Last time I bought eight 25's there were two with loose insulators.
Almost as if the body wasn't crimped down.
Obviously those didn't work.

I too have switched to UR4's

 

I have dumped a load of cash into upgrades but I have other projects that I can put the spare parts into.

 

I hate to badmouth any manufacturer, but I purchased a #353901 Grind H-260-2 cam from Crane several years’ back. The truck ran like crap. I put the degree wheel on the cam and checked the duration of the lobes. Some of them were all so far out of whack that it just didn’t make any sense. I called Crane and asked them if the cam maybe slipped while grinding and got out of whack. They called me a shade tree mechanic and that I didn’t know what I was talking about. I put a stock millings cam in and the truck has ran like a bomb ever since.

 

After switching to a different brand of plugs it will smoke all 4 tires now (due to the lockers front and back) there is no lack of power or back firing anymore so I can't blame the cam, now it's just getting the timing tuned in so it starts easier when it's warmed up

 

Gary,
I know I'm not the only one who ran into the cam issue.
Thanks for the backup.

Montecz,
Really glad your truck is performing as expected with a simple swap of plugs!
Doesn't your ignition have cranking retard?

 

Thanks, I did go through several sets of plugs which is why I thought the problem was deeper than just plugs. I just have to back the timing off, it's advanced a little too far right now

 

I'm not sure how you recurve a Pertronix distributor.
Duraspark are pretty simple, and the Crane adjustable advance comes with springs.

 

The pertronix comes with different weights and springs also.

 

So what is your initial, total, and what rpm is it all in?