Zero Bump Steer

[Matt49]

I know this is something that pavement guys aspire to. To put it modestly, I don't think most dirt cars are built/designed this way "out of the box". But is that a crutch or do we really have a need for the amount of bump out that is "built in" to many front end geometries?

[7uptruckracer]

We have a lot of Ackerman too...I've seen anywhere from .020 to .065 on the RFs and always pretty close to 0 on LF I feel it helps with stability without causing excessive heat and darting a lot of static toe can cause on straightaways, that's my thinking. Now what's right in the RF these days I dunno. On asphalt we go zero because we load so much on bumpstops we limit bump and Ackerman to zero so it doesn't abuse tires, we also generally run longer races on a weekly basis, but it's for a wear reason on asphalt.



I know this is something that pavement guys aspire to. To put it modestly, I don't think most dirt cars are built/designed this way "out of the box". But is that a crutch or do we really have a need for the amount of bump out that is "built in" to many front end geometries?

[RCJ]

I think it's the different tires.Dirt tire is 90" at 12lbs ,and a lot of us are on 55 compound.When I raised my rack I shot for less than .008 per inch toe out, over 6'' of travel.Alot of work and expense to get there.Several people have driven my car.Drives good and drives like a new car are common responses.At the same time I find myself running more static toe and have trouble getting heat in the front tire.

[7uptruckracer]

See that's what I'm talking about....it's common if we have a qualifying to add a shim on the LF on asphalt to get heat built rapidly using bumpsteer,

QUOTE=RCJ;1995351]I think it's the different tires.Dirt tire is 90" at 12lbs ,and a lot of us are on 55 compound.When I raised my rack I shot for less than .008 per inch toe out, over 6'' of travel.Alot of work and expense to get there.Several people have driven my car.Drives good and drives like a new car are common responses.At the same time I find myself running more static toe and have trouble getting heat in the front tire.[/QUOTE]