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Clearance
interestedparty - 18/5/02 at 08:08 PM

When designing a chassis one can measure components with reasonable accuracy, and design elements of the chassis around them. But some components move within the chassis when the car is being driven. Engines move forward under braking, axles can move laterally during cornering. The more vigorous the driving, the more the movement. How much free space should one allow, though? Naturally one would like to be generous but so often being generous in one area means restrictions in others.
In designing my chassis I am considering allowing 20mm between the rear tyres and the trailing arms and maybe 10mm all round the rotating components between gearbox and axle. Is this enough? How about the transmission tunnel for sideways movement and to the front and rear of the engine?
TIA, John


bob - 18/5/02 at 08:53 PM

John
If your worried about a tight fit have a look at the photo archive on locodudes pic of silly power.
And there is a shock absorber in there somewhere!!!!


interestedparty - 18/5/02 at 09:36 PM

That is well tight! Goodness knows what happens to the waste heat. Presumably the car runs out of road well before the ally panels start to melt.
BTW, in my post above, on the propshaft and drive flange I meant 10mm either side and quite a bit more above and below.
John


bob - 18/5/02 at 09:50 PM

John
Cant help you much on the prop clearance as mines not on yet (MK indy).
It certainly looks more than 10mm at the sides though not much more.


stephen_gusterson - 19/5/02 at 12:09 AM

quote:
That is well tight! Goodness knows what happens to the waste heat. Presumably the car runs out of road well before the ally panels start to melt.
BTW, in my post above, on the propshaft and drive flange I meant 10mm either side and quite a bit more above and below.
John



If you are using a live rear axle, then you have to allow for the prop shaft to move up and down with it. If its a fixed diff, then i recon 10mm would be fine as its not going anywhere!

Regarding wheels - the car will tend to roll sideways in a corner, so you need some clearance to cope with that. On my car i gave it a generous 40mm. But im not using a live axle or the trail arms. I hav heard that these can run quite close to the tyre.

atb

steve