Can anyone recommend a good article on tuning adjustable dampers? Or write one in the replies? I have rebound-adjustable KW V2 coilovers, and I'm curious on how to tune the adjustable dampers. Currently, the car feels great in the corners, but it tends to bob and bounce on the highway. If 0 is full hard and 18 is full soft, I was running 12 on the street and 9 on the track. The bob was bad on the highway, so I tried the track settings on the street, but that didn't really fix it. I drilled the body over the rears, so I can pull the trunk access panels and make adjustments. Any ideas?
A basic tuning guide http://www.vorshlag.com/documents/Tuning_AST_Shocks.pdf An article about bump travel Suspension Bump Travel & Stack-up Height - Vorshlag LLC. I added this article, because KW springs sag quickly, and KW spring rates are notoriously inconsistent. There is also a tendency for users to lower the MINI without increasing spring rates, which reduces available bump travel. Be aware increasing spring rates beyond 25% on a KW shock may exceed its damping range. An illustration graphing the shock cycle over a bump Real World Critical Dampening. This may or may not help in understanding the effect damping has on "bob". KW shocks other than the high end remote reservoir models have short service life. It could be time for a rebuild; blown seals are not the only indicator a shock needs service.
I can’t address what may be problems with the shocks. If you are looking for a good shock tuning article I would suggest the tuning instructions in the Bilstein Catalog. Basically the article says if the car Is pushing, increase the rear rebound. Work on the opposite end rebound.
If you increase spring rates get a good set of Swift Springs? Below is the "custom" spring info you need on the TSW / WMW KW V2 coil overs. Front Springs: 60mm ID, 200mm length (8"), 6kgf/mm (336 lb/in) spring rate Rear Springs: 60mm ID, 140mm length(6"), 6kgf/mm (336 lb/in) spring rate I have hem also.:wink: and the TSW now WMW "custom" KW V2 specs can be found on the NAMless site.:ihih:
Here's a nice little article I came across when researching what spring rates I should be using. The Consummate Driver - How to Choose Spring Rates The pertinent quote for this topic; " It is important to note that you want your rear SF to be slightly higher than your front otherwise the car might start to porpoise; rock forward and backward." For an R53 (eyeballed with ruler): D1 = 10.5" D2 = 14" Spring Angle of 5 degrees is close enough Unsprung weight of 80 lbs is close enough Other weights get from your corner balance sheet.
Just in case some may see higher rear SF as a one-size-fits-all solution, higher rear SF for a level highway ride does not automatically translate to better track performance. FYI example of higher rear SF for autocross use, Autocross to Win (DGs Autocross Secrets) - On FWD.
Dave you have the V2's with Swift springs? Did you stay with the KW specs for the springs, or did you go with a stiffer spring? My rear springs aren't in the best of shape, and this is one of the winter projects.
I did not get the Swift springs yet....they are also going to be my winter project. I have been kicking around with 400 front / 450 rear.
If adjusting the shocks isn't changing the handling the shock could be bad. Best way to check is set to full stiff and then full soft and note the difference. If the shocks are good. Then start in the middle all the way around and then adjust The rear stiffer till the car starts to oversteer. If you have to much body roll adjust the front stiffer this will also reduce oversteer. Best springs to start with on the R53 are 450f 550r. Ok street ride good on track.
Pushing this thread up some. But would increasing the spring rates this much cause issues with the dampers if they are not specked to that rate? I am not super thrilled with my standard KW V2 springs. I have no idea on the rates for the Progressive front spring. But I recall KW telling me that the rears are as low as 230lbs?! I want a stiffer spring all around but worried about hurting the valving?
The stiffer springs should help your shocks since they won't be used as much as they are with the crap stock KW springs. I replaced mine with Swifts 400 front and 450 rears and my car is perfect now. I had a lot of fun at the Dragon this year with my older WMW TSW Custom KW V2 setup with my new Swift springs. I also let a few people I trust (Colin, Mendra and Eric from Helix) take my car out for runs and they all came back smiling from the suspension set up. Eric from Helix came back and said WOW he did not push it really super hard because it was not his car and he was on public roads but he loved the set up. Very well balanced. My KW V2's are set at 12 front / 10 rear with Swift 400's front 450's rear. This is by far the best setup I have had on this car. All I have to do is point and go.
Awesome great to hear good sir. I am looking forward to getting this right. Sorry to hit you up with some many questions, but what ID are the swift springs? I think KW is 61mm?
I talked to the guys at TSW when they were still in business. This was long before Way / WMW bought TSW and the rights to the TSW spec'ed custom setup for the KW's. The real original TSW custom set up was KW V2's with Swift springs but KW convinced the TSW guys they could provide the same spring as the Swifts. (They failed and have never even come close) They are 60 mm ID for the stock KW or the Custom ones. The only thing "custom" is the valving and the crappy soft KW liner 336lbs springs. (Too soft) Here is the older info. and V2's and V3 have the same custom valving. The only difference between the two in the added adjustability of the V3 which are not needed for the street. All the info you could ever want on the Swift springs can be found below. Swift Springs USA KW Variant 2 & 3 "TSW spec" Coil-over System for 2002-2006 R50, R53, MINI Cooper and Cooper S, and 2005-2008 R52 MINI Cabrio. This is not the off the shelf KW V2 or V3 coilovers you buy just anywhere. This is the TSW spec KW V2 & V3's. These have been resprung and spec'd with new linear rate springs. TSW did a lot of testing to match a set to the handling and weight of the MINI, making something just perfect. It comes complete with 60mm springs and perches selected specifically for the MINI and also mates up perfectly with Vorshlag 60mm camber plates. Like all KW coil-over systems the strut bodies are all stainless steel with stunning eye appeal.
So my sagging KW V2 springs are stiffer than I thought, they feel softer than that, but I couldn't remember the specs offhand either. I wonder how stiff you can go on the springs and still be within earshot of the custom dampers. Decisions, decisions.
Seems like the rule is 30% higher or lower rates than what are supplied are ok for the dampers. So for us with standard V2s the highest recommended is a soft ass 300lbs!
If the TSW V2's are set at 336lbs, then where Dave is at should be just about right, it's right at 30% higher--I have the TSW KWs/springs, so I might just go with Dave's set up. Although they really don't feel 336, I'd have guessed lower. I'll eventually probably just go all out and get the JRZ's; the ability to increase castor is so tempting.