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Re: 36-1 Crank Wheels

Posted: Mon Jul 12, 2010 3:01 am
by aphesis
Looks the goods, came up looking very neat.

Just wondering if you also play around with the Holden 6, I noticed you said earlier you had some wheels cut to suit this. If so do you have a photo of it mounted to a Holden 6?

Thanks

Re: 36-1 Crank Wheels

Posted: Wed Jul 14, 2010 4:00 pm
by long283
Yes, i have a Holden Six blue/black motor with the VK EFI manifold and a Haltec EFI computer.
I hope to get one of the 36-1 wheels on that but it may take a few months because it is on the other side of the country.
I'm also hoping to try one of the 7" wheels on a Valiant slant-motor just for laughs.

PM me if you are interested and I can send you a link with more of the six-cylinder details.

Re: 36-1 Crank Wheels

Posted: Thu Jul 15, 2010 1:32 am
by wagon
Looks very neat Long283. Good stuff!

Where and how did you mount the pickup?

Re: 36-1 Crank Wheels

Posted: Sun Jul 18, 2010 2:21 pm
by long283
The pick-up mount is in progress I'll put some photos up when I get in on. I'm trying to make a bracket for this gear-tooth sensor http://au.farnell.com/allegro-microsyst ... tt=1278528 so I can have a square wave output. If that doesn't work I'll use a VR sensor like this one http://www.injectacarb.com.au/ford-falc ... -p-57.html.

I tested the welded nut and it works quite well for turning the engine over while I set the rocker pre-load (with the spark plugs out of course). And I couldn't get my dial gauge in but using a steel rule clamped in place the 36-1 wheel had much less than 0.5mm run-out using the three mounting bolts.

Photos coming as soon as I finish the bracket.

Re: 36-1 Crank Wheels

Posted: Mon Aug 09, 2010 3:55 am
by long283
I've made up a bracket for the C.A.S. from a few scrap bits of aluminium

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I just need to solder a 0.1uF capacitor and the wires to the sensor then epoxy them in the aluminium blocks. The wires will go through the block and come out the back.

Image

This should give me enough adjustment to line the sensor up with the 36-1 wheel.

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More photos to come when it is installed on the car (and tested) soon.

Re: 36-1 Crank Wheels

Posted: Tue Aug 10, 2010 2:56 am
by devojet
Nice looking brackets!!

I'm interested to see how that sensor goes.

Cheers

Daniel.

Re: 36-1 Crank Wheels

Posted: Sat Aug 21, 2010 4:38 pm
by long283
I managed to get the bracket installed last weekend but I'm still playing with the settings to get it working properly. I've plugged the distributor sensor back in to keep it running for now.
I used my oscilloscope to check the signal and the output looks good, I am going to get a licence for TunerStudio ( will need that for the semi-sequential settings anyway) so I can use the trigger logger to diagnose what is happening.

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Re: 36-1 Crank Wheels

Posted: Wed Sep 29, 2010 2:27 pm
by long283
Sorry about the lack of updates. i haven't had much time to troubleshoot the CAS recently.
I did grab one of these sensors
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http://au.farnell.com/honeywell-s-c/1gt ... dp/1225630 and need to make a bracket for it.

I think the other sensors I have should be ok but I will remake the housing for them out of nylon or a similar non-metalic material.

Re: 36-1 Crank Wheels

Posted: Tue Apr 12, 2011 2:51 pm
by long283
Ok, It's been a while since I updated my progress on converting to CAS but I finally seem to be getting somewhere.

I found I have been getting a good signal from the 1GT101DC sensor as I was with the previous sensor but have had a great deal of frustration with the tach input circuit on the MS2.
After finding that the opto-coupler circuit didn't seem to respond fast enough to work with a 36-1 crank angle sensor I switched to the VR input circuit. This still didn't work so I have been carrying out a lot of bench testing and reading of the manuals & forums :RTFM: .
I found that a lot of other users have had trouble using the VR circuit with missing tooth wheels and even after adjusting the trim pots R52 & R56 I still couldn't get the MS2 to go above ~3000rpm using a JimStim. The next thing I did was remove the dual opamp U7 and put in a 8pin DIP socket to try a different opamp. I used a Microchip part that was recommended in one of the forums and still couldn't get the MS2 to stay in sinc at rpms above idle (~950rpm).
Further reading of the forums revealed that building a VR conditioning circuit using a LM1815N chip works better...
but I was fed up with using the sub standard MS2 VR circuit (although it is quite adequate for other evenly spaced triggers) and since I was using a hall-effect sensor which outputs a nice squarewave I found what I thought was a better option.

I made a simple transistor buffered input circuit that is much like the opto-coupler circuit but uses a transistor in place of the opto-coupler. The opto-coupler was designed when MS1 was being used as a fuel only computer and was detecting a high voltage trigger from the coil, this protected the micro-controller from being damaged by a high voltage spike. The hall-input I am using is an open collector with a 5-12v pull-up resistor and does not need that much protection. A diode from the input pin to Vcc after R12 would protect from small spikes.

I have tried out this mod on the bench top and it worked perfectly, all the way to 16000rpm using a JimStim and the 36-1 setting.
I will try it on the car shortly and posts some pics up.

Re: 36-1 Crank Wheels

Posted: Tue Apr 12, 2011 6:12 pm
by devojet
I have also found that the standard VR circuit works great with non miss tooth wheels, but can have troubles with miss tooth wheels. The EF falcon I had had troubles with the 36-1 wheel. I had to change some of the capacitor values in the vr circuit to make it rev above 1200rpm.

Your new hall effect circuit sounds like the way to go.

Cheers

Daniel.