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Trevor Jones · 08-19-03, 07:06 PM

Lee,

A bit of crude geometry might help reduce your concerns. You mentioned that you want to get the bottom of the block 6.5" from the bottom of the chassis. I assume the centreline of the crank is on the plane of the base of the block.
If I also assume that you plan to run about 5" ground clearance, that means your crank C.L. is about 11.5 inches above ground level. Assuming you are running about 26" dia tyres, this means that the centreline of your rear hubs will be about 13" above ground level (any neg camber will reduce that)

Your half shafts should be about 12" long and angling them down 7 degs should be no problem at all (look at the angle on some formula cars). This means that the inboard hubs can be about 11.5" above ground level.

The output shafts on a Renualt 30 g'box are about 1.5" below input CL or (11.5 -1.5) = 10 inches above ground level.
By canting the engine and g'box up at the back about 2.5 degs, the g'box o/p will be aligned with the halfshaft.
2.5 degs is very slight and if you could lower your sump depth to about 5" you could mount your engine and g'box completely flat.

My installation is dead flat using a R30 g'box.

Hope this helps a bit.

08-19-03, 07:06 PM	#2 (permalink)
Trevor Jones Rookie Join Date: Oct 2002 GT40: Ontario Canada Posts: 54 Rep Power: 6	Re: Low Engine C of G / Inverted Gearboxes Lee, A bit of crude geometry might help reduce your concerns. You mentioned that you want to get the bottom of the block 6.5" from the bottom of the chassis. I assume the centreline of the crank is on the plane of the base of the block. If I also assume that you plan to run about 5" ground clearance, that means your crank C.L. is about 11.5 inches above ground level. Assuming you are running about 26" dia tyres, this means that the centreline of your rear hubs will be about 13" above ground level (any neg camber will reduce that) Your half shafts should be about 12" long and angling them down 7 degs should be no problem at all (look at the angle on some formula cars). This means that the inboard hubs can be about 11.5" above ground level. The output shafts on a Renualt 30 g'box are about 1.5" below input CL or (11.5 -1.5) = 10 inches above ground level. By canting the engine and g'box up at the back about 2.5 degs, the g'box o/p will be aligned with the halfshaft. 2.5 degs is very slight and if you could lower your sump depth to about 5" you could mount your engine and g'box completely flat. My installation is dead flat using a R30 g'box. Hope this helps a bit.