EFI Trigger Wheels

[Ferrino]

Has anyone installed an aftermarket 36-1/60-2 trigger wheel (and sensor) without going distributorless right away? If so, can you please share how you mounted your sensor?

I know a lot of folks use the Rothsport sensor bracket, but I understand that involves losing the dizzy as it uses the same stud. I'd like to keep my dizzy for the 1st round of EFI with ITBs, to do things incrementally, and switch to wasted-spark later...

Thanks!

[rsscotty]

The Rothsport mount can be used with the distributor in place.... we use a longer stud in the case. We also designed it to be used with a specific Mercedes ref. sensor.

[Raceboy]

Will be in the same situation shortly. I made a custom twin-plug distributor which will house a cam sync but crank sensor placement is open at the moment. Either to distributor stud or to other side, onto engine mount bolts.

[al lkosmal]

It is smart to make one change at a time, but why mount the sensor if you are going to use the dizzy 1st? Just mount the trigger wheel now and mount the sensor later, when you're ready to ditch the dizzy and go wasted spark.

regards,
al

[Ferrino]

Originally Posted by al lkosmal

It is smart to make one change at a time, but why mount the sensor if you are going to use the dizzy 1st? Just mount the trigger wheel now and mount the sensor later, when you're ready to ditch the dizzy and go wasted spark.

Not sure I follow. I am planning to install ITBs with an ECU that uses a trigger wheel for timing. If I keep my Carrera coil/dizzy for ignition, I still need to mount the trigger wheel sensor in order for the ECU to function.

[prschmn]

If you're doing this on a 3.0 or 3.2 with a 915 why not use a 60-2 flywheel? Patrick makes one
and I have an almost new one I don't need. Not hard to mount a sensor.

[darud35]

I have a product that will do both cam and crank through your distributor. No need for separate sensors. Works with any ECU that accepts a hall effect sensor.

Porsche 911 Distributor EPM Adapter Kit - Rasant Products

[al lkosmal]

Originally Posted by Ferrino

Not sure I follow. I am planning to install ITBs with an ECU that uses a trigger wheel for timing. If I keep my Carrera coil/dizzy for ignition, I still need to mount the trigger wheel sensor in order for the ECU to function.

Ahhh. I see now. Since you were keeping the stock dizzy, i thought you might be using the tach signal to the ECU to get the engine fired up and the EFI dialed in and then later going to change the ignition to crank trigger/wasted spark.

regards,
al

PS: I've used the Rasant products system, including the dizzy mod with cam and crank sensor capability and ......it works great. I highly recommend it.

[Ferrino]

Thanks for all the suggestions. One of the reasons I don't want to switch out the flywheel or modify the dizzy is because I want it to be easily reversible (i.e. back to the stock Motronic configuration).

Darud: I've been following your EFI thread and I believe I saw your car at Luftgekuhlt recently: lovely bit of kit!

[darud35]

Thanks Al!

Ferrino, I may have a spare dizzy if you want to keep yours in original condition to easily revert to stock. Difficult to do EFI/ignition control incrementally this way though.

What ECU are you planning on running out of curiosity?

[Ferrino]

Thanks for the tips. I've ordered a 36-1 wheel for the crank pulley. I'm not sure if I will use the sensor bracket that uses the dizzy stud or just fabricate my own as I am torn between a VR sensor and a threaded Hall sensor. It would be nice to not have to tweak the sensor depending on the presence/absence of dizzy.

What ECU are you planning on running out of curiosity?

After much deliberation, I'm going with the Microsquirt. It appears to meet all my needs: price, compact & weatherproof case/connector, batch injection, 6-cylinder wasted-spark, excellent support from DIYAutoTune, documentation, external MAP sensor... If I ever have a need for sequential injection some day, I figure this will give me an excellent introduction to EFI.

[jpnovak]

I use a hall effect sensor that is mounted to the fan web on the case behind the pulley. The stock pulley is drilled for trigger magnets. This setup is highly discrete and only has a small 3 wire harness going to it. Mounting requires two M3 holes drilled and tapped. This provides the use of an ECU to control timing but with the visual looks of a distributor.

In fact, I am installing a microsquirt system right now with the same pickup. Its a 74 with a warmed over 3.0. Getting ITBs and full electronic engine management but trying to keep a vintage aesthetic. Yes, the motor is twin plug and the distributor is an important visual marker to the engine.

[Ferrino]

Thanks Jamie. I was actually proposing to use a Hall sensor with the internal magnet (reading the ferrous teeth on the trigger wheel). I'd love to see your magnet-on-pulley setup, out of curiosity. Do you have any pics of where you tapped into the "fan web"?

I'm not as attached to the dizzy for a vintage look - I figure 6 honking great velocity stacks will suffice. I was planning to run 6 "smart" COPs in wasted-spark mode. I am not sure if the Microsquirt will drive a pair of smart COPs per 5V spark channel - was told in depends on their resistance. I will measure when they arrive...