Well...........As choices are slim I am putting Works progressive Mr springs on
my 05 MR. We will see. I will be at Thunderhill Ca. with green-flag on 9/17. The
purpose is a street/track car. Coilovers are an easy solution for the track, but
a pain sometimes on the street. My car will be driven by me and an SCCA pro
driver(Speedvision world challange GT), who by the way is doing the work on the car. If the goals are not met then its probable Swift Mr linear springs! The car will
be on 225/45/17 Kumo's on stock wheels. Any constructive comments on progressive vs. linear springs on Evo Mr's for the track are appreciated. Additionally, I tried to buy a set of Ralliart springs(linear, 12mm drop) sold!
No Mas!

 

Personally if you are going to track, I will not go with progressive springs. You will lose some steering response and more initial body roll than a linear spring. Also during quick transitional (S-curve), you will feel the car is not that stable. However they are fine for the street.

 

Thanks for the response. I will post the results of thunderhill. Works told me
that they tested the springs on the track on an Mr. The results were
"much better handling than stock" (25mm rear sway bar). Having never used
progressive springs on the track, I am still sceptical. Thunderhill will be an
unbiased judge.
UPDATE!!.............Drove the car into the east foothills in Milpitas(Calaveras Rd.)
Car was "rock solid", NO push whatsoever. Transitions were very good. The
springs may be progressive; but come on very fast. The car now rides alot
like my 2005 Z51 Vette. You can now feel the road alot better but it hold its
line thru a turn better than the Vette on city streets. Vette tends to lose
front grip on irregular surfaces. So thunderhill next.(9/17).

 

Well...........Back from thunderhill. The car ran excellent. 2:15 by me and 2:05
by Al Becerra(SCCA Pro Driver-World challange GT). However, the limiting factor
was the springs! With max frt camber(-2 deg) we had excessive front sidewall
roll due to body roll. In spite of this the car DID NOT PUSH and was neutral
to the limit when rear wheel drift would take over. The springs seemed matched
to the car really well but not stiff enough to prevent excessive body roll at the limit
of the tires.(Kumos). So I guess it's coil-overs with springs in the 550lb range.