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misfiring under load

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I think I remember dwell is the amount of time the points are closed so yes closing the points increases dwell
 
Twas the dwell.
I had to go to eBay to find a dwell meter, and it arrived today. Dwell was about 30, and I increased it to 37, and the missing went away.
What is the "spec" for dwell?
 
My TR3 workshop manual says 60 deg.
 
OK, still learning here. Dwell meter says 4 cylinder reading is twice the 8 cylinder reading. So I was at 60, and increased it to 74.
Or... my eBay meter could be off a bit.
I think I will enjoy the smoothness until I can get back into it and look a little more closely.
 
If you go with something like Pertronix you can forget about dwell.
 
Right. And only worry about things like gap to the pickup, magnets falling out, electronic module failing, etc.

Personally I've never worried about dwell ... just set the point gap somewhere in the vicinity (matchbook cover) and go /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
That's a pretty scary scenerio you've painted there, Randall. I'll admit to keeping my old points and condensor stashed in the boot but with nearly 2 years of having the Pertronix, I feel it's been reliable enough. As they say though, YMMV.
 
fogdot said:
Twas the dwell.
I had to go to eBay to find a dwell meter, and it arrived today. Dwell was about 30, and I increased it to 37, and the missing went away.
What is the "spec" for dwell?
Click to expand...
That is not a huge shift in dwell which is creating a problem I suggest that you also double check all the connections on the low voltage side for good clean contact / no corrosion / tightened up bolts etc. a bad connection will make it all much more sensitive to the dwell being to short.
 
My Pertronix has been operating since 2001. I have not had one problem with it. I have not made a single adjustment to it. I am quite pleased with it and frankly have not heard one single bad comment about it.
The nice thing about an electronic ignition upgrade is that it eliminates parts that constantly need adjustment and wear out. Our distributors are around 35 years old and have play in them due to wear. Trying to maintain a set gap (dwell) on a wobbly shaft is not easy. IMHO I think it is should do upgrade.

Now that I have said this I feer I have invited Mr. Murphy to go for a ride with me.

Interesting comments on dash pot oil weight. Will have to experiment with this this summer.
Rick
 
The only bad thing about Pertonix is that the un-familiar or careless can wire them incorrectly or leave them powered on with the engine not running. They will overheat if you leave the ignition on (engine off) and they will not survive reverse polarity.

As for inviting Murphy... everyone I know who has Pertronix carries a clean set of points and condenser in the boot. It's a very quick job to put the points back in should you have to.
 
I installed my pertronix over 2 years ago, if you can follow instructions its hard to wire it backwards, no problem at all. the cap and rotors are more of a problem than the pertronix
 
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