1970's Hitachi Distributor Prep?

don-f

don-f

Well-known member
I am slowly working on a 1970s Civic that was a tub based GT class car in the 1980s, but is more suited to vintage racing now. I contacted a few vintage groups as I am putting things back together and all seem to want the crank trigger ignition gone. That is fine, but since I was told that the Datsun 1200's used almost the same Hitachi distributor, I was wondering if there was any suggestions on how the Datsun 1200 distributors were prepped? I can delete the vacuum advance pretty easily, but is it also advisable to lockout the centrifugal advance? I know its not the same car, but I was thinking the Datsun advice for making the old distributors work may be a good starting point to try for now.

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Its just they seem like a very econo box piece with a very small cap diameter and 40 years of wear probably doesn't help. Mostly they look like a good candidate for the trash can. I see why the crank trigger was the better alternative. I was hoping someone had some experience they could share on prepping the Hitachi made distributor, even if it was in a Datsun. If not I can make new bushings and try to tighten up the slop in the centrifugal advance for starters, or lock it out and use a switch to kill the spark until its spinning. Still not ideal, I know.

Some have adapted a VW distributor to the end of the camshaft, but finding information on this is hard. Most people that used to race them seem to have moved on or passed away. The one picture I do have of the Vw distributor drive welded to the end of the fuel pump lobe does not look that trouble free. So I decided to just try to prep the stock Hitachi for now.

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I find that I have to limit the mechanical advance to about 7-10 degrees measured at th dizzy. I usually weld the stop or weight.
This allows cranking at 6-10 BTDC and runs at 31-33 total. The electrical trigger system tolerates a lot of bushing slop and I seldom repair that bushing. The vacuum advance bushings often get really sloppy and any vaccum movement show be locked IMHO .

I also have a crank trigger that runs through the stock dizzy cap.
 
Does the dizzy have an electronic type of pickup? Or points. ? I just made one of the Toyota Dizzys use a hall trigger off of the flying vanes.
Basically drilled the side open enough to fit a standard hall trigger. Hopefully timed close . The trigger runs a VW module and coil, back to the rotor, for Vintage rules.
I now use the same tirgger on the flying bolts mounted on the crank .
 
The original distributor uses points. There are conversion that fit Honda and Datsun etc. The 1980s Honda distributors where electronic (magnetic pickup), but still used the same cap, rotor and housing with minor changes. I think that's the way I will go for now. I got one off eBay unused for cheap to mess with. People used to race these things, but all of the practical knowledge has been lost over time. I got a welded cam back from web cams a few months ago. Its not even the biggest they offer in their catalog and the lobes are hitting the valve spring seats so that has to go back for a rework too.
 
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