Please forgive the lengthy post but I want the situation to be understood, my memory is vague on a few things as it happened a while ago. We run the car on E85 with a new stealth carburetor.
I bought a used 602 it was still running, just smoking a bit through the turns. Took it to a certified engine builder, he is squared away and have no issue with the work he does. Builder put a new MSD distributor in and a serpentine pulley system on the front. I think everything else was a standard rebuild.
I got the engine in the car, it has a MSD box with 3 races on it (I don’t have the designation right now, we sent it to MSD to be tested but it is the box where you set the RPM on the box not with a chip), I ran it with a 358 with no issues coil was old but again I ran it with the 358.
Took it to the track, ran hot laps and part of a heat race and it ran great turned it around 54/5600 for maybe 10 laps and on a restart the engine laid down on me. I finished the heat race but as I was coming off the track the oil light was flickering (I dented the bottom of the pan because I didn’t raise the engine up enough, it was replaced later in the story). Oil light was not on during race.
Got it in the pits and checked the timing and it had jumped either 6 or 9 degrees. Took the car home, checked the wiring which was okay. I put a new coil on it, since it was the only electrical part not new, then we reset the time and I changed the oil. We also replaced the ignition switch in the car since the start button had become a bit finicky. Took it back to the track, no oil light flicker but when I tried to hot lap the engine laid down again, checked the time and it was off again 6 to 9 degrees. Took the car home and I pulled the engine out and took it to the builder, it was at the point the Builder saw that the pan was dented. He replaced the pan and though unneeded the crank, he said it was close on the tolerances and he knows I like to run legal, the block was checked and it was a standard rebuild again.
Engine back in the car and raised up to clear the pan I also added a racing alternator, took it to the track and we were able to hot lap and ran about 5 laps in the feature (no heat race) until I crashed. Car ran great, the only issue was that I have a reverse mount power steering pump and I had the belt too tight, it broke and I had no PS. Fixed the body and came back the next week and the engine laid down again during hot laps, it felt different this time so I just turned the engine off on the track and they pushed me back to the trailer. Since the feel was different this time we didn’t start it back in the pits to check the time.
Pulled the engine and took it to the builder, he said it was a detonation issue and it hurt the rod bearings. I pulled all of the MSD stuff and sent it to MSD to be tested, it all passed. All of the issues seem related to timing, but I’m not sure. The engine builder hasn’t experienced this before and has offered to put it together and take it to the dyno on his dime to test it there, but I’m not comfortable with pinning this on someone if it isn’t their fault. Honestly I’m ready to punt on the engine, I have less than 30 laps and a lot of cash tied up in it.
Have any of you guys experienced this type of thing before?