parkwood60
Well-known member
Our 1979 Ford Fairmont 24 hours of Lemons road race car
So we blew up our first rebuilt motor (Direct mount 2bbl, .060" milled head, 264 cam, new bearings, sealed power hyper-eretic pistons) when we over revved it. We we leading our class at the end of Saturday's racing, then Sunday morning our driver left the C4 in 2nd when the green flag dropped. The factory tach was reading something like 7500rpm when it went boom, the piston disintegrated and took a good portion of the cylinder wall with it.
We swapped in a "rebuilt" motor from a 1979 Fairmont, bolted up an SROD (later a T5) and drove in 3 full race weekends, then put the cam thru the side of the block in practice for the next one.
The next motor we spared no expense with all the good parts from Classic inlines (ARP bolts and studs, Silvolite Tempo HSCC pistons, 274 hydraulic cam), plus the direct mount 2bbl head we had been using on all the other blown up motors, after checking it out and cleaning it up. This one ran great in the spring Sears Point race and we finished 44th out of 175 cars, and 2nd in class. The next race it blew up in 3 hours.
It really looks like the Tempo piston just came apart at the oil ring. The 2nd blown motor may have come apart just due to the number of race miles we had on it without checking the tightness of the rod bolts.
I already asked a similar question to the Lemons boards, but they did not come to any consensus. http://forums.24hoursoflemons.com/viewt ... p?id=27214
So you guys have more collective knowledge than anyone when it come to these motors. Were these just 3 different unrelated issues? Or is there some basic issue were aren't dealing with in our prep?
So we blew up our first rebuilt motor (Direct mount 2bbl, .060" milled head, 264 cam, new bearings, sealed power hyper-eretic pistons) when we over revved it. We we leading our class at the end of Saturday's racing, then Sunday morning our driver left the C4 in 2nd when the green flag dropped. The factory tach was reading something like 7500rpm when it went boom, the piston disintegrated and took a good portion of the cylinder wall with it.
We swapped in a "rebuilt" motor from a 1979 Fairmont, bolted up an SROD (later a T5) and drove in 3 full race weekends, then put the cam thru the side of the block in practice for the next one.
The next motor we spared no expense with all the good parts from Classic inlines (ARP bolts and studs, Silvolite Tempo HSCC pistons, 274 hydraulic cam), plus the direct mount 2bbl head we had been using on all the other blown up motors, after checking it out and cleaning it up. This one ran great in the spring Sears Point race and we finished 44th out of 175 cars, and 2nd in class. The next race it blew up in 3 hours.
It really looks like the Tempo piston just came apart at the oil ring. The 2nd blown motor may have come apart just due to the number of race miles we had on it without checking the tightness of the rod bolts.
I already asked a similar question to the Lemons boards, but they did not come to any consensus. http://forums.24hoursoflemons.com/viewt ... p?id=27214
So you guys have more collective knowledge than anyone when it come to these motors. Were these just 3 different unrelated issues? Or is there some basic issue were aren't dealing with in our prep?