997gt3north

I have decided to give PASM re-valve a try to see if I can subtly change the car's dynamics without going $$$ crazy and buying a real suspension.

The car's as delivered spring rates are:
Front 40 N/mm - 228 pounds / foot
Rear 105 N/mm - 600 pounds / foot

The mk2 uses
Front 49 N/mm
Rear 115 N/mm

The spring I am going to be using is
Eibach 250-60-0080

This translates to
250 - 250mm (stock is 233mm) so a tiny bit longer
60 - 60mm (this is the stock Internal Spring Diameter)
0080- 80N/mm (457 foot pounds for translation)

My goal is to firm up the front of the car but to keep it as streetable as possible. This will give the car a 450/600 setup - if I want, I can install the rear mk2 spring to bring the car to 450-650 but a 50# increase isn't worth the hassle in my opinion. If I decide later, that I want a KW Clubsport type spring rate setup, I will send the Rears out to be re-valved for 900#s and then figure out the machining for the rears (the TPC Racing solution).

I sent the shocks out today to Bilstein in California - addressed to Ryan - only to find out that I think Ryan is gone as of today - I think Wes is the new Ryan.

I am going to have a detailed conversation with the person doing the re-valving to see what is possible, but I think I will just have them scale the stock compression / rebound profile to work with my 450# front spring choice.

I have also decided to try some rear RSS suspension pieces to see how they 'feel'. RSS (thank you Alex at Sharkwerks), is selling a new 2pc Rear Lower Control Arm at comes with a mono ball and a solid caster puck - this allows me to avoid the labor to push out the stock pieces - and I get to keep my stock LCA in stock condition. I will also be installing the RSS Rear Upper Control Arms (dog bones).

I will post updates when I get the car back together.

Terry L

Paul - see if they will tell you their specs for the B-16 Damptronics. That takes you from 225 lbs to around 350 in the fronts, and I think only to around 650 in the rears. They valve the shocks to match, and it is nothing more (or less) than a PSS 10 with a two way switch instead of a **** with lots of positions.

mooty

kill off the pasm and put jrz or moton on.

Izzone

If I forgot to tell you

Thanks for the walkthrough at mosport

It is my favorite track of manication.....and over Sebring

You are blessed to have it in your back yard

Crazy Canuck

+1

NJ-GT

why use heavy and long springs when there are more efficient options with the stock shocks?

tcsracing1

Throw on a set of Damptronics and call it a day.

mdrums

If it wa me and I wanted to keep the PASM normal and sport mode I would just put on the Damptronics. Or if I did not care about PASM settings I would go to something like JRZ - Moton - Ohlins or Penske.

Go with a set up that has been tested, figured out and proven unless you are just tinkering and have the cash to blow on re-valves and a bunch of springs to try out.

TPC Racing

We just picked up a new RS for doing more of this work... Our cup car has been working really well recently due to some changes that mike is doing to the Chassis. If there is interest here I will certainly post more of our findings.

sharkster

This is great news mate... keep me posted

Bman

I guess so...Mike's got the pole tomorrow at Mosport!!!! Congrats!

997gt3north

Mini Update:

I will be going with a Swift spring as it was available.

The Swift Spring specs
Part Number Z60-228-080
228 is spring length in mm - stock is 223, so almost perfect for minimal adjustment
080 is for 80N/mm or approx 450# spring

Terry L

In retrospect, I think the B-16 Damptronic is a compromise which didn't work. It is still OK on the street and the car definitely turns in better than it did before, but it is still too soft in the soft position. On the other hand, the stiff position is really unusable except maybe if the track is made of glass and it really makes the car nervous. I am 2 seconds a lap faster around the Glen in soft rather than stiff. I'm no expert but it seems like the springs and the shocks don't work together on the stiff setting. I drove a friend's GT3 with Motons and heavier springs and, although I was hesitant to push the envelope, the car seemed more comfortable and also better planted and less nervous. I am curious about the TPC solution but it is awfully pricey to keep your old shocks and get an electronic massage, even though it is Mike's secret sauce. I'm curious to see how your experiment works out.

tcsracing1

What were you running for tires on the B16 Damptronics and at what ride height?

Terry L

The tires were Goodrich R1s. The ride height is as specced by Bilstein, slightly lower than stock - maybe 10 mm?