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When I locked up my engine at Texas World Speedway back in Feb this year, the damage on the engine was too extensive to tell what the cause was. Was it an oiling issue? Was my car tuned too much on the ragged edge? I always tuned my car with heavy engine loads, so I didn't think the tuning was the issue. I had my Defi gauges in the car but I saw nothing unusual uptil the point it locked up. My Motec datalogged the A/Fs and boost and showed everything was running normally uptil that point, so it wasn't overboosting, injector locking up, etc. So this time around with a new expensive built engine, I decided I will need to datalog everything. Got rid of my Defi gauges and all the stock "legacy" wiring, gauges, etc. I then consolidated all oil press, oil temp, fuel press, g-force sensors, even fuel level sensors, to my Motec EMS which datalogged everything. Put in the AIM cluster which talked to the Motec so everything read off one set of sensors. Unfortunately it looks like our engines have real issues with uncovering the oil sump under hard cornering. These are the reports from my last 3 events. Note the pressure axis is in kPa (100kPa ~ 15 PSI). Red/Blue points represents lateral G force of 1G (+/- is simply for left/right) and green points represents no lateral G. Oil pressure at Motorsport Ranch: 
Oil pressure at Hallett: 
I don't know why the Hallett chart is so different from MSR, but Hallett is a tighter track with more elevation changes, and I was also running a higher hp tune, which could account for the differences. The big problem is that there are data points on this chart showing just 30psi of oil pressure at 7000rpm! Why is the oil pressure so low even when there isn't a lot of lateral G's? The reason is the sump gets uncovered earlier in the rpms, and the pump cavitates and never fully recovers by redline. This chart, also from Hallett, shows points connected together: 
This is the last report from Texas Motorspeedway, at this event I have a 3 quart (the big unit) accusump installed: 
The conditions on this track seem to better match the MSR chart, and comparing the two the accusump does offer some improvement, but oil pressure is definitely still not ideal. Unfortunately I think anyone serious about road racing will need to look into investing in a dry sump, otherwise prepared to frequently replace bearings on a preventive basis. BTW, anyone serious about road racing should really invest in some sort of datalogging as well, gauges are not enough. BTW, this is not a problem unique to the Z32, it is well known on the older Z06s (not the current C6 Z06 which has a dry sump from the factory) and Vipers, using race tires would kill stock engines due to oil pressure loss at high cornering Gs. Unfortunately it looks like I found what killed my old engine at TWS; I was finally fast enough around that track that I was entering most corners at ~4500rpm and sustaining a very high average rpm all around the track. High Gs, high hp, and high rpms is a deadly combination.
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Oil pressure report - bad news for road racers - 
