boxter engine
 

boxter engine: after replaceing 2 inlet valves& 4 exhaust valves on o/s bank,
ran the engine for few hours, running ok. next minute engine cuts off, checked
compression- no compression both banks this time, removed engine again and complet strip to find out - all exhaust valves bent. any suggestions as to the cause

Sounds like the timming might be drifting off a bit after awhile. maybe a week tensioner. No sign of the valves hitting the pistons?
I'm just guessing.
I assume it still has a factory cam's in it and no custom high lift cam. Though if the lift was to high it would not have ran very long at all.

Excedding redline can cause valves to bend on some engines. But with the revlimiter I don't see that happening.

What where you doing when the valves bent in the first place, how many miles on it, and was the engine modded in anyway?

Richard