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Discussion Starter #1
I'm trying to get about 35 degrees total advance with an initial advance of 12 to 15 degrees. But my stock distributor has 13L and 15L positions in the reluctor arm (which I switched to 13L for a little more initial advance). Setting it at 12 degrees initial advance - which the engine seems to like a lot - puts the total advance at about 39 degrees (it should be 38 with the 13L reluctor slot). And I get a ping. For now I'm dropping the initial advance back until I get no ping at max advance. The Crane distributor tuning kit wont help since it doesn't have any way to reduce the total advance.

So what do you do to get less total advance? I don't see reluctor arms listed in any catalogs - is there a place to buy 'em? Am I going to have to go with an aftermarket distributor? I was thinking I could slip a very short piece of hose over the reluctor arm stop making the range of movement smaller and decreasing the total advance.

Thanks!
 

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I beleive you can by the reluctor arms at Summit (don't have a catalog here at work though, to confirm). What's you're compression ratio? 38 deg. should be ok with less than 10:1 compression.

I have my timing set up very similar to yours. I'm running an initial 15 with the 13L reluctor for a total of about 41 with no pinging. This is on a stock 289 block/heads with Performer RPM cam/intake.

I would think your idea a piece of hose over the reluctor arm stop would work well for limiting the total advance. You'd just have to use a timing light to see where you're at and whether you need a thicker/thinner hose.

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Thanks for the reply! I'm running closed chamber 4v cleveland heads on a 2v bottom end, so according to one book it should be at about 9.6:1 compression. Maybe the cleveland heads like to ping more?

This distributor tuning business is cool! I never knew how much could be done with stock hardware.

I think I'll give the hose thing a try. This engine runs so much better with more initial advance.
 

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I'd be interested to hear how your trick turns out. I have a very similar setup (same heads etc). I gave up with the stock distributors as like you say, you need about 12 deg initial for the engine to behave well at idle and then the total somewhat less than 38 to not get a ping with premium gas. I ended up changing to an MSD distributor (they are great) with 12 deg initial, 31 deg total advance and running cooler NGK plugs, UR6's to get rid of the ping. The plugs made a big difference and I am now planning on giving it some more total advance to see what else I can get out of it.


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According to Bob Mannel's book, there was a small rubber tube that goes over the reluctor arm stop for the early model distributors. You're idea is a good one.

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I'm going to try the rubber sleeve trick and see if that doesn't give me the total advance. I'll post the results.

Thanks much!
 

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I have found from experience that the reluctor arms are not accurate. Eg. 13L X 2 + 15 intial should =41 degrees. I have curved three similar distributors in the past year and only one of the three were accurate. The other two were close to 50 degrees after checking with a timing light. I added epoxy to the arm stop to drop the advance to 36-38. Next time I'll try rubber vacuum hose on the stop.

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