Accusump - some data

[Silber]

Another question that occurs to me, is if you run the accusump all the time, without a pressure switch, how do you prevent the crankcase from overflowing into the AOS and intake at idle?

[AZ986S]

Hey Silber,

It's been a while since I've posted here, but rest assured all is well!

To answer your question, there is a one-way valve (check valve) that allows the engine oil coming from the oil pump to enter the accusump, but ONLY when this engine oil pressure is greater than the oil pressure on the oil side in the accusump. So when you run with the accusump with the standard pressure switch mode (with electronic valve), the oil will release from the accusump into the engine oil path when the engine oil pressure is lower than the accusump oil pressure. This is only usually momentary (up to a few seconds), but then the engine oil pressure will recover and become greater than the accusump oil pressure as the engine RPMs increase, in effect "recharging" the accusump for the next corner. This is what SAVES your engine from oil starvation... So, in this case, the worst case scenario is coming off the track after a session, hot engine oil, low oil pressure at idle (lower than 35 psi) and so that would dump maybe 1 quart at most into the engine and into the sump. Hence why you need to set you normal oil level lower than max. I also just switch the Accusump Electronic valve to OFF coming off the track after a session so that the accusump is fully recharged, and I only turn it ON when I am on my way onto the track, not at idle.

OK, so what I found with data over a couple years now is this is still not a perfect setup to prevent oil starvation (but better than no protection). There is a time lag when using the pressure switch and electronic solenoid valve, and that lag even if it is 500 milliseconds, can still add up to some engine damage over time. So what I did in my car was add a switch to "bypass" the pressure switch and effectively turn ON and keep ON the solenoid valve when on the track. What this does is it simulates a mechanical valve and virtually eliminates any time lag. I've had this setup for 3 years now and 40+ events driven hard on the same engine, using Mobil1 15W50. Stock AOS with X-51 baffle system. No oil consumption. The engine gets run hard, but I rarely redline it, preferring to shift around 6,500-6,800 RPM.

So I would say it has had a positive impact on reducing oil starvation and extending the life on this 3.2 engine, considering that I had the previous engine for only 14 events prior to it failing.