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Oil surge?

Posted: Sat Jul 16, 2005 8:05 am
by Atomrally
Just a question to the guys doing circuit sprints with their FTO's, do you get oil surge on long corners, or have you especially baffled your sumps?

I'm preparing a rallycar with a 6A12 Mivec and would rather know before the car is all assembled, and I ruin bearings and crank.

Thanks.

Posted: Sun Jul 24, 2005 5:21 pm
by RichardH
The RalliArt garage that services my car reckons the 6A12 sump and oil pick-up are quite well designed so as to avoid such problems. The engineer there knows exactly what I use my car for (motorkhana several times a month), and how hard I drive it, and we've discussed the fitting of baffles in the sump... and in his opinion it's not a requirement.

But... I have no oil pressure gauge fitted (yet), so I can't offer any documented evidence that would give you 100% peace of mind. If you're spending the time and effort for a full rally preparation, the sump baffle job is a doddle. My gut feeling is... do it.

- Rich

Posted: Sun Jul 24, 2005 5:29 pm
by Atomrally
Thanks Rich.

Posted: Mon Jul 25, 2005 1:29 pm
by Chiangstar
hey guys...

whats oil surge? and how do baffles in the sump help it?

thanks

simon

Posted: Mon Jul 25, 2005 1:40 pm
by Bennoz
Hey Simon,
Oil surge occurs during hard cornering - all the oil in the sump tends to head to the sides of the sump & problems can occur when all the oil is all at one side, the oil pickup (draws the oil from the sump & distributes it around the motor) cannot pickup any oil (cause its all at the side of the sump due to the cornering momentum.)This can cause the motor to be 'starved' of oil. The oil pressure drops and your internal lubrication levels drop - then when the motor finally picks up some oil into the pickup, the motor wil surge & all of a sudden rev freely & pickup pace if your foot is down. Baffles help to stop all the oil slopping around during corners & keep a level of oil around the pickup at all times. Not so much an issue with FTOs, but it can be with other cars (Some of the baffled sumps that V8s use are a work of art... then going up from there you can have dry sumps as well (whole nother ball game.)

Hope that helps! :wink:
Ben.

Posted: Mon Jul 25, 2005 2:09 pm
by Chiangstar
excellent...

thanks ben