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Driveshaft Material Stress Calculation

Posted: Thu Mar 31, 2005 4:47 am
by MD
I am back on my hobby horse again.

I need the aid of a mechanical engineering type.

I would like to know how much torsional stress our driveshaft would experience coming from an engine with say a maximum of 300 flywheel horsepower.

Knowing this figure, we would then need to find a tube material as light as possible that would also be capable of maintaining form if the same forces were applied.

Once we had this type of data, we could then commence to experiment with different drive couplings and see which type worked the best at eliminating the donuts.

It would also be handy to know what maximum rotational speeds CV joints can handle?

Apart from Kevlar, what other materials would be suitable based upon the actual calculations?

I should have paid more attention in my maths classes instead of perving on the teachers boobs. Maybe I would know the answer by now. :wink:

Any takers?

Posted: Thu Mar 31, 2005 5:58 am
by Mats
You don't need someone that is good with numbers, you know someone with hands-on experience...

Difficult stuff.

Posted: Thu Mar 31, 2005 7:33 am
by Jim K
The late race 75T's had this composite one-piece driveshaft with U-joints. For numbers, assume a worst case scenario with slicks on a smooth track, when you're trying a drag start with 68kgm of torque (thats how much the A1 class 75T had!!). You have length, OD and you will accept U-joints. With this info, all you have to do, is give that specialty shaft company a call, asking for details and a price. Make sure you're sitting on the bed when you ask them...!! You don't want to fall and hurt yourself! (or die laughing, it depends how you take it!) :D Who knows, they may even live up to their name:...Shaft company, hahah!!
Jim K.

Driveshaft

Posted: Fri Apr 01, 2005 6:02 am
by Reale
My 3" CF driveshaft is rated for more than 700 ft/lbs of torque. It actually could have been made out of thinner stuff, but had to be 3" to take the fittings at either end.
I am still looking around for the CV joint solution, but these folks:

http://www.acpt.com/driveshaft/driveshafts.html

have dealt with driveshafts turning at engine RPM.

-Al

Posted: Fri Apr 01, 2005 7:16 am
by Mats

Drivelines

Posted: Sat Apr 02, 2005 4:43 am
by MD
Thanks guys.

I have made contact with both companies provided in your links and will await feedback to see if anything develops. GKN apparently have an Australian connection which could be a bonus.

Posted: Sat Apr 02, 2005 5:42 am
by TNT
Hi :D
I would also like to know where is the problem with the transaxle and it has horsepower fobia, is it only the shaft and the donuts, it is the gears that have the problem or the 'box' itself can't take the extra power :?: I am saying that because i have seen many cars with much more power than stock and having less problems than the transaxle without modifications.
Anyone? any ideas :idea: :?:

Driveline

Posted: Sat Apr 02, 2005 8:40 pm
by MD
For the price of a local phone call, why not contact JimGreek in your home town. I am sure he will help you out in your own language as well.

Posted: Sun Apr 03, 2005 12:43 am
by Mats
Maybe he's in Köln? ;)

Posted: Sun Apr 03, 2005 3:43 pm
by TNT
:lol: You got me on that Mats !

Well MD i don't have a car at the moment i just putted my thoughts here because u meantioned something about 300hp :D :D and i think maybe the shaft is not the only one to have a hard life after this mods.For me now this is more of a philosophical conversation (because i dont own a car :cry: ) very interesting though, so i wont bother JimGreek with my inquiries (i think his is realy busy modifying his Alfas :o ) .