VR signal from pulley modified with holes for trigger

Alexander_Monday · Post by **Alexander_Monday** » Tue Sep 16, 2008 12:43 pm

I modified an aftermarket VW pulley with holes instead of teeth.
The VR signal looks good to me, just wanted to see if I am correct?
Also, what voltage peak to peak should I shoot for when I space the
pickup from the pulley?
Pardon the blurry picture, I was holding the camera in one hand and
a cordless drill with the pulley in the other and the camera caught
several retraces during exposure.

DannyP · Post by **DannyP** » Thu Sep 18, 2008 2:39 am

Looks good, the trace looks nice and clean. I have a type1 map that is set up for TPS. It works very well, so you are welcome to it. It is posted here on this site.

Alexander_Monday · Post by **Alexander_Monday** » Thu Sep 18, 2008 12:15 pm

Thank you, but I will be using MAP because this will be a boosted engine.
It will be NA for a while, until DLI comes through with the supercharger.
I hope to have it on the road again within a month, assuming Berg gets
me the custom order spacers I am waiting on.

Guess I will just experiment with the VR Peak-Peak voltage to see what works good.
Since I have not found a definitive answer to what the factory P-P voltage should be,
I was thinking of putting a variable attenuator in the line temporarily to see at what
voltage it drops out, then increase from there.

MartinM · Post by **MartinM** » Thu Sep 18, 2008 10:04 pm

Very nice lateral thinking there

... and nice waveform - looks like you've got it running very concentrically

Can't exactly remember what I measured on a normal toothed wheel - in the region of 1.5v - 20v pk-to-pk (higher rpm = higher voltage) IIRC

I don't think you need an attenuator - you're not going to find your metal between the holes suddenly producing e.g. 2x the voltage that a normal wheel produces.

Ford use/used all sorts of wheels - from bent tin plate to webbed spokes on flywheels and as far as I know, they didn't use different EDIS's depending on the trigger wheel construction

I'm impressed - and it's given me a few ideas ... thanks for the posting!

Alexander_Monday · Post by **Alexander_Monday** » Thu Sep 18, 2008 10:32 pm

MartinM, Thank you.

Since this is different than factory I do not know what spacing to use from the VR to the wheel.
The attenuator was to find out at what point the signal no longer works so I would have a
reference to go by to space out the VR where I had about double the minimum. I have been
called anal many times, so maybe I am just over thinking it.

Wish I would have over thought the placement of my VR before I drilled the missing tooth out.
I have trapped the alternator / fan belt and will have to remove the VR to put a new one on.

Oh well, live and learn.

MartinM · Post by **MartinM** » Thu Sep 18, 2008 10:37 pm

Alexander_Monday wrote:I have trapped the alternator / fan belt and will have to remove the VR to put a new one on. Oh well, live and learn.

Don't think that you're the first person to do that -

as well here!

I'd just set it up normally - 1-2mm should be easy given that it looks highly concentric - and see how it goes in practice....you're not going to break anything IMHO

DannyP · Post by **DannyP** » Fri Sep 19, 2008 1:43 am

Alexander, that's why I put mine near the TDC mark on the case. All I have to do is unplug the VR sensor.

Alexander_Monday · Post by **Alexander_Monday** » Wed Oct 15, 2008 8:34 pm

There was no way to change the location of the "missing tooth" now, so I have
machined a second keyway into the pulley at 130 degrees from the stock location.
This puts the VR sensor between the belt like the picture above.

I was hoping to get it going this last weekend, however made a terrible mistake
when wiring the rev limiter board to the processor board. Long story short, I
fried the processor and the clock. In the process of ordering new ones so when
they arrive, assuming I don't make anymore mistakes, will get it going.

Alexander_Monday · Post by **Alexander_Monday** » Tue Oct 21, 2008 3:24 am

Just got MJ going tonight, and the modified pulley with holes instead of teeth works great.

NITROPIXIE · Post by **NITROPIXIE** » Tue Oct 21, 2008 9:06 am

great news, opens the window for more possibilities of trigger wheel

david_594 · Post by **david_594** » Sat Nov 01, 2008 3:12 am

What type of pulley is that? Or where did you get it?

Never seen one with a thick surface like that before.

DannyP · Post by **DannyP** » Sat Nov 01, 2008 11:25 am

It might be a Gene Berg Equalizer, big heavy steel. A harmonic balancer for VW, kind of offsets the lightweight flywheel most use.

david_594 · Post by **david_594** » Sat Nov 01, 2008 6:27 pm

DannyP wrote:It might be a Gene Berg Equalizer, big heavy steel. A harmonic balancer for VW, kind of offsets the lightweight flywheel most use.

Thanks, I figure it out kind of after the fact. I think i am going to get one(cheaper one) for my vw and drill it out the same way.

It would be for my 68 bus with an otherwise bone stock 1600 dp motor. I figure the extra weight can only help in my application.

DannyP · Post by **DannyP** » Sun Nov 02, 2008 12:12 pm

BTW Alexander, excellent thinking on the holes. I had pondered 35 holes in an aluminum pulley filled with threaded plugs, but in the end the stock EDIS pulley worked well, much modified. I like the Berg pulley idea. What thickness and cylinder bore are the spacers? There are many other sources, aircooled.net, SCAT, evwparts, etc. I have stacked spacers on my engine as I didn't want to wait for custom cut spacers. No problem at all.

Alexander_Monday · Post by **Alexander_Monday** » Mon Nov 03, 2008 1:27 pm

DannyP wrote:It might be a Gene Berg Equalizer, big heavy steel. A harmonic balancer for VW, kind of offsets the lightweight flywheel most use.

Indeed, it is a Berg Equalizer pulley.

DannyP wrote:BTW Alexander, excellent thinking on the holes. I had pondered 35 holes in an aluminum pulley filled with threaded plugs, but in the end the stock EDIS pulley worked well, much modified. I like the Berg pulley idea. What thickness and cylinder bore are the spacers? There are many other sources, aircooled.net, SCAT, evwparts, etc. I have stacked spacers on my engine as I didn't want to wait for custom cut spacers. No problem at all.

Spacers are in and installed. Old 90.5 case bore. The cylinders are thick wall 90.5's that I had the case side of them machined to the old thin wall 90.5 bore to retain more strength for 10mm case savers. I needed .070 which is an odd thickness not to mention that no one carries the old thin wall stuff anymore.

Seems that this engine just wants to give me no end of grief. The latest development with it is that the Weber IDF's have decided at random to fill over and flood the engine. The first time it did it while sitting, and I lifted the passenger side head when I started it due to hydraulic lock. Fortunately the case was not harmed. Fixed it, and took that carb apart. Found nothing wrong with it. Decided to put a switch on the electric fuel pump and let the carbs run dry when I shut it off as a safety measure. Was driving yesterday, and the A/F went in the toilet and it started missing. Pulled over and checked the carbs, and the drivers carb was running over and filled the intake ports. Towed it home. The good news was that both of those intake valves were shut. The odds of that happening at any random shut off are not very high, so I got lucky. Took off the carbs, used paper towels to remove the gas from the intake runners, removed plugs, turned over with starter to get any gas remaining flushed out. I am going to put a little oil in the cylinders, turn it over, and bag it for now. I am not going to try those carbs again, besides this is a fair weather car and winter is almost here in the Midwest. When I get the supercharger I will be able to use my new Holley carb, so I don't want to invest any more time or money into them.