kfmcmahon

Anybody own a DSC V2 going to WGI this summer and willing to let me swap out for 1-2 sessions for my OEM so you won't miss any track time? Dinner and drinks on me after the track goes cold

Also, for those who do own it, do you feel it is worth the price?

Car was moving around a ton under threshold braking (front and rear!) going into turn 17 at PittRace last weekend and also noticed this a bit at WGI last week. And finally does anyone own just one with two separate software downloads for GT3/4 and swap between GT3 and GT4 for track ?

thanks, Kevin

jmartpr

Hi Kevin...I have the DSC V2 with the latest map from TPC + their rear toe links. The improvement is noticeable, specially on the case you mention. DSC even compensates for weight transfer during hard braking. IMO I think is worth the price and if the car is dual purpose it's even better during normal driving.

Bill Lehman

Stability under hard braking has been an issue with the GT4 since they were first tracked. The original solution was to increase rear toe to about 3mm per side. I did it and it works. I've asked other drivers about the DSC unit and never received an affirmative answer.

MarcD147

+10 to what bill said

Also make sure you steering is perfectly straight when braking hard.

When doing video review of my data with David Murray and he noticed I wasn't straight.... I thought I was.
It explained intermittent stability issues into T1 at VIR

jmartpr

The best solution so far for this issue is a good alignment with rear toe spec as you mentioned. I would say the second best thing you could do is the TPC rear toe links followed by the DSC. The DSC alone does improve stability due to less weight transfer during hard braking so you get much less toe change, but still you need the rear toe adjustment. Hopefully Tom Chan from TPC will chime in and provide all the technical side and how it works.

kfmcmahon

yes, I have the TPC rear toe links and the toe specs for the rear are per TPC, as my alignment guy talked to them extensively about alignment set up for a 50/50 street/track car

toe in is 15 each side so 30 total
front is zero toe
camber is -2.5f with tarrett race plates
camber is -2.0r with tpc toe links

felt great everywhere but 17 pittrace (135mph down to 45) and turn 1 at the Glen (135 down to 80)

maybe set PASM to soft/street setting and see if that settles the back down? Rear sway stiff. Front soft.
really disconcerting part was the FRONT was unstable at Pitt😳

jmartpr

Your setup is a is exactly as mine, maybe I have a bit less toe on the rear (don't remember from last alignment). Our speeds are not that high, we go from 110-115 MPH to 30 MPH at the end of the main straight for a left, 180 deg turn. Stock car you could feel the rear moving during the braking. For the next event I jumped all in with the alignment, toe links and DSC and the difference was day and night.


Besides helping with the weight transfer/nose dive the DSC also improves the rebound/compression with a specific MAP for the TPC toe links.....Tom Chan from TPC sent me a MAP that works together with the TPC links and improves the unsettling of the rear during braking. Tested the new setup about 3 weeks ago...not sure if I was faster but the car is easier to drive.


I think it also comes down to your driving style and getting used to the characteristics of the car.

aryork

I had same experience. Instructor with a GT4 indicated not being exactly straight would induce back-end wobble during hard braking. I experimented a bit and it seemed he was right. Maybe the better toe links will allow stable braking even if you are not exactly straight. That would be nice...

Tom@TPC Racing

Here's one driver with an answer
https://rennlist.com/forums/gt4/946770-dsc-box.html

I have driven many cars with DSC and it does noticeably improves stability. It is a hot product and it works. Due to favorable word of mouth reviews GT4 DSC has been sold out since May. Should have them back in stock in a week.

kfmcmahon

yes Tom, I have read that thread in the past
Mark and Rick at Eksten's in Rochester set the car up for me 2 weeks ago...

kfmcmahon

can you get different suspension "tunes" for different tracks

Can you also swap between a GT3 and GT4 depending which I am taking to the track?

Tom@TPC Racing

DSC users can make adjustments to the maps that we provide should the user want specific characteristic for personal preference. Adjustments to the map can be made and saved as files using DSC software. But usually map tuning is not done for different track since DSC is not a passive system. DSC is fully dynamic/active in that the damping values are adjusted to the amount of load while you are driving. The load includes g-force level, the direction of g-force, rate of change of g-force, driver input in braking and throttle, and suspension travel velocity. Each corner of each track and even surface conditions at the time has a particular "load signature". DSC adjusts to the driving load signature using our proprietary algorithm. Revolutionary stuff. Being a DSC user personally, I took me about a year to separate my suspension tuning thinking for the traditional passive thinking that I have done most of professional career prior to this technology.


Yes. 991.1 GT3 and 981.1 GT4 take the same DSC.

kfmcmahon

so, I bit the bullet and got the DSC V2 for both my GT3 and GT4 with TPC rear toe links.
new PB by 3 seconds in the GT3...consistently lapped 2:04's on Trofeo R's and one (gasp) 2:02.66 flying lap before I ran out of gas (literally fuel pump starvation and limp mode on the next lap!!--almost needed a tow)

back at WGI this Monday, with the GT4 so I will compare PB's for that to see if this is legit or not..it is a lot easier to remove/replace in the GT4 compared to the GT3 with non-folding LWB's, so I may swap after each session for a real apples-to-apples comparison

PCarOMFS

Very impressive Kevin. My Dad and I are planning go to TPC over the winter for alignment and DSC in our cars. I think your set up is ideal for my GT4. We're heading to the Glen Friday and Saturday. Can't wait!

kfmcmahon

yes, I saw your names on the roster for the Metro NY event....I wanted to do that one, but unfortunately have to take my daughter to college in DC

I am at the Glen monday with Audi club so will bring the GT4 with the DSC installed