was sold through an Australian distributor (ChipTorque) as being specialy configured for a FD wankel 2 rotor 4 injector set up, upon my close analysis there was nothing of the sort in the injector cut sequence programming and RL admitted to me after i sent them my files that they (their current tech rep) did not realise the injectors were staged primary and secondary. In the end it does not matter technicaly but in the interests of total saftey I did my own custom cut tables that work fantasitcaly well.

I have one customer who runs the default and I run my own custom modified one. I have a manual time line chart that shows graphicaly the injector sequence as processed by the RL and what it does so am very sure of its end result :) took me many hours of checking and double checking to verify all of the "ticks" & "crosses" in the various stages of cut that the RL administers. The engine is smoother on my programming v's the RL one from my testing too & the knock level is nothing more than average realy ;)

In summary without me going to go get my manual full of notes the RL looks at the injector channels which are numbered & you just need to know how they work and cut them in batches alternating between front and rear rotor. each injector feeds two rotor faces in one firing cycle and depending on how the injector channels are wired to each rotor its these channels (or cylinders as RL call them) that you cut together, its just a matter of tallying them up to the rotors and their firing order. Probably have fully confused you now LOL :)

Mikes replies to me

"Hi Peter,

The file you sent me show the wheel speed signals as very noisy - was this log taken when you were driving on the road? If so you will need to eradicate the noise from these signals for the system to work properly.

In answer to your other email concerning injector cut, you are probably quite right. I had forgotten about the nature of the injector firing sequneces in the RX7 engine and if your evaulation leads you to have the cut sequences as you have them programmed now then that's how I'd leave it. Remember though, there is no cut fuel 'rate' coming from the TC ECU. It is a plain old CUT, that's it. The injector duty cycle is not altered, it is removed for one entire pulse. Given that you need about 80% of a normal fuel delivery to get any combustion at all, a 50% reduction will still produce a complete misfire.

Mike."

&

So, Lemme see If I got this straight. . .

I have a 3-rotor, as such I have 6 injectors. Let's call the injectors on rotor 1, 1 & 2, on rotor 2, 3 & 4, and on rotor 3, 5 & 6. The odd numbered injectors will be the primaries, although I don't think it matters.

1) The number assigned to each injector is dictated by how I connect them to the RL unit and nothing else, correct?

By my measure, the preffered mode to use with the RL unit is what they call the sequential mode in the RL Traction_Manual.pdf (LINK TO PAGE WITH MANUALS)

If my understanding is correct, the follwing sequences would work as follows.
Sequence 1 - 1st rotation it would cut both injectors on rotor 1, next rotation rotor 2, and next rotation rotor 3. Since the sequence isn't in multiples of 6, I am unsure if it would then start over with rotor 1 (if the sequence simply restarts), or if it would start over with rotor 2 (if the sequence is turned into an infinite continuous loop). Also, I photshopped this using the pictures in the manual, which is using the setting of cylinders =4, so this might not be what my sequence bars would looke like, either way, I think it can be illustrative for me.

Sequence 2 - It would cut both injectors to each rotor, starting with rotor 1, then rotor 3, then rotor 2, then rotor 1, then rotor 3.

Sequence 3 - cut both injectors to rotor 1 and 2, then rotors 2 and 3, then rotors 3 and 1.

http://img2.freeimagehosting.net/ima...c396c1a69d.jpg
CLICK HERE IF IMAGE DOESN'T WORK

What the hell are the integral settings?

I still have questions about how this would be implemented based on the order my Haltech fires the injectors in. . .Supposing it fires them sequentially, I would need my injectors wired from the haltech in the exact same manner as I described them to be wired to the RL unit, correct?

It says to start every sequence with a fire, but just tell me if I'm understanding it correctly please. . .it's kind of unclear to me.

Thanks again, hopefully I'm not way off in left field on this.
ryan

your on the right track.

the way the RL has the cut tables is that on 2 rotor its a odd number and so you dont get a totaly even rotation (but its close enough to not worry about), you just follow that pattern right through and on each level progresivley cut more and more cycles.

