How much does Toe affect straightline speed?
10-27-2010, 01:44 PM
#1
Drifting
Thread Starter
How much does Toe affect straightline speed?
If you had to quantify it, how much affect (in MPH) would 1/4" total toe-in the rear of a car have vs. 1/8" total toe-in the rear?...on a 1 mile straight away for instance...
Does the toe-out in the front of the car hurt speed more or less than the toe-in in the rear? or are they the same?
Trying to figure out if its really that big of a speed scrubber, or something negligible.
Thx
Does the toe-out in the front of the car hurt speed more or less than the toe-in in the rear? or are they the same?
Trying to figure out if its really that big of a speed scrubber, or something negligible.
Thx
Last edited by throwit; 10-27-2010 at 01:46 PM.
10-28-2010, 11:17 AM
#3
Racer
if I got some time in Dec to go run the car in some DE sessions later on sun, I'll crank some additional toe out up front and measure the backstraight sector times compared to the the other data taking that day
time through sectors is what we'd want to see (ET)
time through sectors is what we'd want to see (ET)
10-28-2010, 02:20 PM
#4
Melting Slicks
It's pretty much second order, not any real measureable effect in the speed range we are talking about here.
I set up a Renault Cup Appliance way back when and I calculated the torque on the front wheels at 3/4 of the straightaway, then we tilted the trailer up to get the same pull load on the front wheels, left it in first gear and worked the toe to zero. Not sure if it helped, but the idea was with a car that had no power you wanted the toe to be zero at high speed with the effect of power on the suspension joints. If you have no power (like an FV or the Appliance) then it might make some difference. With a powerful car set the toe to where it works best on the corners and carry more speed onto the straights. That's probalby more important than drag effect anyway. If you carry 1 mph more out of a corner and carry it all the way down the straight that's a big deal.
I set up a Renault Cup Appliance way back when and I calculated the torque on the front wheels at 3/4 of the straightaway, then we tilted the trailer up to get the same pull load on the front wheels, left it in first gear and worked the toe to zero. Not sure if it helped, but the idea was with a car that had no power you wanted the toe to be zero at high speed with the effect of power on the suspension joints. If you have no power (like an FV or the Appliance) then it might make some difference. With a powerful car set the toe to where it works best on the corners and carry more speed onto the straights. That's probalby more important than drag effect anyway. If you carry 1 mph more out of a corner and carry it all the way down the straight that's a big deal.
