Two months a go i got my engine completly rebuild and revised but now after i've been wearing it in i wanted to over 5000rpm the rpm's falls to zero and bangs really loud but engine is still running on stationary rpm's, to get him back to work i have to clutch and then he goes on!!!

Can somebody help me 've been looking crazy for a sollution??

The car is 100% standard 3dr 1986 cosworth


Sorry for my english i'm from belgium

 

could be the spark plug gaps are too large, try reducing them them to about 0.6mm

 

is it still on L1 ecu? does the engine management light come on?try turning the boost down!

 

It's still the L1 ecu and no the engine managment light is not going on,
boost pressure has been checked and is not higher in normal 0,7 and max is not higher than 0,9 [img][/img]