Max sump under car.

[robo]

Cant find any reference anywhere as to the most sump/bellhousing that can be below the floorpan when installed before something takes a lump out of it?

Bob

[ayjay]

That may depend on the height of the object you hit :o

I'd say anything below floorpan level is a likely target:(

[7ishNZ]

3" clearance under the sump would be a good figure to aim for. ( If the ideal height under the rail is 5").

Make sure that at full down suspension travel there is still air under the sump!!

[snapper]

There is no point in cutting the sump shorter than the bellhousing.
Then it's about how high the rocker cover is to the bonnet.

[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

[Cyberbeej]

Surely it all depends on the standing still height off the road and the travel on the shocks till it bottoms out.

I mean, lets say you have 125mm floor to chassis gap and a travel on the shocks of 100mm, going on the theory that your suspension should be set at half way in the 100mm travel (50mm) that leaves you 75mm clearance at full suspension compression.

Just adjust the figures and that will show you whats available for your sump/ bellhousing.

Does this make sense????

[AshG]

end of the day i have got 120mm ground clearance and i can touch down a little on really bumpy roads with dips and crests

[vmax1974]

Cant imagine you touch down that much going past mickeys on bluebell hill

[AshG]

nah iam talking about the country lanes :D also managed to ground it out a couple of times racing round olivers mount up norf. p.s i can walk to micks caffe from my house :D unfortunately mick is no longer around after getting his head blown off with a shot gun but i know his son ray he was in my brothers year at school :D

[vmax1974]

I used to go in there every morning when I was working for streamline out of maidstone

[snapper]

Bump stops on the shocks, these can be cut to fit and have a rising rate of compliance. If you then regularly hit the bump stops you need a little more spring poundage.

[baz-r]

what spring rates you on ash? and was that with the pinto or the turbo motor?

[AshG]

i have 350's front and 250's rear. saab lump is roughly the same weight as the pinto lump. its never an issue of suspension travel and i have never hit a bump stop. the fact of the matter is that the car is 120mm off the ground and if it goes up a hill then down into a dip the suspension will load up. if its loaded up and something is high in the road it will touch down. making the springs harder would just make it horrible to drive over that rough kind of ground. at the end of the day i have driven loads of 7's and they all tend to do it unless the owner doesn't know what they are doing and has the thing up on stilts

the inevitable thing with all sevens even my mates r300 caterham is that at some point or other they will touch down. so its best to scrape a bit off the bell housing rather than the sump. btw there are 3 people in my club that need their sumps welding up for this exact reason.

[baz-r]

i only ask as i have a cut'n'shut alloy sump on me zetec :o and i set the bottom same as the bell housing :eek:

as im running full length shocks with diffrent length springs it looks like its going to be a suck it and see.

i was thinking of puting some bump stops in them to be on the safe side

[robo]

I can feel a skid plate coming on like the one 7ishnz suggested!

[7ishNZ]

I have about 50mm of sump and bellhousing below the chassis rail. I can take about 20mm from the bottom of the bellhousing. I will be making a skid plate.


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