At what hp is it time for an lsd?
 

I know this is a hard question to answer because it depends on how good your tires are, but is there a formula or something somewhere that says when you get to a certain hp, no matter how good your tires are...its time to invest in an LSD? My guess is that it would be somewhere around the 300 hp mark. At that point, with our cars being light, you would need one to help with traction, right?

Depends if you're straight line racing or roadcoursing, slicks or street radials.....?



I have a Quiafe, and even at 300whp, it's useless without slicks in a straight line.

It depends on what you're doing with your car and how critical it is that you limit wheelspin. You never NEED one. It would help some at stock power levels. If you're trying to apply power while at maximum cornering force, you would see a real benefit at any power level. If you're drag racing, it would probably be a good idea if you're having trouble hooking up above first gear.

+1 My 60 foot would be waaaaay faster if I could dump the clutch . . . but that is a recipe for spinning a wheel, with basically stock power.

some sticky tires would rid the need for an lsd,



my bfgoodrich kd's stick like glue and never lifts an inner wheel under hard cornering.

We had a couple 240bhp fwd cars with no LSD available in UK, and on trackdays they got blown away by fwd cars with 50bhp less.

Then there was Focus St which had a LSD, but it was set-up for traction, and still cornered very poorly. My other car, Type-R Honda Accord (210bhp, FWD) has one set-up more for cornering, and whilst i can nail it very early in tight bends, it realy struggles for traction from a standing start. To be honest I've never needed it for normal road use, can't get anywhere near fast enough to do so without driving very dangerously. On trackdays however it makes a hell of a difference, a UK performance mag tried one on a renault Clio Cup (190bhp fwd) and went 4 seconds a lap quicker over a 90(ish) second track.

having said that, due to the cost of getting one, I'm not planning getting on in mine, even though I plan on doing trackdays in it.

My 100 HP Civic currently has it's tranny sitting on the floor in pieces. I'm installing a diff. I roadrace though, so I regularly spin my inside tire coming out of corners. Yes, 100 HP is enough for me to pass NSX's on the outside with the suspension setup and Hankook RS3 tires I run.

Cars with a live rear axle greatly benefit from an LSD, they easily lift the back right wheel due to driveline torque.





I guess if your car is prone to understeer or hasn't got any anti-lift in the front, you could make the best use of an LSD.



Get one if you can afford it :)