Ralt RT5 FSV - Racetronic Fuel Injection - Need help

[RR98ITR]

Hi Everybody,
Does anyone have a manual or operating documentation for or other carnal knowledge of the Racetronic Electronic Fuel Injection setup as used on SCCA Pro Formula Super Vee RT5's back in the day?
I'm hustling to finish a down to the tub rebuild on my RT5 to make a race in 2 weeks and I have the Racetronic setup but no documentation. And while it's a pretty simple setup that I can figure out by experiment, I'm hoping that someone has knowledge that they're willing to share.
In particular, how is the Trigger wire setup? I'm using an MSD Electronic Ignition with crank trigger, but running the spark thru the VW distributors rotor and cap. The otherwise unused points are the logical Injection timing device - when Cyl-1 is firing spark at 36 degrees BTDC, Cyl-3 injector is pulsed at 36 degrees BBDC, etc. Is it as simple as running the trigger wire thru the points to ground?
Also, the Adjuster Screws, A and B, which is Low throttle and which is High throttle? A previous tuner has marked mine on the bottom with "A=1, B=5, at 2.2 bar". I would guess that A is low throttle, and B is high throttle, and that those are Turns OUT.
Can anyone help me?
Thanks,
Scott
RT5-321

[Lastminuteracin]

I too am in your situation. My Anson is still a ways off of running but engine management has been a question. I have the racetronic with the Bosch Lumination system but no distributor set up. I also have an Electromotive system that I believe I will use. Synching the two together is where I get all fuzzy. The racetronic seems to run off a 2 magnet aluminum crank rotor with the pick up built into the front crank seal carrier. It's "batch style" rather than "sequential" from my understanding. Where I get stumped is if I add the crank trigger wheel for the Electromotive will it get all screwed up by the 2 little magnets in the racetronic rotor? I would be surprised if the Racetronic will work with the later model 60-2 trigger wheels. At least not without a lot of reworking and programming.
Another Apex user sent me what documentation he had on the Racetronic. It was made by Zakspeed. It at least has some pin outs and such along with a description of A/B settings. Let me dig through my files and see where that info is and I'll send it to you. PM me your email please.
Jim White

[Lastminuteracin]

Actually right here on the forums
Racetronic ECU question (apexspeed.com)
Please let me know how you solve your problem
Thanks
Jim

[RR98ITR]

Hi Jim,
I saw that thread, but it doesn't hold the answers to my questions.
My car was originally equipped with a Lumenition Ignition, with an optical pickup and 2-"blade" rotor on the crank. The pickup wired back to the Lumenition box. It was all an insane tangle when I got the car.
Thanks,
Scott

[Lastminuteracin]

Sounds similar to the set up I got in my original box of parts. My mag pick up on the crank goes straight into the Bosch ign box too. What I don't have or understand is how to wire the trigger signal between the Bosh box and into the racetronic box. If I could get that handled I'd just buy a stock VW distributor and use it to just distribute the spark like yours. Someone out there knows. Finding them is the key. I've had little luck. Hopefully you can unlock the mystery.

[RR98ITR]

I'm reliably informed by excellent local tuner guy Doug, who has had his hands on several of these over the years, that the Racetronic is surprisingly simple in that every time it gets a signal it fires all 4 injectors simultaneously, and that the timing of the pulse with relation to exact crank position on the intake stroke makes no difference in horsepower, and that you piggyback the trigger wire onto the ignition signal wire. Misc stuff: you need some tension on the cable to ensure that the injectors fire at zero throttle/idle (and so too much and you're rich all the way up). I'll get this all sorted and confirmed and update this thread.
Scott

[teamwisconsin]

Sounds similar to the set up I got in my original box of parts. My mag pick up on the crank goes straight into the Bosch ign box too. What I don't have or understand is how to wire the trigger signal between the Bosh box and into the racetronic box. If I could get that handled I'd just buy a stock VW distributor and use it to just distribute the spark like yours. Someone out there knows. Finding them is the key. I've had little luck. Hopefully you can unlock the mystery.

I have Jennings distributors on the shelf for SuperVee application. They are all billet, use a Bosch cap, and wire directly to an MSD. If you’re interested ping me.

[Lastminuteracin]

May I ask if you found a solution? If so what was it? Thanks.

[RR98ITR]

After a lengthy and painful process, we have determined that the following combination works:

Running Both the MSD Digital-6 Plus Ignition AND the Racetronic Fuel Injection with a Pertronix ignitor in the Bosch distributor body.
Run the Ignition switch circuit thru the Pertronix, and out to the Triggers on the MSD AND the Racetronic.

We could NOT make the Racetronic run alone off the Pertronix, and think that the MSD's white "points" signal wire serves as a ballast resistor allowing the Pertronix to switch properly. All that nice machine work on the crank trigger wheel and pickup mount was for nothing.

Still don't know details about tuning with the Racetronic cable tension vs the A & B screws, or which screw is which but will eventually screw around with them and figure it out. Would Love to hear from somebody who knows about the Racetronic and has taken one apart.

The painful part - attempting to run the Racetronic off the MSD's tach output resulted in the rev limiter activating prematurely at 5500 and the tach quickly sweeping to the set (higher) rev limit and waggling there. NOTHING worked to rectify this over the course of a 5 session race weekend.

Scott

[reynard55]

I got this when I bought my RT5
To be honest I could not really make sense of it. You may be better

[RR98ITR]

Thank You Very Much Russ - that's very helpful

I got this when I bought my RT5
To be honest I could not really make sense of it. You may be better

[Lastminuteracin]

I got this when I bought my RT5
To be honest I could not really make sense of it. You may be better

Thank you very much. The more of this I can get the more the puzzle becomes clearer.

[Lastminuteracin]

Lets say I switched my Bosch system over to an Electromotive HP1 direct fire system. Does anyone know if I could use the tach signal wire from the HP1 to trigger the Racetronic injection box?

[SV@RHC]

I have a spare Electromotive. Ignition/fuel injection system. with Display off my Ralt RT5. even have the original manual. Let me know if you would like it $100 plus shipping?

Scott
(925) 493-9257

[reynard55]

Scott
You have a PM