Terry Oxandale
Skinny Man
I've see inverted 930 boxes being used from time to time, but after tonight's mock-up, my fears were confirmed. I've got a question about half-shaft geometry with an inverted box.
Using a 26" tire, the axle centerline (perfectly horizontal) is obviously about 13" above the ground. This puts the crank centerline approximately 10" above the ground, which means that unless I use a dry-sump system with the LS block, my pan is going to be in the weeds.
In order to get the pan up to a 5" ground clearance (that is the clearance of the tube frame at the rear), I've got to raise the entire assembly up by about 3", which puts the half-shafts at about a 10º angle. The 930 CV is capable of 28º (I believe) under torque, but the 10º appearance seems to be a lot more than any view I've ever seen of this configuration.
Options?
1) Tilt the engine a few degrees just as has been done for decades on RWD cars, but then I'm concerned about oil pooling at the back of the 930 case.
2) Lower the engine an inch or so to help improve the geometry, but risk damage to an aluminum oil pan,
3) Dry sump (probably my last option)
4) Combination of 1 & 2
5) Find some really huge tires for the rear so I can lower the car, and re-align the half-shafts.
So what kind of oil pan clearance is had on the 930 inverted boxes out there, and what size tires and chassis ground clearance is being run?
Using a 26" tire, the axle centerline (perfectly horizontal) is obviously about 13" above the ground. This puts the crank centerline approximately 10" above the ground, which means that unless I use a dry-sump system with the LS block, my pan is going to be in the weeds.
In order to get the pan up to a 5" ground clearance (that is the clearance of the tube frame at the rear), I've got to raise the entire assembly up by about 3", which puts the half-shafts at about a 10º angle. The 930 CV is capable of 28º (I believe) under torque, but the 10º appearance seems to be a lot more than any view I've ever seen of this configuration.
Options?
1) Tilt the engine a few degrees just as has been done for decades on RWD cars, but then I'm concerned about oil pooling at the back of the 930 case.
2) Lower the engine an inch or so to help improve the geometry, but risk damage to an aluminum oil pan,
3) Dry sump (probably my last option)
4) Combination of 1 & 2
5) Find some really huge tires for the rear so I can lower the car, and re-align the half-shafts.
So what kind of oil pan clearance is had on the 930 inverted boxes out there, and what size tires and chassis ground clearance is being run?