Locked out distributor advance question - Page 2

rod butcher · 05-13-2019, 08:48 AM

I'd just set the timing at 3000 rpm as you get a few degrees of timing difference from idle to 3000 from distributor, cam/distributor gear clearances and cam end play.

Dave Muller · 05-13-2019, 01:08 PM

It's done, one small lock washer, probably for a #10 screw, fit perfectly. Did not noticeably increase the space between the two surfaces but was just enough to be able to tighten down firmly. No more movement at all.

Bruce Fulper · 05-16-2019, 01:27 AM

Between all of the allowable tolerances of the cam and dist. gear and the rubber band up front, (timing chain) you'll never remove all of the slop. But don't worry about it. When it's floored its tightened up.

Dave Muller · 05-16-2019, 09:40 AM

Quote:

Originally Posted by Bruce Fulper

Between all of the allowable tolerances of the cam and dist. gear and the rubber band up front, (timing chain) you'll never remove all of the slop. But don't worry about it. When it's floored its tightened up.

Agreed, when I said no more movement I meant in the centrifugal advance mechanism itself. There was no noticeable change in the gear clearance, and I didn't add to the shims.

Mark Yacavone · 05-16-2019, 12:13 PM

Back in the 70's, GM sold a pack of distributor shims. They were .010 or .015 maybe ?
Ten to a pack , and it would take about half of them to shim up a distributor gear to remove most of the play there.
Always wondered why they left them that loose . GM must have seen as a hi-po issue, or they wouldn't have sold them.
I wonder if they are still available or somebody has them as NOS ?

Coleydog · 05-16-2019, 12:56 PM

I always use one very light spring on the advance. Engine starts at a small degree then flings out after 500 rpm to full advance. Easy to start any high compression engine. Also use a locking collar to allow no shaft up and down movement. I use a stock dist except when needing a tach drive.
Mike

brian schuetta · 05-18-2019, 08:40 AM

I thought the Summit brand distributors like the ready to run type were MSD. I found a pack of Moroso brand distributor shims at a speed shop a few months ago.

Bruce Fulper · 05-18-2019, 02:03 PM

I've been building distributors for 30 years, and no longer can find shim kits. If anyone knows please share. Thanks.

1320racer · 05-18-2019, 02:15 PM

Quote:

Originally Posted by Coleydog

I always use one very light spring on the advance. Engine starts at a small degree then flings out after 500 rpm to full advance.

This^^^ I would never recommend a locked out distributor when using a stock or stock type distributor. I’ve been running my distributors with 18-20 degrees mechanical advance and all in by 2000 rpm for 25 years. The reward is no hard starting, no kickbacks, no broken flexplate teeth and no broken starter drives. Spins over like the plugs are out.

GTOMayhem · 05-19-2019, 04:38 AM

Quote:

Originally Posted by Bruce Fulper

I've been building distributors for 30 years, and no longer can find shim kits. If anyone knows please share. Thanks.

https://www.competitionproducts.com/.../#.XOEV0aR7mUk

Rick Thomason
GTOMayhem

05-13-2019, 08:48 AM	#11
rod butcher Member Join Date: Dec 2005 Posts: 252 Likes: 304 Liked 132 Times in 27 Posts	Re: Locked out distributor advance question I'd just set the timing at 3000 rpm as you get a few degrees of timing difference from idle to 3000 from distributor, cam/distributor gear clearances and cam end play.

05-13-2019, 01:08 PM	#12
Dave Muller Member Join Date: Apr 2014 Location: Mesa, AZ Posts: 497 Likes: 162 Liked 223 Times in 73 Posts	Re: Locked out distributor advance question It's done, one small lock washer, probably for a #10 screw, fit perfectly. Did not noticeably increase the space between the two surfaces but was just enough to be able to tighten down firmly. No more movement at all.

05-16-2019, 01:27 AM	#13
Bruce Fulper Senior Member Join Date: Aug 2004 Location: So. Cal. Posts: 651 Likes: 4 Liked 54 Times in 33 Posts	Re: Locked out distributor advance question Between all of the allowable tolerances of the cam and dist. gear and the rubber band up front, (timing chain) you'll never remove all of the slop. But don't worry about it. When it's floored its tightened up.

05-16-2019, 12:13 PM	#15
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,819 Likes: 2,910 Liked 5,127 Times in 1,955 Posts	Re: Locked out distributor advance question Back in the 70's, GM sold a pack of distributor shims. They were .010 or .015 maybe ? Ten to a pack , and it would take about half of them to shim up a distributor gear to remove most of the play there. Always wondered why they left them that loose . GM must have seen as a hi-po issue, or they wouldn't have sold them. I wonder if they are still available or somebody has them as NOS ? __________________ "We are lucky we don't get as much Government as we pay for." Will Rogers

05-16-2019, 12:56 PM	#16
Coleydog Senior Member Join Date: Jul 2014 Posts: 572 Likes: 39 Liked 53 Times in 38 Posts	Re: Locked out distributor advance question I always use one very light spring on the advance. Engine starts at a small degree then flings out after 500 rpm to full advance. Easy to start any high compression engine. Also use a locking collar to allow no shaft up and down movement. I use a stock dist except when needing a tach drive. Mike

05-18-2019, 08:40 AM	#17
brian schuetta Member Join Date: Apr 2005 Location: san antonio tx Posts: 259 Likes: 5 Liked 28 Times in 15 Posts	Re: Locked out distributor advance question I thought the Summit brand distributors like the ready to run type were MSD. I found a pack of Moroso brand distributor shims at a speed shop a few months ago.

05-18-2019, 02:03 PM	#18
Bruce Fulper Senior Member Join Date: Aug 2004 Location: So. Cal. Posts: 651 Likes: 4 Liked 54 Times in 33 Posts	Re: Locked out distributor advance question I've been building distributors for 30 years, and no longer can find shim kits. If anyone knows please share. Thanks.