Hi my rs series 1 car broke down last week after only 500 miles after re build of 2.1 zvh engine. It would turn over and try to start but just cuts out. Took it into re performance in bury and he said that compression was down and one cylinder was as low as 30%. Whats likely to be the cause? any ideas. He took the head off and all looks fine and now he says he wants to take all the pistons out to check them. This car never smoked as it is all brand new inc pistons rings etc. Any ideas or help would be grateful or this could just go on and on .

 

has the head been machined at all? iirc you need to weld a bit of extra ally to one side of the head & then skim it so it will clamp down on the head gasket properly in that particular area

 

Could be a number of things but years ago i had the same problem and it turned out to be two pistons broke between the rings.

 

either way not what u whant 2 happen