Thank you Onasled Racing and TSW...

[M^Cubed]

Keep us updated about the spring choice. I'm holding off on installing mine until I hear a little more about this.

[Nathan]

Originally Posted by Bimmer Lite

Stock suspension before. Lap times? No, sorry I do driving schools and not timed events.

- Marc

I can understand the purity and no timing devices rule for an HPDE but we still keep a watch on each other at least informally in the paddock. Otherwise it's hard to see progress.

[Ryephile]

Congrats on the TSW/KW V2 setup It looks like Greg really took care of you. I like his corner weighting "plates" so there's easy access to drop links and spring perches. That is strange your 500Lb/In were wonky out of the box. That is strange coming from KW. Perhaps they picked the wrong item off the shelf. You should be able to reference the silk-screened part number on the spring with KW's race catalog.

Your spring rates, sway bar choice, and driving impressions certainly align. For those wanting a more neutral setup would opt for same spring rates front & rear with the same RSB. For those wanting to run stiffer swaybars [like H-Sport Comp front & rear] to make highway cruising more comfortable and get the same dynamic wheel rate would opt for 400Lb/In front & rear. The reason different coilover solutions offer varying spring rates has everything to do with their intended purpose and the anti-roll bars they choose to use with them.

The R888 should handle HPDE's just fine; it's what they're made for! While I haven't run them personally, I'd assume hot pressures of 42 aren't way off base. To keep the rear end in-check, I'd opt to run a few PSI less in back. Next time out, play with the pressures, but initially shoot for something like 39 hot front and 36 hot rear. That is a bit less than where I start with my Hoosiers, which typically need a bit more pressure than other tires.

Cheers,
Ryan

[Bimmer Lite]

Originally Posted by Nathan

I can understand the purity and no timing devices rule for an HPDE but we still keep a watch on each other at least informally in the paddock. Otherwise it's hard to see progress.

Yea, I see that, but I'm just not into it. Weird, right? There are so many variables in a driving school environment that I'd doubt you could find an accurate lap time to go on anyway, especially from someone holding a watch in the paddock! And you're right - it's not the spirit of the event.

And I guess this comes down to our definitions of "progress." If that = lap times for some, then that's cool. If that = trying and being able to do different lines, techniques, etc..., then I guess that's cool too.

You won't see any video cameras in my car anytime soon, either.

- Marc

[Bimmer Lite]

Originally Posted by M^Cubed

Keep us updated about the spring choice. I'm holding off on installing mine until I hear a little more about this.

Will do. If I were you, I'd start asking around. It also depends on your ultimate goals - are you looking for a dual-purpose car, or do you think it'll be a track car at some point? Also, how do you like the car to handle? For me, I'm very comfortable with the tail being twitchy. One thing to remember is that the MINI's suspension is NOT balanced out of the box - it understeers like a pig, right? I hate that, so I wanted to do what I could to balance it. My car is not dangerous by any stretch of the imagination. I definitely could have gone for stiffer springs all around and even stiffer rear springs. To the point, I had one session in a monsoon - the entire track was standing water - and the handling was as predictable as it was in the dry. Understeer for ham-handedness, and oversteer for ham-footedness (abruptness on/off the brakes, in turns, etc...).

Not that racing is a realistic goal for most, but I wonder what we'll find if we can get the spring rates for FWD racecars like the Koni Civics, MINIs, Acuras, etc...

Edit - that reminds me of something Randy Smalley said about his racecars' rear sway bars: they couldn't buy one stiff enough, so they had to make it themselves.

- Marc

[Bimmer Lite]

Originally Posted by Ryephile

Congrats on the TSW/KW V2 setup It looks like Greg really took care of you. I like his corner weighting "plates" so there's easy access to drop links and spring perches. That is strange your 500Lb/In were wonky out of the box. That is strange coming from KW. Perhaps they picked the wrong item off the shelf. You should be able to reference the silk-screened part number on the spring with KW's race catalog.

Your spring rates, sway bar choice, and driving impressions certainly align. For those wanting a more neutral setup would opt for same spring rates front & rear with the same RSB. For those wanting to run stiffer swaybars [like H-Sport Comp front & rear] to make highway cruising more comfortable and get the same dynamic wheel rate would opt for 400Lb/In front & rear. The reason different coilover solutions offer varying spring rates has everything to do with their intended purpose and the anti-roll bars they choose to use with them.

