Anyone using Patrick's short G50 DME flywheel/clutch setup?

[Mike the mechanic]

I am wondering if anyone else is using Patrick Motorsports' short G50 DME flywheel/clutch set-up. I am having trouble getting the rpm/reference sensors adjusted correctly. It seems as though they have to be adjusted indpendently of each other, which is impossible with the stock bracket. The car is exhibiting a crazy miss/hesitation at low rpm. Hoping maybe someone had a similar experience and can help out.
Thanks!

[Mike the mechanic]

Anyone?

[ChrisBennet]

The stock 3.2 sensor bracket should hold both sensors in the correct location when the lower sensor is adjusted 0.8mm from the flywheel teeth. I don't know if that helps but I thought I mention it just in case...
Have you checked the sensor outputs with a 'scope?
-Chris

[Mike the mechanic]

Hi Chris, the Patrick Motorsports flywheel for shortened g50's is a little different than stock. It has the sensor ring very close to the engine case, and the actual reference sensor tdc pin is on the pressure plate. I was notified by Jim Patrick that I have to swap locations of the two sensors. Now, I have replaced both the rpm and reference sensors with new ones. (Are they both the same part number??) It seems that the reference pin is too far forward, and doesn't centre in the middle of the sensor when the rpm sensor is adjusted correctly. The only way i can make it run nicely is when the engine is running, I slide out he reference sensor. When it loses communication with the refernce pin, it seems to run better.
The funny thing is that before i got new sensors, the only way to make the car run well was to revert back to the original location of each sensor, meaning the rpm was on the reference pin and vice versa, but with that configuration, the car suffered the classic case of misadjusted rpm sensors. At anything over 3000rpm, the rpm guage started to move erratically and the engine missed.
I may have to remove the engine to compare the reference mark to the stock flywheel, but I want that to be my last resort!

[Mike the mechanic]

[ChrisBennet]

Mike,
They are the same sensor/part #.
It doesn't seem likely, but I've heard that the reference sensor is only "used" during starting.
Maybe you can shim the sensor bracket so the reference sensor end is angled out i.e. closer to centered on the pin.
I wonder if the pin itself is at the proper height?
-Chris

[dean]

Mike, Have you called Patrick yet? I know that would be painful but it might be helpful

[Mike the mechanic]

Dean, yes, I called Patrick, and he said that I should play with the angles, like Chris suggested. It's not working.
Chris, if you unplug the reference sensor while the car is running, the car continues to run fine, so it may be true about the reference sensor, BUT it wouldn't make sense in my case, where pulling out the sensor from it's holder makes the engine run better.
I will check the pin height as you suggested. If I knew how to attach an mpeg, I would post a small video clip of it running. Maybe that would help. I may be overlooking something stupid, which is usually the case, ie, overthinking.

[ChrisBennet]

Tonight I tried unplugging the reference sensor on my running 3.2. It idles and responded normally when I blipped the throttle confirming what I'd been told.
I think you really need to borrow a scope to see what that signal looks like.

-Chris

[Mike the mechanic]

I think you're right about getting a scope. The only thing is, I wouldn't know what to compare the signal to. By the way, I appreciate you taking the time to help.

[ChrisBennet]

Mike,
I haven't done this myself, but the factory manual shows what the signal should look like. I think it is -0.5 to 0.5v. You could adjust your sensor position to get the best signal that way.
It does strike me as a bit odd (micky mouse?) that Patrick's solution isn't "bolt on". It's one thing to design and debug something yourself but when you pay someone for a product you shouldn't have to finish the R&D for them.
-Chris

[1972_911T]

Did the issues with the patrickmotorsport short G50 flywheel/clutch kit for the 3.2 get sorted out? Im also looking at using a short G50 with my 3.2 conversion as an alternative to my mag 915. Has anyone actually got this conversion running satisfactory with the 3.2 DME?

Thanks Steve

[dean]

I don't think Patrick could solve the problem.

Give Dave at TRE a call. I think he has a solution.