Coil over spring rates

[Topless]

Originally Posted by Hasbro

Good Stuff. Wish we had a like button. Topless, thstone, either of you run a square setup? Aren't the PSS9s going the way of the Dodo bird?

Yes PSS9s are now being replaced by more advanced struts like JRZ, Moton, and others. A timely thread as my Cayman has 70k miles, of which maybe 20k on race tracks and the struts are pretty far gone. Having discussions now with my setup shop to determine the best dual-purpose struts and springs for my weekend joyride/track steed.

RE: Running square- I ran both ways and gathered a lot of comparison data. For tight tracks and AX I found 255/255 to be a bit quicker but longer tracks with higher speeds favored 225/255 for the fastest laps. They were very close but the trends were clear. In wheel to wheel racing there are advantages to having more grip in the front for quick moves and going deeper in the braking zones. I think most BSR drivers run 255/255 for this reason, as well as the ability to rotate all 4 corners for best tire management.

Others may have different experiences with tire choice but this is what I found over 10 years with my 986.

[rastta]

Originally Posted by Topless

Yes PSS9s are now being replaced by more advanced struts like JRZ, Moton, and others. A timely thread as my Cayman has 70k miles, of which maybe 20k on race tracks and the struts are pretty far gone. Having discussions now with my setup shop to determine the best dual-purpose struts and springs for my weekend joyride/track steed.

RE: Running square- I ran both ways and gathered a lot of comparison data. For tight tracks and AX I found 255/255 to be a bit quicker but longer tracks with higher speeds favored 225/255 for the fastest laps. They were very close but the trends were clear. In wheel to wheel racing there are advantages to having more grip in the front for quick moves and going deeper in the braking zones. I think most BSR drivers run 255/255 for this reason, as well as the ability to rotate all 4 corners for best tire management.

Others may have different experiences with tire choice but this is what I found over 10 years with my 986.

The Ohlins RT's I put on my Cayman are THE best street coilovers I've ever used. While not on my Cayman, I've owned KW V2's and V3's, Penske's, Bilsteins and others and the Ohlins are far superior on the street. I'll stick with my 2Way Motons on the track.

[steved0x]

Originally Posted by rastta

The Ohlins RT's I put on my Cayman are THE best street coilovers I've ever used. While not on my Cayman, I've owned KW V2's and V3's, Penske's, Bilsteins and others and the Ohlins are far superior on the street. I'll stick with my 2Way Motons on the track.

I've got the Ohlins on my Cayman and have about 10,000 miles on them and maybe 9 HPDE events, I love them and so has everyone that has ridden with me. I've never experienced any "higher spec track only" coilovers but for a dual.purpose hpde/weekend cruiser, I think they are great. When they wear out, and if I start trailering the car, I'll get them upgraded to a track only spec.

[Hasbro]

Thanks, looks like Ohlins is the way to go for me. I also spoke with Ohlins in North Carolina and they convinced me not to drop the spring rate and that I will be very happy with the 400/457 springs. Brian at Ohlins said to go as far as a 15 to 20 mm drop, possibly more but to be careful as there can be rear axle contact. That will be plenty and gives me maneuverability with my initial tires, which will also drop the chassis 1/2". I'm thinking initially to try a safe 100mm chassis to ground setting plus -13mm from the tires. About ready to start a build thread.

[Topless]

Originally Posted by rastta

The Ohlins RT's I put on my Cayman are THE best street coilovers I've ever used. While not on my Cayman, I've owned KW V2's and V3's, Penske's, Bilsteins and others and the Ohlins are far superior on the street. I'll stick with my 2Way Motons on the track.

I appreciate the tip on Ohlin RTs Rastta. I was pretty disappointed with PSS9 on my Boxster and wanted to steer clear of Bilstein but JRZ is just too precious $$ for my planned use. At $2900/set this is a reasonable coilover with good reviews for dual sport use. My other option is a Cayman R "kit" for $2400. I have enough laps in cars with these to know they are pretty good street and track but the RT adds ride height adjustability. A worthy contender.