distributor?
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sportd-fifty
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distributor?
Were there any dohc heads that had a distributor instead of the coil pack?The reason I ask is because the sohc head on my d50 is toast and I cant afford the whole conversion yet. I can fab up some carb mounts and use carbs off a motorcycle..gsxr. Also is there a good crank trigger system that I can use if I have to use the coil packs?
rock and roll
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DJpowerHaus
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None.. and if they did, it'd have to come out the back of the head. You could always find a way to put a distributer onto the front of the cam gears. Stranger things have been done.

Getting the engine bolted in is about 10% of the way there.
The next 80% can go quickly with help and skill.
That last 10% takes about as long as the 90% that came before it.
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sportd-fifty
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DJpowerHaus
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We checked my trigger signals coming form the CAS and the signals were exceptional. No noise at all. Luckily the Autronic takes the DSM CAS signal, not sure what other systems can use it.
I could have... and might in the future use a trigger wheel on the front. This along with a front water outlet will elminate the need for firewall modifications.
What's preventing you from getting a DSM harness, ECU and such? You could probably find a whole DSM for $100 with all the donor parts you need. What am I saying. This stuff gets expensive faster than you'd think.
I could have... and might in the future use a trigger wheel on the front. This along with a front water outlet will elminate the need for firewall modifications.
What's preventing you from getting a DSM harness, ECU and such? You could probably find a whole DSM for $100 with all the donor parts you need. What am I saying. This stuff gets expensive faster than you'd think.

Getting the engine bolted in is about 10% of the way there.
The next 80% can go quickly with help and skill.
That last 10% takes about as long as the 90% that came before it.
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sportd-fifty
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DJpowerHaus
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Basicly its this little hockey puck looking thing on the back of the head. Earlier years had an optical sensor that would shine an ultra violet LED onto a sensor through little slots on a rotating disk. There were 2 sensors, one for the cam rotation and a simulated signal for the revolutions of the crank. Not quite sure about all the details, but basicly this is how an engine without a distributer knows what speed the engine is spinning.
So.. you'll need an ECU that can minimum recognize the CAS signal and output a signal to fire 2 channels for a wasted spark system or 4 channels for a non-wasted spark setup.
Since very few ECUs can take this cam signal (OEM ECU, Autronic, AEM.. maybe a few others) you might as well set it up with a trigger wheel on the crank pulley (or flywheel if you're crafty)... or maybe use the balance shaft sprocket or make one with the proper number of teeth.. now that would be a nice clean way to do it with minimal chance of it getting hit by something since it'll be under the timing cover. Actually.... haha.. brainstorming as we go along here. The factory has a spacer to eliminate the balance shaft sprocket. It would be pretty easy to design and laser cut a trigger wheel that would mount to this.
On that note.. I don't think you'll be able to swap the head without going through with the rest of the swap.
So.. you'll need an ECU that can minimum recognize the CAS signal and output a signal to fire 2 channels for a wasted spark system or 4 channels for a non-wasted spark setup.
Since very few ECUs can take this cam signal (OEM ECU, Autronic, AEM.. maybe a few others) you might as well set it up with a trigger wheel on the crank pulley (or flywheel if you're crafty)... or maybe use the balance shaft sprocket or make one with the proper number of teeth.. now that would be a nice clean way to do it with minimal chance of it getting hit by something since it'll be under the timing cover. Actually.... haha.. brainstorming as we go along here. The factory has a spacer to eliminate the balance shaft sprocket. It would be pretty easy to design and laser cut a trigger wheel that would mount to this.
On that note.. I don't think you'll be able to swap the head without going through with the rest of the swap.

Getting the engine bolted in is about 10% of the way there.
The next 80% can go quickly with help and skill.
That last 10% takes about as long as the 90% that came before it.
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sportd-fifty
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yeah you said what I was loathing to hear. The factory ecm prob the only thing that I could use to get this thing running...on the cheap. Aem units cost as much as the entire parts car that im hoping to buy. The motorcycle carb thing was my last hope. oh well time to go backyard hunting. Im also waiting to get my manuals in so I can do some wire chasing on my truck.Any other ideas tips hints would be appreciated guys thanks
rock and roll
When I have some time I will be designing a new timing wheel that goes into the standard gen 1 cas so that it can be relocated to the front of the head and use the factory computer. I had hoped that the Mitsubishi made cas that is fitted to the front of some Nissan motors had the required modifications, but saddly the timing wheel is very different.
I have seen a 4g63 dohc with twin weber sidedraft carbs with custom manifold using a MSD ignition system.
Dave
I have seen a 4g63 dohc with twin weber sidedraft carbs with custom manifold using a MSD ignition system.
Dave
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sportd-fifty
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DJpowerHaus
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They produce a square wave: http://roadraceengineering.com/1gcasin2g-waveforms.htm
More info here:
http://roadraceengineering.com/1gcasin2g.htm
More info here:
http://roadraceengineering.com/1gcasin2g.htm

Getting the engine bolted in is about 10% of the way there.
The next 80% can go quickly with help and skill.
That last 10% takes about as long as the 90% that came before it.