M030 Setup with Lowering Springs

[truegearhead]

I've been competing in SCCA B Street for a couple years now, and would love to slid down the slippery modification slope a little further. Looking at the Solo events board announcement in May it sounds like Boxsters might be allowed into STU next year. Street is probably the most competitve spot for me since I'm not going to dump a bunch of cash to prepare the car but I'm still considering it. My biggest concern is suspension. Last year I installed the M030 suspension with a GT3 front bar, I'd hate to rip all that out. If I kept the M030 setup and installed lowering springs and camber plates do you think I would have a workable setup? At first glance the 20% stiffer M030 shocks seem to match the increased stiffness of most after market lowering springs




For those of you interested here's the announcement

SOLO EVENTS BOARD SOLO EVENTS BOARD | May 27, 2015 The Solo Events Board met by conference call May 27th. Attending were SEB members Steve Hudson, Dave Hardy, Mark Andy, Mike Simanyi, Richard Holden, Brian Conners, Eric Hyman; Doug Gill of the National Staff; Terry Hanushek of the BOD. These minutes are presented in topical order rather than the order discussed. Unless noted otherwise the effective date for all new rule, class, and listing change proposals herein is 1/1/2016. Comments regarding items published herein should be directed via the website www.soloeventsboard.com
......

The STAC is considering allowing some mid-engined cars, such as the Porsche Boxster, into STU. Per the above proposal, these cars would be limited to the same tire size as AWD cars. After collecting data to review the performance potential of ST mid-engined cars, allowances could be adjusted, and/or the cars could be moved if appropriate. Note: The STAC and SEB believe the new wheel restriction will improve parity between cars that have more room for extra-wide wheels and those that do not. This also directly addresses cost escalation issues that have been expressed as a barrier to entry. The STAC has queried many STU competitors and found none running wheels wider than 11” so this proposal should hopefully not be a takeback.

http://cdn.growassets.net/user_files/scca/downloads/000/007/720/15-fastrack-July-solo.pdf?1434725488

[Topless]

A couple questions.

What tires will you be running?

Do you have ROW M030 suspension now?

Adding the ROW springs will lower the car a bit and maintain proper rake and geometry. A lot of aftermarket lowering springs get the car too low and goof up the geometry causing it to have less grip and run slower laps. Not ideal for competitive SCCA AX.

[EJ-Fresno]

Will a US M030 lower the car as well? Or only the ROW does?
Thanks.

[Topless]

Originally Posted by EJ-Fresno

Will a US M030 lower the car as well? Or only the ROW does?
Thanks.

Only ROW springs.

[EJ-Fresno]

Thanks for the answer

[truegearhead]

Originally Posted by Topless

A couple questions.

What tires will you be running?

Do you have ROW M030 suspension now?

Adding the ROW springs will lower the car a bit and maintain proper rake and geometry. A lot of aftermarket lowering springs get the car too low and goof up the geometry causing it to have less grip and run slower laps. Not ideal for competitive SCCA AX.

I'm running rs3 2s this year. I'll switch to the re111s as soon as I can though. I'm also running the euro m030 springs shocks and rear sway. How much do you have to do to fix the geometry?

[edc]

You will probably need some rear adjustable toe links and to extend the top mount slot for extra front neg camber.

[woodsman]

I THINK Topless is referring to the camber and toe curves being negatively affected by the LC arms being north of parallel once lowered deep enough. To remedy that you have to alter the pivot points of the arms.

[Topless]

Originally Posted by truegearhead

I'm running rs3 2s this year. I'll switch to the re111s as soon as I can though. I'm also running the euro m030 springs shocks and rear sway. How much do you have to do to fix the geometry?

My recommendation is to stay with M030 ROW springs. No advantage to getting the car lower and Porsche engineers got the math right. If you were running Hoosier A7s or Avon Slicks I would recommend more advanced struts like JRZ or Moton and a lot higher spring rate with a pro corner balance and setup. On street tires there is no benefit.

[The Radium King]

Originally Posted by edc

You will probably need some rear adjustable toe links and to extend the top mount slot for extra front neg camber.

+1. you're good with suspension improvements unless you want to go full coilover and adjustable rear bar. put your energy into alignment and any parts needed to acheive that - rear links, front control arms (or camber plates, or slot your front strut towers) and front tie rods if you can't get the toe in spec.