Bump steer data


N

NLek

Member
Joined
Aug 11, 2013
Messages
132
I'm looking for stock front bump steer data of preferably type r ek9 or dc2 or else any 5th or 6th gen model. Actually I have found the toe curves of a 5th gen through honda sources but they only show the curve but no data along so it doesn't say exactly how much bump toe out and droop toe in per travel.

Maybe somebody with advanced suspension experience and bump steer gauge has ever meassured stock bump steer before they made changes to their geometry?
 
Last edited:
I did some meassuring on a lowered ek3 with stock geometry which has same wishbones and knuckles as ek9 so it is a good reference.

Result, the toe curve is completely lineair in both directions. Toes out on compression and toes in on droop at about 0.02mm per cm of travel
 
I had roughly measured the geometry of all the arms and pickup points and modelled the front end in 3D CAD, constrained such that it could be bumped, rolled and steered to measure the camber and toe angles.

Wasn't major accurate because I only measure using a tape measure on a roadworthy car on the driveway, but I recall seeing something similar what you found in pure bump.
 
Nice! I think I ever came across a post of that on Honda Tech if I'am not mistaking.

Not many civic drivers have been in this territory yet. :)
 
Yea there was indeed a fairly long discussion centered around er... roll centers. Excuse the unintentional pun.
 
Is that completely linear all the way through suspension travel?
Extreme e.g
your car is super low, reset toe to zero at rest, it will still remain 0.02 per cm of bump?
So in this respect having the car "on its arse" wouldn't effect the bump steer negatively?
 
No I should think that would be highly unlikely.
 
jesse888 said:
Is that completely linear all the way through suspension travel?
Extreme e.g
your car is super low, reset toe to zero at rest, it will still remain 0.02 per cm of bump?
So in this respect having the car "on its arse" wouldn't effect the bump steer negatively?
Click to expand...

It was lineair on the EK3 with about 5cm lowering and travel meassured from 2,5" compression to 2" droop......putting the car back to stock rideheight would mean it first toes in a little bit, which after you correct to zero gives slightly shorter tierods which also give slightly different arc. It could well be that 5cm of lowering brings the car in a sweet spot with regard to the bump steer curves. That is if the geometry remains stock.......if for example you change your camber all arcs will be different.
 
You must log in or register to reply here.
Back
Top