Higher RPM miss
Thread Starter
Racer
Joined: Apr 2001
Posts: 269
Likes: 0
From: Golden Colo.
Higher RPM miss
Was checking the vac and mech advance. Running RPM up and watching timing with adjustable light. Around 2200 rpm started missing flash from timing light. At first intermittant but as rpm rose miss was worse and worse. Switched to different timing light with same results. Switched timing light to different plug wires with miss not as severe or non-existant.
This is on a 80 Delco HEI. Had this same problem a yr. ago but not as bad and was blamed on the timing light. Now even with new coil and module still have the same problem. Would this be a reluctor and/or magnetic pick-up problem? If so can these parts be bought seperate or would you recommend a whole new distributer? Has anyone else had this type of distributer problem missing on higher rpm's?
Thanks for any input
This is on a 80 Delco HEI. Had this same problem a yr. ago but not as bad and was blamed on the timing light. Now even with new coil and module still have the same problem. Would this be a reluctor and/or magnetic pick-up problem? If so can these parts be bought seperate or would you recommend a whole new distributer? Has anyone else had this type of distributer problem missing on higher rpm's?
Thanks for any input
Melting Slicks
Joined: Jul 2004
Posts: 2,867
Likes: 195
From: Maryland
Might check the drive gear end play. Excessive end play
can cause "spark scatter" which results in erratic timing.
Shim the gear clearance to under 10 thousands .
can cause "spark scatter" which results in erratic timing.
Shim the gear clearance to under 10 thousands .
Last edited by Donald #31176; Sep 10, 2007 at 09:25 PM.
Thread Starter
Racer
Joined: Apr 2001
Posts: 269
Likes: 0
From: Golden Colo.
Shiming if needed was my next step. Seems like a lot of scatter if thats the case.
When checking earlier I had switched to different wires. Some not as bad, some no problem. Thats why I thinking prossible pick-up problems.
When checking earlier I had switched to different wires. Some not as bad, some no problem. Thats why I thinking prossible pick-up problems.
Thread Starter
Racer
Joined: Apr 2001
Posts: 269
Likes: 0
From: Golden Colo.
Wires are fairly new, 4 yrs very few miles. Taylor SpiralPro if I remember correctly. Have tried switching different wires-same problem.
Pulled dist. and she could use some shimming. Its just strange the major miss is on #1. Listening to exhaust can't tell if there's a actual miss at that high rpm.
Pulled dist. and she could use some shimming. Its just strange the major miss is on #1. Listening to exhaust can't tell if there's a actual miss at that high rpm.
