Originally Posted by
dvaid852456
So if roll increases it doesn't automatically mean the weight transfer does. If I increased front droop and created more body roll towards the rear I may have to increase the rear spring rate to push back against the body roll and thus increase weight transfer at the rear and ADD grip?
Does roll increase grip or is it weight transfer? Or neither or both
"a net reduction of traction due to the increased weight transfer" - I always thought an increase in weight transfer was putting more weight over say the rear wheels and giving them more grip. I also thought body roll was the action that added that extra weight. If body roll doesn't add the weight over the wheel and is the opposite to weight transfer why does body roll increase traction such as in the example of the trophy truck?
I am struggling to wrap my head around this but thanks for the replies so far. I just think if I can understand it a little better my setup skills will improve.
The term "Roll" is usually only for between left and right. Use the term "weight transfer" for front vs rear. This might have confused you when you read some articles.
Weight transfer from F to R or vice versa gives that end more grip like you said.
But weight transfer in general decreases overall grip. Think you can't really drive your car when cornering as fast as when you go straight. e.g. static overall grip is 200lb. when it's rolling, it becomes 180lb. Hence less overall grip.
Body roll increases traction. But what you're missing here is that the statement is talking about "relative" traction. e.g. more roll in F than R. Then more traction in F. Vice versa. Yet again, overall available grip decreases because of weight transfer.
All in all, the less weight transfer the better. Amount of weight transfer is determined by CG height, track width, and weight of the car. Proportional to CG height and car's weight. Inversely proportional to track width. This is why you try to make the car as light as possible, as low as possible and as wide as possible. To add another note on this account, the less droop decreases weight transfer between F and R. This prevents horribly (or unexpectedly) pushing or over rotating car on and off throttle respectively. Generally speaking, because of this, with acceptable grip on road surface, less droop is almost always better. The "less" droop is relative term though