underpressure02

A friend of mine had an lighten crank pulley. I forget who makes it not that it really matters. Anyway he decided he would take it to work and cut off the two ridges for the belts that he does not have. So now the pulley basically is only one ridge (can't think of the word right now) to drive the alternator. I will try and get some pics. So he puts this on and drive about 50 miles and goes to a strip and gets about 4 runs in.

He goes to take his car out for a drive last wed starts it up drives down to get gas and on the way back looses oil pressure. He shuts his car off and coasts into his driveway. Takes the oil pump out yesterday and the gear is broken in about 4 or 5 pieces. I will try and take some pics of this also.

So do people think that this lightened crank pulley destroyed this oil pump/gear or was it just on its way out? I think it had to do with the pulley he thinks it was just time for it to let go.

NRN GT4

yeah, I would have to say the lightened pulley killed the pump, becuase the harmonics had nothing to be absorbed by so the pump to the shock instead of the pulley as it is intended. Sorry about your freinds luck

randbcustoms

nrn nailed it on the head... vibration and frequency shattered the oil pump.. actuall common with high rpm race engine... the dampner needs to be their.. it's name says it all harmonic dampner..as weird as it is. the stock oil pump seems to be best at fighting it to. billet pumps break ALOT. i only use factory ones now..but i alway use a dampner.. never broke one...seen alot broke though..