Max sump under car.

[robo]

Have tried to get the answer to this a couple of times, I am about to take engine and box to talon for chassis mock up and need to know what can stick out under the car before it becomes a problem. The answer will determine overall chassis height as that can changed . Is 2" sorry 50mm to the young ones to much?

Bob

[7ishNZ]

2" would be OK.

[robo]

7ishnz have you ever seen our roads? The unmade ones in the aussie outback are smoother.Potholes that people abseil down and speedbumps through towns that people with vertigo have to avoid. Are you sure 2" is ok?

Bob

[AshG]

my sump is about an inch below the bottom chassis rail. the gb is about 1 1/4 inch lower than the bottom chassis rail. i have managed to touch the gearbox down a couple of times when pressing on over bumpy roads.

personally i would say any more than an inch under the chassis rail is going to end in tears at the side of the road

[MarkB]

Better if you can have it level with chassis rails, as Ash mentions DON'T go lower than an Inch or you risk taking a chunk out of it on our crap roads!!!

[7ishNZ]

The best solution is sump level with the chassis. This is not usually possible even with a dry sump, as the bellhousing will now be the lowest point.
The best result is a compromise between bonnet height and bellhousing. 3" clearance under the sump/ bellhousing is the usual for 7's here... some have more, some less.
If you are worried, make a skidplate that will protect both the sump and the bellhousing.
Alternatively... fit airshocks

[AshG]

i made sure my bellhousing was a little bit lower than the sump and it turned out to be a good idea as if i clout the bellhousing it tends to stop the car going any lower and catching the sump