1.9 Driveshafts

[vickiw106 1]

As above really.

 

I have search for the answer and drawn a blank

 

I have a 1.6 rally car that hopefully when I put it on the rolling road on Tuesday will be putting out about 160bhp. (Not sure on torque yet about 200 ft-lb I hope)

 

What can 1.9 shafts take?

 

Any advice/thoughts would be appreciated

 

Thanks

Ian

[Tom Fenton 1,542]

I think you'll be lucky to see 200 ft-lb but that is beside the point.

 

1900 shafts will deal with that kind of power, but really it is any shock loading that will kill them, so wheelspin etc. I'm guessing it is a competition car so treat them as a service item that will need replacing every so often and you will not go far wrong.

[vickiw106 1]

I think you'll be lucky to see 200 ft-lb but that is beside the point.

 

1900 shafts will deal with that kind of power, but really it is any shock loading that will kill them, so wheelspin etc. I'm guessing it is a competition car so treat them as a service item that will need replacing every so often and you will not go far wrong.

 

 

Sorry ignore me I meant compression not ft-lb

[Cameron 16]

Grab a calculator.

 

Torsion Wiki

 

Don't be scared off by the funny symbols and scary equations, it's actually a lot simpler than it looks. You want to use the second equation down and fourth equation down.

Edited April 7, 2010 by Cameron

[Cameron 16]

Based on low carbon steel and a safety factor of 3 you'll be able to get away with 230Nm through a 1.9 driveshaft.

[Chris H 10]

Been running 309 gti shafts with a 200bhp 16v engine fine...never broken a shaft, did break a cv joint once when using full throttle in 1st comming out of a hairpin abut thats one faliure in 7years!

[Baz 421]

Equally, no problems here upon various modified cars >200bhp.

[brumster 135 1 Cars]

I've been putting ~180ft.lb through 309 shafts (10mm longer than 205 gti shafts) without any problems, and I know others who have been doing the same, in competition use. IMO, it's all about how and when you squeeze that throttle pedal. If you're the type o'gal who likes hammering it full throttle out of hairpins on full lock, then any driveshaft (let alone a 1900) is going to have a hard time of it provided you're easy on it and only go for full throttle when you're more or less straightened up, you should be fine with 1900 shafts. Also depends how much wheelspin you get.

[Tom Fenton 1,542]

It is the CV joints that are the weak point as others have said. I've been putting 205ft lb thru mine. As I said, treat the CV joints as a service item and you won't go far wrong.

[vickiw106 1]

I've been putting ~180ft.lb through 309 shafts (10mm longer than 205 gti shafts) without any problems, and I know others who have been doing the same, in competition use. IMO, it's all about how and when you squeeze that throttle pedal. If you're the type o'gal who likes hammering it full throttle out of hairpins on full lock, then any driveshaft (let alone a 1900) is going to have a hard time of it provided you're easy on it and only go for full throttle when you're more or less straightened up, you should be fine with 1900 shafts. Also depends how much wheelspin you get.

 

thanks for all you replies

 

 

by the way brumster you doing mira next saturday

 

thanks

ian

[brumster 135 1 Cars]

Yep, we'll be there, provided I fix the master switch this weekend :-S !!

 

You there too? Competing?

 

edit : Never mind, got off my lazy arse and consulted the entry list - I Williams at car 38 I assume

 

Tom's right, of course, by "driveshaft" it's really the whole caboodle you're interested in, and it's normally the outer CV's that go, not the shaft itself.

Edited April 9, 2010 by brumster