Hey guys, Trying to figure out a good spring rate to run on Moton Street Sport coilovers on 140ug-rcomp tires on fairly smooth tracks. Wheels are 15x9 front and 15x8 rear. Research so far points to stiffer in the rear possibly an 8/9kg setup, but other people have been telling me to go much stiffer. The car is not fully stripped (rear interior, bucket and no crash bars / airbags) and has a back half cage. The car is not street driven also.. Any advice on where to start?
I advise you to post pictures of your MINI ASAP. In other news, what year MINI? S or Justa? I run 8 front/9 rear on my street/track toy 2003 MINI S with KW V3 coilovers, and I'm very happy with the setup. For pure track work, you could go to a 10/12 setup unless the track is really rough - and provided the Moton Street Sport coilovers are valved to work with springs that stiff (no slam against Moton of course, I'm just not familiar with them).
What spring rates are your Motons tuned to? Stiffer springs tend to be better but if you run too stiff for your shocks then you will have bad handling maners for sure. So try and find this out. Good thing is that there are several top shock tuners that will re-tune if needed. Also need to know what sway bars you are using. It matters. What camber adjustments are you thinking of using also. ?
We are working with the Canadian distributor for Moton so we have the ability to have them valved to which ever spring rate we choose so far which is a great help! Rear swaybar is a H-sport 25.5 hollow bar on the middle-softest setting (track dependent) with adjustable end links front and rear, and a stock front swaybar. For camber we are thinking of starting with -3.5* front and -2* rear then adjusting it from there based on test and tune results, any recommendations for a good baseline setup to begin tuning from? Will post some pics soon! it is an 03 S without sunroof. Thanks for the help so far!
Also does anyone know the motion ratio for the Mini rear suspension so we can do the calculations on a good rear spring rate?