Rabbit Farmer's various VW Projects

[Rabbit Farmer]

Turbo Rabbit update.... still not running properly. Need to look at epoxy thing on back of tach, FPR, and coils. Hmmm, how about looking at the timing first.

[sdwarf36]

sell the whole car now and start on my Subaru racer instead.

SAY WHAT??

[Rabbit Farmer]

Not quite ready for that yet. Need to pay off the truck and car (Julie's) before I dive into any other projects.

[Rabbit Farmer]

Tonight I finished mapping out the wires, vacuum lines, fuel lines, and air under the hood..... pretty much got everything to the firewall on both sides (under the hood and inside the car) now I just need to connect it all together.

Pictures of some of the parts to give you a clearer idea of what I am looking at...

Microfueler


The dash (switch panel flipped forward to access the harness)


Coils


Close up of adjustments at end of coils


What the...?????


Charlie, Steve, & Joey installing transmission after 3rd gear went (in time for Burke)

[Rabbit Farmer]

Oh, and I did check the mechanical timing.
Cams up (valves closed) and piston is all the way up. TDC.
The distributor is about 5 teeth from the firing point, but I don't know if it is advanced or retarded as I'm unsure which way the engine rotates (used to be able to figure out based on the spark plug wires, but this doesn't have any. Comparing to a clock, 12 is pointing at the engine block, 6 at the front of the car.... 4 is a firing position (1 of 2 of them... the other is 180-degrees from there) and the magnetic pickup is pointing five teeth before (i.e. 3:55).

So, if this rotates clockwise, the firing is ADVANCED by five teeth on the wheel (I believe this is how it is) or if it rotates counter-clockwise then it is RETARDED five teeth. I believe it rotates clockwise.

So, based on this (assuming I have it all figured out correctly) the mechanical timing (piston/crank and valves/cam) is good and the ignition timing is 5 teeth (unsure of degrees) advanced.

Tells me that the timing did not change.

Steve

[walterclark]

Ah, this is a distributor-less conversion - or more accurately it has an electronic distributor.

So if I get the pictures and description (those wiring diagrams make my brain hurt), it looks like the mechanical distributor is just used to define 0 for the electronic distributor, sort of like a crank sensor would be used on a modern distributor-less engine, except this one is adjustable. BTW, the distributor on the 8V does rotate CW. Try putting an inductive timing light on plug 1 wire and compare that to the flywheel reference mark to get an idea what your advance is. A big cammed, ported 8V can use up to 38 degrees advance at rpm above 3500 RPM but I am not sure what a turbo needs. probably less. Maybe someone with a MS graph for a turbo 8V posted on the internet somewhere for reference.

Oh. Since the coils are part of an electronic distributor, and it it looks like the green wire (tach) goes into the control module on the coil board (it looks like the other green wire, terminated under a case screw on the one coil, is a ground) it is likely the signal on this wire is the eqivilant to an "electronic tach" signal from an ECU which will be lower in peak amplitude and much cleaner than a coil - tach signal. It looks like it was tapped into on the potted control board and not part of the original Electromotive design. It is also possible the point that was tapped into was not buffered well enough to drive an external load like a tach so the magneto adapter was added to prevent the VDO tach from loading or distorting the signal in the module and messing up the distributor.

I found this manual online for the HPV-1: http://electromotive-inc.com/pdf_files/hpv1.pdf It does identify a signal brought out to the HPV-1 connector called TAC and it instructs you to attach an external tachometer to this but only in the context of also having their optional rev limiter installed so it is not clear to me that this is an output from the HPV-1 but it only makes sense that it is. If that terminal is what your green tach wire is connected to then the tach should be set up as "electronic".

[Rabbit Farmer]

Well.... back from Ascutney. Transmission held together, but I was babying it. I didn't want to discover (naturally, afterwards) what the limit of the gears were again as I need to make it last the rest of the season. My laptop (or the software) could not see the 034EFI ECU to turn down the boost so I had to use my foot/brain to ensure that max power was not delivered to the gears. Ascutney hillclimb is a bit rough up top so I make sure to get very careful not to get wheel spin/hop. First run up the hill was a 3:19 (VERY slow... my best in the past with this car was a 2:58), then a 3:03, and a 3:06.

I set up some rules (for me) with each run.

3:19 was no more than 1/2 throttle ever, no more than 4500 RPM, coast it through all sharp corners where the LSD would normally be working, and run in 3rd gear above checkpoint 7 (top of the hill) as it is rough. Very slow time, but had to feel things out.

3:03 was 1/2 throttle with no max RPM, all other rules apply.

3:06 was 3/4 with max of 4500 RPM, all other rules apply.

On Sunday I worked with 3/4+ throttle with no max RPM for a 3:03, 2:58 and a 3:00 (main rule was not to make the LSD work in the sharp corners and limit the wheel spin). Not the fastest times, but I didn't want to risk breaking it. I would rather driver slower than have to fix it again.

Charlie (Volvo) is threaten to help me get the Tub II fixed. If it is, it will be at Philo.

Steve

[Rabbit Farmer]

Progress?

John is almost done with the transmission.

I have been doing more research on the Electromotive Direct Ignition (HPV-1) setup on the turbo Rabbit (aka Tub II). There is a lot of good information in the manual.... a lot of reading. I'm also sourcing a new set of coils.

http://www.directignition.com/pdf_files/hpv1.pdf

(sign) I really want to get the turbo Rabbit going again as I am soooo addicted to the 5 gears on the hill.

Steve

[Rabbit Farmer]

Speaking with a guy today that actually knows the type of ignition system on the Tub II, he doesn't think it is the coils. He wants me to look at the coil drivers (I don't know what those are), the battery, and the alternator. Due to the high voltage that these suckers put out, there is a possibility that they are overwhelming the car's ability to deliver the power. Of course, last summer I started using a light weight gel battery (though, I have been using all summer), so that might play into it somehow.

There is a lot of interesting information on the setup of the electronic ignition in the manual so I have a bit of troubleshooting to do.

[Rabbit Farmer]

Picked up 6-speed from Fast Addiction; everything looks great.

6-speed (now with LSD)
6-speed axles, hubs, starter, shift box/cables, power steering line, and hydraulic clutch line.





Add in the Spec 2+ clutch and lightened flywheel (interesting design)....


...means that the stock clutch, flywheel, and differiential for the 6-speed are for sale.
(I also have a stock 5-speed diff and 5th gear for sale)