All the RL see's is injector signals and cuts them in order of how it sees them on each specified channel which correlates with the sequence in the cut tables, pretty basic but you really need to draw out a time cycle chart and then relate this to the RL tables and your most of the way to figuring it all out ;)

ok here is the detail !
 

This is the explination :)

Sequence table start with injector 1 (always fires with tick in box), the total number of boxes equals 5 firing cycles of the injectors (1,2,3,4) repeated 5 times, this starts with Front rotor and ends with Rear rotor.

Fr = 1&3 Injector
Rr = 2&4 Injector

The 4 levels of cut are set progresivly more, I do them 2/10, 4/10, 5/10, 7/10 and 10/10 for hard rev cut... this fraction = amount of cuts in 10 events as an expression.

With the above knowledge it does not matter if the ECU fires 1&3 or 2&4 together or in batched arrangement or ratio of staging as you will be cutting the injectors in pairs for each given cycle (1 to 4) repeated 5 times. All you have to do is alternate which rotor your deciding to cut to even the pattern out across the engine.

In sequential mode injectors are cut 1,2,3,4-1,2,3,4-1,2,3,4-1,2,3,4-1,2,3,4 and this is controled by either a tick or cross in the box which you can select. if injector 1&3 fire at the same time you will have as i understand it total injector cut if you have crosses in their matching box sections because the RL computer is looking for that channel through that wire as its hooked up.

fuel injector 1 = Fp = 4W (Lg/r) = RED wire pin 8 input
fuel injector 2 = Rp = 4Y (lg/b) = Orange wire pin 9 input
fuel injector 3 = Fs = 4X (Lg/w) = Grey wire pin 22 input
fuel injector 4 = Rs = 4Z (Lg) = Green wire pin 23 input

fuel injector firing order 1,2 or 1&3,2&4

Now the only thing that will fuck all of this up is if your saying RL told you in sequential mode the TC unit can only cut one channel at a time? I doubt that since it has multiple channel inputs and outputs to match the number of injectors, the only thing that is happening here is in our engines its seeing two injector channels at once and the way its looking up the cut sequence tables it cycles through all of these in the above liner fashion and must cut the respective injector line input as you have it programmed.

In practise after all of this theory and also with the copied e-mail I gave you the end is indeed smoother and the knock level is lower (in the testing I did).

3 rotor
 

For the 3 rotor then its as follows, each rotor is evenly spaced so it follows that firing order will be 1,2,3

injectors will be 1,2,3,4,5,6
R1 1&4
R2 2&5
R3 3&6

And you follow the above logic to apply it to the cut sequence tables. You will see it will cover 3 cycles with a portion left over *one rotor* from the 20 boxes you have to fill per sequence. For every 6 boxes I would group them F,M,R (front middle rear rotor) 1 to 6 injector and group the ticks and crosses so they match.

Thats basicaly how you do it. And now i am going to let my brain explode !

Just buy one !
 

In a V8 the firing order (which RL do as well) would mean that they are only cutting one piston at a time which I highly doubt as it would not reduce power quickly enough and also it totaly goes against how the hard cut rev table is set where it cuts all injector channels as they are recieved (all marked with crosses). if it did not work this way then the RL would get confused as to which injector is which in the firing sequence (this looks to me like it does not happen). Hope the above posts makes it a bit clearer for you and i have not confused you.

I dont see any technical reason why it wont work very well on a 3 rotor car IMHO they work on 4cyl, 6cyl and 8cyl reciprocating engines and have been proven to not fuck rotaries even when not programed the way I have mine set so you should feel pretty comfortable with that knowledge behind you.......... since we have done all of the experimentation LOL.

I think he does contradict himself where he says the RL wont allow you to cut 2 injectors at once because the most glaring fact against this is how the hard cut table is programmed and how it works, it cuts EVERY injector channel untill the RPM is stabilized/under the limit set (I.E. its VERY HARSH). In my car the SOFT rev limit alternates between front and rear rotor equaly and its a 50% cycle cut (v's 100% for hard cut) & this is VERY VERY SMOOTH when programmed my way V's there way which does not batch injectors together to match rotors (in 2 rotor car).