I thought about it for a while before posting this and to which forum. In the end I decided I could probably help someone else with a new GT3 who may very well end up in a situation similar to this. I expect the usual flamethrowers to do their thing, I might deserve some of it, not sure in hindsight. I have 23 track days (this was event #6 this year) so far in 24 months, six tracks, three different cars, four depending on how you look at a heavily modded car. I run in Int 2 with SCDA, Red with Audi and White with PCA. I have not spun or been off track before and short of a few interesting oversteer/understeer lessons along the way have steadily advanced and felt very capable in each new car and scenario. I have had perhaps more instruction than some because I have run in three clubs and moved up three levels in each after 16 months requiring various instructors to get that far.

I ran my new to me '04 GT3 totally stock at Lime Rock and Watkins Glen for three days total before changing it. Then I had the toe links done, the usual track alignment, lowering and corner balance and the shocks revalved, new springs (a Dan Jacobs suspension), moved to MPSC tires and Volk TE-37's, Pagid 19/14's and a roll bar. I took it to NHIS knowing the car would be very different. It was the first run at that track of the year, the first in a GT3 and the first with it tweaked. I knew I was in for an interesting day.

Session one was a huge learning curve evaluating all the changes and getting comfortable with the line again. The tires came up 9 psi from 26f/29r to 35f/38r, surprise #1. Session #2 tire pressures were dropped to 32.5f/35r, the most I was willing to change in one outing. On that first lap I told myself that I would go out "easy" and build the tire pressure back up. After almost a full lap into the NHIS turn 11 I spun it, a one-eighty actually. Turn 11 is the main left turn in a series of twists on what is the inside track of NASCAR's turn 3 and 4.

I lot of things happened here to make this spin occur and thinking I was aware of them all did not make a difference. Because I went out slower (the plan) my entry to the turn was in effect easier and I got the car not just to the apex but both left sides on the curb somewhat. I had been there before in two other cars and even had the GT3 (unmodded) on a few apex curbs this year slightly with no issues. This time the car spun in what I can only describe as instantly as the back tire came off the curb. The car spun 180 out and proceeded to basically back toward the media building and barrier that is just before pit entrance and the front straight. It stopped one inch too far, the flexible right rear fender getting a three inch scape from the armco and no other damage besides my ego. Could have been much worse. Why is the focus here though and how to avoid doing it again for me and maybe ever for those of you who may be contemplating these mods or at a similar experience level.

My read so far on this is the tires were still cold and the new suspension does not tolerate curbs on turns anywhere close to what it did before. Where I have had oversteer enough times to feel very capable correcting this time it was over before I knew it. My initial correction was useless really, it was going around, as the spin progressed beyond probably 45 degrees in a split second it was clutched and full brakes.

If you are going to do suspension mods to your car in what now appears to be obvious to me I can tell you she may not like the curbs much at all, not that I ever really planned to use them much but was happier just getting on them vs missing the apex. MPSC's not to full temp don't help either after hopping an apex curb while squeazing on throttle but I say again- I had done this before just in a different car. I thought I was going easy and I was expecting the same result as in the past but did not get it this time. The rest of session #2 was spent with some confidence rebuilding as I felt it out more.

Sessions #3 and #4 were fantastic after dropping pressures a second time to 32f/34.5r. The Dan Jacobs ride was very nice, the Pagids and MPSC rubber excellent. I have a newfound healthy respect for the apex curbs and will be more aware of how and when I use them. I regard this as something similar to lessons learned in many years of aviation in a variety of aircraft from Cessnas to the F-14. Until you depart the normal envelope, a spin qualifies here (!) you actually do not know where the edge is. I know where it is now in this car and with these mods and that particulat type of corner. I will see that scenario again and be wiser. I got off easy. I want to save someone else who finds the edge from an ugly outcome. Pick your corner to feel out any mod's, cetainly ones like I've done so you don't do what I did.

This is my substitution for writing "don't do this again you moron" on the blackboard one thousand times

 

Mistakes do sometimes happen and if you have been tracking long enough you are bound to have spun (or had a 2 or 4 off incident) at some point on the track. Just be glad that you have learned from it and did not badly damage your car.

