Just got back from Buttonwillow last Monday (16th) with CFRA. Day was overcast and sprinkled on and off all day. Isn't this May? We ran configuration #1

Suspension is DMS 50mm with 650 front and 700 rear springs. 25mm rear swaybar on full stiff. It's a bulletproof design and takes curbing very well. The double progressive springs are nice on the street, but allow a lot of suspenison travel before taking a set, even with the stiff springs, which is my biggest gripe. 700lbs is a high as they go, so not much to be done there. These might just be sold for that reason. The shocks are 4 way adjustable in rebound and 16 in bump. Camber is set by using a combination of DMS's concentric washers on the upper bolt and the camber plates. If's anybody's interested let me know...

Overall the day went well. I qualified on pole, but had a really bad start letting a corvette by on the start. Starter kept telling us to slow down as we approached the starter stand and wouldn't throw the flag. Finnally I just touched the brakes to scrub speed, and wouldn't you know, he through the green flag. (Ugg) Spent the next 10 laps chasing the vette. He had more brakes, but was breaking earlier than me. That makes it really hard to close in without giving the car in front of you a tap, and touching is severly penalized. The corvette and EVO are an even match in speed (Buschur stage III) so we had a lot of fun dicing. Only place I had any chance was star mazda under breaking, and I just didn't have enough to get him. Finished second, but took fastest lap of the race with a 2:06.

Bill

 

Nice work! Did you change you alignment yet? (20 in bump too) what were your settings bump VS rebound?

 

bump is set at 3 front and rear. Rebound was full stiff at rear and 5 clicks softer in front. Alignment was not changed, although it is needed. alignment is as follows:

Front 1/8" toe out
-2.5 camber due to clearance issues that need to be resolved
Rear 1/8" toe in
-.7 camber


Ideal would be
Front 1/8" toe out
-3.5 camber
Rear 0" toe in
-.5 camber

Even with this I think the car is going to push. It was a plow. Probably at least 1.5 seconds once I get the car balanced.
Toasted a set of front Victoracers in one day at the track! They were new at the start and corded the outer edge on the left front at the end of the day. I've got to get the camber thing worked out.

DMS_Mark - Make stiffer spings Please!!!!

 

What wheels are you running? offset etc.
Tire pressures hot?

 

I bet your front tire pressures got pretty high, right?

I got -3 degrees upfront and my car does not push like you explain. Although if I remember correctly I have less toe-out than you do. I could always use a little more negative camber and toe-out but I drive my car on the street too, so I have to compromise.

Personally I like the way the DMS progressive springs work, to me they are very predictable and controllable at the limit.

n

 

Nils,

I agree the DMS has been easy to drive. I have no complaints with them from a performance standpoint other than them being too soft. The push is a function of setup and can be dialed out. I just ran out of time seting up the car. Work keeps getting in the way of racing! Front toe out will help with understeer as will less rear toe in.

I'm running the 275/40/17 Victoracers on 17x9 ET35 at 30psi hot, and checked them after every run. As another data point I shoot for 40psi hot on the Toyo's. I've talked to Kumho about the Victoracers and they like the low pressures. They recommend running them until the tread/sidewalll junction starts heating up. The fronts did gain a lot of pressure from cold.

Alignment and softening up the front will cure the understeer.

 

btw - good job at the race!

 

Hey Guys,
Just a note to correct some "spec info here"
Rebound is not soft/hard it is slow fast. The stiffer the bump setting (closer to 0 - full clockwise), the slower the rebound you want (position 3 is the slowest, 0 is the fastest) to allow the weight to stay transfered and avoid an "OVER SPRUNG" setup.

Bump is hard / soft. Position 0 is full hard (full clockwise) and position 20 is full soft. (2.5 rotations = 20 clicks counter clockwise)

Rock on guys,
mark

 

great job bracer!

 

Pictures

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