[mback12000]

Originally Posted by Formulajones

Actually you don't even have to worry about rubbing block wear. The box doesn't care what the dwell is. As long as the points open and close that's all it cares about.

If the dwell (point gap) changes, then the timing will change. This takes away one of the advantages of going to a breakerless design. Resulting timing creep will cost fuel economy and performance which may not be so obvious. This is similar to what Lust4Speed pointed out in his post - the inconsistent timing trigger (seen on the distributor machine) of bad points or the Pertronix is hurting you even though you may not realize it. I think most people who claim Pertronix has served them well are judging it by the fact the engine "apparently" runs well.

Yes, you're right, the ECU or MSD doesn't care what the dwell is, assuming they are "edge-triggered" devices. But the timing drift issue remains. My plan is still to ditch the points even though they work perfectly because mine are high spring pressure (to get rpm) and try the FAST points trigger replacement when I get around to it.

[242177P]

Originally Posted by mback12000

If the dwell (point gap) changes, then the timing will change.

As long as you've lubed the rubbing block, wear is negligible. Most
dwell change was the result of live contacts. If they're just triggering
an MSD, they pretty much last forever.

Besides, even crank triggers need attention sometimes.

[Formulajones]

Originally Posted by 242177P

As long as you've lubed the rubbing block, wear is negligible. Most
dwell change was the result of live contacts. If they're just triggering
an MSD, they pretty much last forever.

Besides, even crank triggers need attention sometimes.

Correct. I use the felt pad soaked in oil that keeps the rubbing block lubed pretty well. I don't even bother lubing it as a maintenance practice. Matter of fact the 20 year old points I pulled out of my firebird that had about 45,000 miles on them looked virtually unscathed on the rubbing block and compared identical to the new set I put in. I could have simply filed the contacts on those points to clean them up a bit and put them back in service. There was really no need to even change them but I let a few guys here talk me into it when I was racing the car stating it would help, but the car never ran any quicker.

[mback12000]

Originally Posted by Formulajones

Correct. I use the felt pad soaked in oil that keeps the rubbing block lubed pretty well. I don't even bother lubing it as a maintenance practice. Matter of fact the 20 year old points I pulled out of my firebird that had about 45,000 miles on them looked virtually unscathed on the rubbing block and compared identical to the new set I put in. I could have simply filed the contacts on those points to clean them up a bit and put them back in service. There was really no need to even change them but I let a few guys here talk me into it when I was racing the car stating it would help, but the car never ran any quicker.

Sorry, I don't mean to beat this to death, but if you didn't put a dwell meter on it you can't really know what changed in 45k miles. I'm not convinced you can see normal rubbing block wear. In 45k miles the nylon just isn't as long as it used to be and the dwell is different and therefore your timing has moved. Unless of course you have done maintenance. Yes I know what you're probably thinking, the car ran fine, lol.

[Formulajones]

Originally Posted by mback12000

Sorry, I don't mean to beat this to death, but if you didn't put a dwell meter on it you can't really know what changed in 45k miles. I'm not convinced you can see normal rubbing block wear. In 45k miles the nylon just isn't as long as it used to be and the dwell is different and therefore your timing has moved. Unless of course you have done maintenance. Yes I know what you're probably thinking, the car ran fine, lol.

I put a dwell meter on it once a year, never had to touch the adjustment for many years.

Usually what I find (have 4 cars with points) is that an initial new set of points requires a few periodic checks, and usually a quick adjustment, but after a few thousand miles they tend to settle in and I simply don't have to adjust anything. I still make it a routine to check it once a year but I never find they need anything despite the internet rumors.

Here's the car with a 20 year old set of points in it. As I usually do once a year, or when planning a track outing, I toss on the dwell meter and check it. It's always a rock solid 30 degrees. Simply didn't have to touch it. Like I said, later on that same year, last year, I was talked into replacing the points. The plastic rubbing block was virtually identical to the new set going in. It showed no excessive wear anyplace. These things, if installed properly, using a "good" set of points, oiled correctly, and in a good points distributor that isn't worn or wobbling, are dead nuts reliable and require very little maintenance.

https://youtu.be/er1z7PpqsnY