Z32 crankshaft is cross-drilled on both the mains and the rod journal. The oil hole on the journal goes all the way through to the other side so you can see through it. This provides oil for 360 degrees of crank rotation because the top main bearing half is grooved. One hole feeds for 180 degrees of crank rotation. As one hole turns to the bottom half of the main bearing it becomes blocked. The other hole on the opposite side gets unblocked and feeds from the top half of the main bearing . It feeds the mains and the rods. As an added bonus the rod journal is cross-drilled as well. This helps high rpm oiling granted everything else is up to par like the high volume oil pump.

 

It is hard to tell in this picture but the oil holes go all the way through . The oil feed from the main is in the center of the crank

Has this been proven to work - I mean it doesn't weaken it does it ?

Err, excuse me but there haven't been many posts on here relating to bearing/crank failure, admittedly i would have thought this was a good idea on a race lump, but really it's a tad OTT for a road car, even with the power some people are pushing.

 

Tim

On the JUN 300ZX which porduced over 1000bhp and had a top speed of over 260mph, they used the original crank. So I think its strong ;)

 

Stuart

This is common practise with alot of race teams, cranks are really not the problem on this car at all. the lemans class winning 300zx als used stock crank as they put it.