... Boiling of coolant in the right side cylinder head will cause one pair of exhaust seats to droop...leading to exhaust valve being burnt....leading to major damage. We are making the necessary changes to the cooling system [140gpm water pump and larger expansion tank] as well as a major redesign to the heads to promote coolant travel into the exhaust seat area. More intercooling, larger injectors, better fuel, all should make for an exciting season. Lynn is back cracking the whip and the project is picking up steam again.
Hope to see you at the May meet.
I'm not sure if it's exhaust seat dying that causes piston overheating or piston overheating that causes the exhaust valve to croak. While I've torn down engines that injured pistons with 100% good seats and valves, I haven't seen the opposite yet. When the aluminum comes off the pistons, it forms a crystalline coating on the valve stems, naturally on the exhaust. That can cause the valve to stay open a hair and burns it.
Yup, after we drag race Casper on March 7 in Arizona, then we switch the truck back over to LSR mode for El Mirage in May and will try to figure out why it fell asleep at 155mph at El Mirage. The ABS system, the TCM, and ECM system are all suspects in the crime. While the computers said everything was hunky dory, it would peak to ~160mph at roughly half track, then fade back to 155mph which is a magic number to the computer. 155 is 255 in metric (kilometers per hour) and the computers are written in metric. It's kinda cool to watch the speedo at 155mph, it drops back to zero and starts counting all over again. Wish I could dump the factory computers but that's not happening. At Bonneville it went 181mph before I had to let out of it (175 speed limit), and on the dyno it ran at 198mph under load. But at El Mirage with the exact same setup, no dice.
Our goal is to run 200.000000 mph
at Speed Week with Casper, finish out the 2009 season, then retire the truck. It's too heavy for dragracing, too light for sledpulling, and too large for LSR. It's claim to fame is that it can do all three, and will never be the best at any of them. Then we will change platforms. Casper is still under warranty, and we are still making payments on it, which might be unique as well. The scene when we trade it in at the dealer might make for good comedy, and I'll try to get in on video. "Yeah, that cage is a factory option..."
But then again, I said I would "retire" it if it ever ran an 11 second quarter mile too. So who knows?