The R888 should handle HPDE's just fine; it's what they're made for! While I haven't run them personally, I'd assume hot pressures of 42 aren't way off base. To keep the rear end in-check, I'd opt to run a few PSI less in back. Next time out, play with the pressures, but initially shoot for something like 39 hot front and 36 hot rear. That is a bit less than where I start with my Hoosiers, which typically need a bit more pressure than other tires.

Cheers,
Ryan

Thanks! There was an odd marking on the springs that seemed to show a range of rates; I think at the end of this we are going to find out that they just put the wrong springs in there as well.

Yea, the R888s represent a new learning curve for me.

One thing I haven't quite grasped yet is what the best way is to go about adjusting the V2s for performance. Greg set them to near the middle range, and it was a bit bouncy. I stiffened the rear to 3 clicks from full stiff and the front to 5 clicks from full stiff. I liked this better since oversteer was quicker and less dramatic.

The adjustment is just for rebound, correct? Any tips?

And sorry for the multiple posts to respond to quotes - when I press the multiquote button it doesn't insert the material, or perhaps I'm doing something wrong.

- Marc

[Ryephile]

Hey Marc,

Since TSW and KW valved the meat of the damping curve for the 60 N/mm springs they normally include with the V2's. As such, your much stiffer springs will require significantly more rebound damping. I would take TSW's recommended setup sheet and go a handful of clicks harder on rebound to start with. Yes, the adjustment on the V2's is for rebound only. From what I've gathered it should be broadband rebound, meaning both high and low speed. It sounds like you've changed the rebound to be pretty close to the hard end of the scale, so I'd guess that you're pretty close to where you need to be.

In the seat, the car should never feel bouncy nor sharp/jolting. There will be a happy medium where the spring rate will be critically damped by the damper. It will feel firm [especially with your 500 Lb/In rear spring] but not bouncy or jolting. Bouncy means you need more rebound, and jolting or hammering means you have too much rebound. Find those bookends and then center it.

The KW race springs should have markings something like "80-170*" and "90-140*" for you, assuming they're the same straight-from-the-catalog of KW Competition just like I have on my TSW/KW V3's. The first number is spring rate in N/mm, and the second number is free length in millimeters.

Cheers,
Ryan

[cct1]

Marc,

When you get a chance, could you measure your ride height on all four corners on your track tires (BTW, --since you're corner balanced (and I'm not), I'd love to see where you ended up for my own personal selfish reasons. Which size 15's on the Toyo's did you end up with--225/45 (that's what it looks like in the picture)?

I love the setup too--my springs aren't as tight as yours, but it's really a nice setup. I may have been too low to begin with, I raised up a bit, now I'm too high, car felt much better lower...I really need to get to a good suspension shop!

[Bimmer Lite]

Ride height, according to Greg's documentation that came with the car after install:

Front: 3" from bottom of jack pads
Rear: 3.75 from bottom of jack pads

That's with the track tires (225/45/15 R888).

I refuse to mess with ride height on my own because it seems to me that it would then change the alignment settings which I am not equipped to manage/change/check on my own. So the ride height stays. I should also mention that Greg shimmed the inner ball joints to keep the roll center in-tact.

I feel great about going with TSW's setup - I wish the springs would have worked out, but the Hypercoils dynoed as well as a set of good KWs would have, so I'm not too worried about it.

- Marc

[Bimmer Lite]

Originally Posted by Ryephile

In the seat, the car should never feel bouncy nor sharp/jolting. There will be a happy medium where the spring rate will be critically damped by the damper. It will feel firm [especially with your 500 Lb/In rear spring] but not bouncy or jolting. Bouncy means you need more rebound, and jolting or hammering means you have too much rebound. Find those bookends and then center it.

Thanks, that's what my behind told me - that the stiffer setting was actually more compliant and better behaved. There was a high line available through that bulb that a lot of cars were taking (and then diving down to the apex), but my car hated it because it was bumpy up there. After I stiffened the shocks, it was fine up there, but definitely felt quicker on a lower line. Well, I don't know if it was quicker, but I was carrying more speed there which = 5-8 more mph at the end of the straight. Don't yell at me - I wasn't looking at the speedo, it was my instructor!

- Marc