Suggestion: contact other Honda converters and ask if they addressed bump in their builds??
| ausmini https://www.ausmini.com/forums/ |
|
| Bump steer https://www.ausmini.com/forums/viewtopic.php?f=2&t=97301 |
Page 1 of 1 |
| Author: | Dan81 [ Sat Jun 02, 2018 9:37 pm ] |
| Post subject: | Bump steer |
Hi all, new to the forum. Just want to find out if anyone knows, or can measure, the amount of bump steer present on a std suspension setup. Thanks. |
|
| Author: | Bill B [ Sun Jun 03, 2018 10:52 am ] |
| Post subject: | Re: Bump steer |
Do you mean the change in amount of toe-in and toe-out of each front wheel as it moves up and down through its suspension travel? |
|
| Author: | Dan81 [ Sun Jun 03, 2018 6:42 pm ] |
| Post subject: | Re: Bump steer |
Yep that's it. Putting a honda engine in and have had to move the steering rack. Need to prove to engineer bump steer isn't any worse than original. Wasn't switched on enough to measure before I changed the mount. |
|
| Author: | Harley [ Sun Jun 03, 2018 7:38 pm ] |
| Post subject: | Re: Bump steer |
There's no specific measurement for it that applies to all minis as there were different length arms and racks depending on production year. The other influence is ride height. What i would do if i was you is put the rack in its stock location (or simulate) and take the measurements you need at the correct ride height then position it to where you will finish the rack and re-measure. What wheels, brakes and hubs / arms are you running? How far did you move the rack? |
|
| Author: | Dan81 [ Sun Jun 03, 2018 9:48 pm ] |
| Post subject: | Re: Bump steer |
Have moved the rack down the fire wall 20mm. The car is a mini k, so Mk1 steering arms I think, has disc brake hubs, adjustable lower arms, steering rack is new from mini spares for Mk2. Will have to see if I canmock up the original rack position. |
|
| Author: | low n blown [ Mon Jun 04, 2018 8:38 am ] |
| Post subject: | Re: Bump steer |
Dan81 wrote: Have moved the rack down the fire wall 20mm. The car is a mini k, so Mk1 steering arms I think, has disc brake hubs, adjustable lower arms, steering rack is new from mini spares for Mk2. Will have to see if I canmock up the original rack position. I can see his concern, particularly if you lower the suspension height. I can almost guarantee this has increased your bump steer. In the sports sedan we lifted the rack to reduce bump steer to good affect. You have unwittingly gone the other way. |
|
| Author: | 9YaTaH [ Mon Jun 04, 2018 10:51 am ] |
| Post subject: | Re: Bump steer |
Suggestion: contact other Honda converters and ask if they addressed bump in their builds??
|
|
| Author: | fuzzy-hair-man [ Mon Jun 04, 2018 10:52 am ] |
| Post subject: | Re: Bump steer |
There's geometric models for understanding virtual centres, and from these roll centre, and bump steer. Put very simply if you draw a line from where the upper and lower ball joints pivot through the pivot for the upper and lower arms, where these two lines intersect is the virtual centre. To have no bumpsteer at a particular suspension height the steering linkage from the steering arm to the rack should also point at this virtual centre. If you've moved the rack down 20mm my brain is telling me you'd need to move the steering arm down more than 20mm to compensate. Project binky had a bit where they delved into bumpsteer which is probably worth a look. Here's some stuff on finding virtual centres called virtual pivots in this article, http://www.autospeed.com/cms/article.ht ... n&A=112911 |
|
| Page 1 of 1 | All times are UTC + 10 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|