About three years ago when we first put this motor the hatch i was racing at siiver dollar and the car cut off at 104 mph going through the quarter . I didnt miss shift or hear a noise it just shut down. I roled off the track then tried to crank it with no luck . As soon as we got it to the shop i pulled the timing covers and the timing belt was broke ( brand new honda belt). Checked and had no compression so we pulled the head off and all the valves looked like spaghetti lol. Well none of the valves were broke they were all just bent and yes some hit the piston but the main ones that were bent were where they caght each other . In other words the intake and exhaust valves were open at the same time and locked each other together. I have missed a gear before and bounced off of the 8,500 rev limit no problems . I had never miss shifted but i didnt in this case either. I could have assumed i floated a valve but i think i just got a bad timing belt since i been running the same cams and springs for the last three years . My point is i think in alot of cases when people think a floated valve destroyed there engine that it was more likely something else.
We fixed the head put it back on turned the motor and heard a clunk . When the valves hit the pistons and stopped the motor from turning but the tires were still rolling at 104 mph it put so much force on the crank that it broke it in the center of the number four main journal. It didnt hurt the bearing or the block just broke the crank right in the center of that journal lol. Alot of people say the h23 crank is weak well that is a tone of force so im not suprised it broke and i wonder how many peoples motor came apart for other reasons that was blamed on a weak h23 crank lol. I know that the crank didnt cause my problem but if i didnt know beter i would be like well everybody says the h23 crank is weak must have been the crank lol. We changed the bearings of course even though they looked fine and installed another crank. It has been running fine every since just a bad oem timing belt . i will say that is alot of stress on the rods but were running crower rods and they are still perfect