Seems like our cars, more specfically our 6a12 Mivec's are prone to a Spun bearing on the crankshaft. I have experienced this on the track and having looked at the for sale section with a guy having two engines with spun bearings it makes me wonder...
I've been talking to the poms about this, they've spun a heap of them. They seem to think its an oil starvation issue & they are currently trying some new high pressure oil pumps. Its specific to the Mivec when its in Mivec range as the extra oil is pumped into the heads, the bottom end starves.
Alternatively, one of the garages over there have worked out a method to changing the crank shell without removing the motor. Personally i reckon its dodgy just swapping out the shells without servicing the crank, but they seem to be getting away with it...
We might need to look into where we might be able to source these pumps from locally at a good price.
I've got a oil pressure gauge on mine, it doesn't seem to loose pressure at high RPM but I do notice on mine that when the engine is a idle the oil level is only on the tip of the dip stick, so I have a feeling that the sump is not big enough for track work but I run a 10w 40 oil, a thinner oil will run back to the sump quicker, so I think that the sump is sucked dry then losing pressure because they hold only 4 litres.
Overfilling would cause the crank case pressure to rise to a point where you'd start blowing seals.
We'd really need to get hold of a Mivec block & have a look at the intricacies of the oil system - things like the location of the sump pickup point can have crucial effects on oil distribution, especially at high rpm while cornering....
I remember seeing on a video somewhere a discussion about oil starvation in RB or SR motors, can't remember which. They fixed it by putting new 'jets'? or flow restrictors I guess in the top of the block to restrict the flow to the head.
Would this possibly cause too many issues for our cars on mivec though, hate to think what might happen if the head can't get enough oil.
