I have an 04 MCS. So far I have camber plates and lower rear control arms with 15x7 K1's. I've done ok in SM with street rubber but I want to jump to R compund for this season. The question is are coilovers worth the extra money over koni Yellows/springs? The car is my daily driver (20K an year), but I autocross 2 or 3 times a month so that's important too. If coilovers are the way to go, what can I expect in the way of additional maint and maint cost?

 

Tires
Just yesterday we had autocross and one of the MINIs that usually has R compound tires was using Goodyear Eagle F1 GS-D3 street tires. I think he gave up about 2 to 3 seconds on a 30 second course due to the tire change which is huge. He wasn't used to driving them for autocross so that didn't help. I have driven in street tires at the end of an autocross faster than I have driven during the event with R compounds so there can be some overlap of times based on driving skill.

Basically in SM class you have to use R compounds with the best options being Hoosier A6 or Kumho V710. Some drivers can make tires last but there are two things that will limit the life of the tires, one is time as rubber hardens over time and the other is heat cycles. I find that about 6 events or about 40-60 runs is about it but it will depend on what level of competition you face and your own driving skill.

When you start with R compounds you don't have to go with the expensive and softest rubber tires. Lower cost and slightly more durable options are Kumho Victoracers and Avon Tech Ra. While they may last a full season they are not as quick but much better than street tires.

For a 15x7 rim you'll choose from:
205/50-15 a very good basic size, Kumho Victoracers and V710 come in this size along with the Avon Tech Ra and Hoosiers. Lighter in weight and cost with smaller outer tire diameter to help with lowered gearing for all pre-2005 MCS transmissions.
225/50-15 Kumho V710 comes in this size but for me they are too tall, might be an option for a 2005-2006 MCS with LSD.
225/45-15 which is my favorite. Hoosier A6 and Avon Tech Ra come in this size. The A6 is very expensive and short lasting for some drivers. I like the A6 much more than the Avon Tech Ra (better for track than autocross).

Suspension
I've run over one full season with stock shocks and H-sport springs on an MCS in SM class. And over one full season with Bilstein PSS9 adjustable coilovers. I'd say that both my street ride quality and autocross track ride quality are improved with the PSS9s but it's relatively expensive to upgrade and once you do add coilovers you also will need adjustable front and rear endlinks and you'll need to corner balance to get maximum benefit from the coil overs. You can get by without corner balancing but with ride height adjustability you can make balancing possible.

Stock shocks don't cut it. Koni shocks and lowering springs are OK. You can't adjust ride height and you can't fully adjust shock dampening. I didn't appreciate the very rough ride I had with the H-sport springs for daily driving.

Currently I set the front and rear coilovers to 4 and leave them there for both autocross and for street driving. There are 9 settings from 1 which is stiffest to 9 which is softest. 9 can be bouncy while 1 is very jarring. 4 to 7 are very usable.

If you are using stock suspension right now any upgrade in shocks or springs will be better than that. Having front adjustable camber plates and lower rear adjustable control arms allows for you to adjust front and rear camber. What is your alignment? It is also possible you have worn your shocks a bit. Using H-sport springs with stock shocks will tend to wear out the shocks in about one year with track or autocross use.

 

Thanks for the info and observations. Right now I'm running -2 with 1/8 toe out up front and -1.5, zero toe rear with stock struts and springs. My front bar is stock and the rear is H sport comp set to the middle pos (was full stiff with 17" S "lites". With this set up my 1st run is usually pretty lively but the tail settles down once the tires (Kumho MX) get warm. R compounds of some description are going to happen this year for sure.

thanks,

Russ

 

minihune – incredibly helpful post. Common questions so I know it can get tiring, but newer ppl (to the boards & to MINI autoxing) need it.

 

VT Mini,
What rims are you using?
You are using stock struts and springs still? Any plans to upgrade both?
Some ideas-
Front toe can be 1/16 to 1/8 out. If you feel you are ok on the street at 1/8" toe out then that is OK.
Front negative camber can be more if you like. -2 to -2.3 is OK whatever your own suspension parts will allow. More is usually better.
Rear toe can be 1/16" toe in to zero toe. Slight toe in is more stable.
Rear negative camber- while -1.5 is ok so would be less negative camber in relation to how much you have in the front. Roughly 1 degree difference in front and rear camber is a good place to start but it will depend on your suspension tuning and driving skill. -1.0 to -1.2 is possible.

R compounds will vary with your own needs. You will trade off price with longevity and traction. Higher prices usually mean more traction relatively and less longevity. For track use you want good wear and reasonable traction, something to tolerate the higher track temperatures. For autocross the runs are quick like 30 to 60 seconds so higher temperatures are less of a factor so less longevity is not as big a disadvantage. When you are starting out with R compound tires you will rarely make the best use of them until you can learn how to drive well on them and tune your suspension to make the best use of the contact patch you have.

 

Minihune,

Thanks again for the great info. I do still have the stock struts/springs but Koni yellows are on order so that end of it has been improved. I run 15x7 K1's and that made a huge improvement over the stock 17" set up. As you know, both the weight reduction and the better gearing offered with the K1's helped a lot. To further improve response I'm considering a UUC flywheel when I change out the clutch this spring. (opinions?) The car is not light (sunroof/stock seats) but it's more capable than I am at this point so sinking a ton of money into weight reduction is probably not the hot ticket for me now. Suspension, brakes, engine (with tons of seat time) is the correct order as I see it but I'd love to hear your opinion.

Thanks again!

 

After 30k miles on my 03, the ring gear on my flywheel self destructed. And several UUC owners have reported similar problems.

Although it's more expensive, for my '06 I'm considering the Exedy package of clutch and flywheel.

Not only is it almost indestructable, the package drops 26 lbs. (!) off of the OEM rig...