1982 Dodge 1 ton 4x4

I had $10,000.00 put into this engine and it is now a high performence engine, putting out 490 hp to the ground with about 550 plus fp torc.
The engine ran great at the shop and on the dyno but once I got it home it started shutting down once it had been driven for a short time, and some times after about 45 min to an hr it would start up, go for a while and shut down, every time we check it out, it seems to not be fireing, no spark! now it won't start at all, I've had a few people work on it and no one seems to know what's wrong with it, I even took it to the Dodge dealer, and they couldn't get it running eather, ( strange, I thought ) but they still charged me over three hundred dollors to have it there for almost a week, and only changed a few wires, it got me home, but started up again, any one out there able to help me? I'm at my wits end. I don't know what else to do. thank you. :banghead:

hey if you have a 3 prong oil pressure switch with a poor conn. it will shut down ign.