Rolling road

[Steve_Farrimond]

Went to the rollers on Saturday see blog if interested;

 

http://forum.wscc.co.uk/forum/index.php/blog/20/entry-57-engine-setup/

 

 

[Norman Verona]

16% reductio due to transmission loss maybe a bit conservative. With a LSD it can approach 30%.

[Terry Everall]

30% seems a bit high Norm! even with a LSD

[Norman Verona]

Up to 30%. I've seen evidence of 26% when an engine was dyno'ed then, after fitting was RR'd. Wouldn't take much more friction to get that to 30.

 

Anyway, 16% is conservative.

[Terry Everall]

Lets agree on 23% then as a half way house

[Norman Verona]

OK. 50% more than 16%  

[Ian Podmore]

I'm being thick (maybe) but why would an LSD increase the transmission losses?  It only prevents slip between the axles so if both axles are rotating at same speed where do the additional losses come from?

[Norman Verona]

Because they're high friction as the plates are in contact. Roger King reckons that a normal set of gears and an LSD can reduce power at the wheels by up to 30%.

[peterg]

Is that orange line on the graph supposed to be the torque reading?

It appears to show a max of 303 lb ft... if so, it's bollix, unless of course it's a 2 litre turbo diesel ;-)

[FILFAN]

What about a helical LSD

[Dave Eastwood (Gadgetman) - Club Chairman]

Or viscous?

[dombanks]

its AB near chester. great place ive been there a few times for stuff. im guessing they did the dyno run in 3rd gear so the graph for torque will be wrong wont it?

[dhutch]

Roger King reckons that a normal set of gears and an LSD can reduce power at the wheels by up to 30%.

Still unsure about this.

[Steve_Farrimond]

its AB near chester. great place ive been there a few times for stuff. im guessing they did the dyno run in 3rd gear so the graph for torque will be wrong wont it?

That's the one. 3rd gear, I think it's 5th for the torque figure, am I right?

[robo1968]

What about a Quaife ATB LSD?