Scrub radius which image is correct?

[Usr117063]

I take it the first is just displayed more accurate? When you add camber using the strut holes it doesnt effect the scrub radius since its the intercept of the lower joint. But If you were to place the suspension top mount inwards you would effectively being gaining a negative scrub? If it was already completely neutral say.

 

[Tomotek]

All you’ve written is correct mate.. that 2nd pic is terrible!

 

[Usr117063]

The internet is a host of the right and wrong information ?

 

[Tomotek]

Isn’t it just!!.. don’t have to have any knowledge to write about anything... caster angle/ mechanical trail is the other factor in steering feel/weight... like scrub radius but looking side on to the car

 

[Usr117063]

I was just about post about adjustable top mounts with increased castor. So ever so slightly the scrub radius has changed (more towards negative?) But the mechanical trail has moved forward. So If I ran this sort of thing I would not only give more castor but get back to the standard trail?
https://www.pure-motorsport.co.uk/c...ion/clio-2-rs-roll-centre-correction-kit.html

 

[Usr117063]

Forget the 2nd thing I said ? Still learning about car dynamics, just trying to put it into play for real

 

[PhillipM]

As said. it's the first one, upper strut mount to balljoint, your kinematics are always to pivot points.

 

[Usr117063]

Any easy ish ways of checking what it is? I thought about taping around the wheel and putting a post up aside the car where Ill have a couple of make s**t arms that hover over and under the joints, mark around the post so when I move the car Ill put string or stick along the 2 points touching the ground.

 

[Tomotek]

This is no real easy way to measure it.. I’ve modelled the front end in CAD though, so can work out the standard geo, then move the top mount and tell you what it would work out at. [emoji1360]

Sent from my iPhone using Tapatalk

 

[Usr117063]

That looks great! Better than string :S

My castor is set to 4.75 and 4.69 o/s. Although I have increased camber via the wishbone bushes which Im guessing is a 5mm increase of track width. I was thinking about the variables because wouldn't even the ride height change the numbers? I know some of this is so small but it makes difference regardless of how much.