924Board.org

[Dutch924-racer]

I saw mittelomotor modified the 931 sump, what is the benifit of this ?



Other modifications I spotted in the video:

ARP style headbolts
Cometic head gasket
Special pistons
Solid lifters
Performance cam
Adjustable cam gear
Other KKK turbo, K26/8 ?


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937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller

[peterld]

The tray they have fabricated and placed in the sump is designed to keep the oil where it should be........in the bottom of the sump, so that the oil pickup is always immersed.
Without it, under hard cornering/braking, and particularly with sticky tyres, the centrifugal forces will force the oil up the walls of the sump and block, away from the oil pickup, which then cavitates (sucks air) = no oil to bearings, etc = disaster!
The tray also stops the crank from trying to force it's way through the oil; which at high revs, at best will cause severe shudder, but usually just breaks the crank/rods.
Many engine builders will run a windage tray bolted directly to the bottom of the block via the main caps (usually), as well as baffles in the sump. Options include little doorways in the baffles to regulate the flow of oil.
The ultimate solution of course is to dry sump the motor but that = big $$$$
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80/81 932/8 ROW

[Dutch924-racer]

good explanation Peter, many thanks!
_________________
937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller