Hyperspark distributor fitment issues

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Joined
Jan 15, 2023
Messages
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Location
Greenwood, IN
Just wanted to see if anyone else has run into this and if this is a good enough fix. I'm in the process of building my engine. So just wanted to make sure distributor fit with no issues. When I dropped the new Hyperspark distributor assembly in the block, I noticed the flange does not sit down on the block. Thought to myself, that ain't right... Took the old distributor and plunks right down there no problems. So I got the manual out, the instructions give their min/max measurements for the bottom of the gear to the bottom of the mounting flange with the shaft pushed completely inwards. I can't say why, but I took the cap and rotor off. Made the measurements. The stock distributor for reference measured close to the minimum. The Holley measured close to maximum, with 0.001" to spare. But within spec. So I went back to the block, dropped in the distributor, and flange mated up to the block with no problem. Thought to myself what was different? Made sure no debris in the way, the oil pump and drive shaft are not installed yet, so why did it do that? So then I figured let me put the cap and rotor back on. That is the issue. When I tried to screw the cap on, the distributor housing started lifting out of the block! So I took the cap off and noticed the bottom of the cap had red plastic around the coil contact. The height of the rotor housing is too tall. Called Holley customer service and they gave no help. So I asked if I ground down the plastic on the rotor to make clearance, would this cause any issues. They saw no issues with that, but was curious if anyone else had run into this on their Holley / MSD distributors.
 
I had sent it back once to have a steel gear put on. When I spoke to them on the phone, according to them, they use a "jig" to make sure tolerances are within spec. I already did grind down the rotor, and all seems good at this time.
 
Are you sure the distributor went over the oil pump drive hex.

Even out of time try it in another position.

I have the dual sync in my 351c. So far so good.
 
did you rotate the cam shaft? about half the times i have installed a distributor, i have noticed the gear does not seat and mesh well with cam until the engine rotates a little. rotate it clockwise and it will pull the shaft own. ccw will push it up.
 
Oh yes, I've went thru everything I could think of. It all seemed to come down to the rotor hitting the cap. I've removed some of the plastic and everything seems to be okay right now. Hopefully I'll be getting this engine installed around the end of the month and fired up. I'll report any issues, and Holley says if there is a problem, my warranty still stands.
 
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