I wouldn't worry too much about the "any spin is an abomination" folks.

 

It's not possible to anticipate every scenario...

 

This sort of thing happens. If you push yourself and the car something unexpected is bound to occur eventually. So what you scratched the bumper, its not like you really did some damage. You learned something right?

Have fun thats what its about.

 

The great thing is you know what you did and you learned form it. My only suggestions is to ditch the MPSC and move to a better tire for the car. The Hoosier R6 is a better tire and more predictable unlike the break loose for no reason MPSC. Right now I am running the NT01's and then going to the R6. The NT01 is a great tire but a sec or two slower than the R6. However, it TALKS to you and is VERY EASY to control through TB'ing and throttle steering.

 

Interesting tyre pressures.... In the UK we tend to run 30/31 hot all round with the cups. Might be worth trying.

 

30/31 is too low for the cups. you should be in the 32 range up front and near 36 in rear. Camber is essential for the finicky cups to work best.

 

Regarding the Hossier's Dell, they don't make a front in our exact size. Which one are you planning on running? I have been happy with the MPSC's so far, they are temp sensitive clearly.

As to the tire pressures, yes, I was not looking to run them so high either. The day started cool and I figured I get less than 7 psi increase into them session #1, thus my starting pressures.

Knowing they are temp sensitive and having no one to measure that on a hot lap I'm going off of pressure immediately following a session as are most guys. I have understood 32f/34r was generally the sweet spot but with more on this car in the rear because of the weight and it's performance capability. It does appear that he wear of the tire supports a 32-33 front and 34-35 rear to not get into the shoulder much. I would be afraid to go out looking for 30/31 hot, the starting temps would have to be 21f/22r and roll off would be an issue I think.

My camber is 2.5 front and 2.0 rear.

 

I was at NHIS on Monday with my 2005 gt3 with mpsII and my new cup links... I wonder if you were to far inside on that turn? We ran the silly motorcyle course as the normal road corse was closed. But I never was tight to the left side on that apex. I was hard braking about 5 feet off the inside and then making the turn.. This may just because we ran a different configuration.. (I had a small spin on my last run on the right hander going up the hill after I had a very hot set of street tires. Thankfully, no issues.) I need to get new tires too, but think the PSIIs are going back on .. Tim

 

Only time I spun my GT3 was the first time out with it. Fortunately, no damage. Lesson learned.

I run the MPSC's 32F & 35R hot and they work great, but you need to let them warm up before you get aggressive. My camber is -2.5F & -2.25R. It's a good combination.

 

Roscoe, saw you there earlier and wanted to talk rotors with you (mine are steel and cracking) but never saw your car again after the morning tech and first run. We must have been in different groups. That configuration is all I've ever seen at NHIS. I was alway taught to get in tight to the apex to get a good exit for the straight. Obviously I was too tight that one time. Wish I could have followed you to see what line you use there. It seems a bit far off the apex but hey, my line had more surprises

The righthander uphill you speak of is initiated with turn three (and then four?) and a very interesting corner. I was following a paddle shifting Ferarri 430 session one for a while and when I took the turn in third I would lose ground on the uphill at full throttle but have no tire spin. Trying downshifting to 2nd into three is a busy evolution but when I did that I could stay with the 430. Point being here is that I was faster. The problem was the entire turn and uphill was an oversteer nighmare waiting to happen. The back tires could/would break free easily and with the pavement transition there it was hard to modulate it perfectly. Sounds like that's where you spun. Were you in 2nd or third doing that corner and uphill? I can see it happening in either gear but 2nd would be easier hence my concern.

Scott, fun video, love the technology. I wish I had it to review my spin.

Holger, I hear you on the tires warming up and undoubtably that was an issue. It's also one of the interesting parts of my spin lap. Because it was lap one of the second session and I was actually going slower to do exactly that- a tire warm up, I was able to really turn the car in easier to the apex. I believe overdoing that and getting on the apex curb is what did it for me and probably the still warming tires had enough reduced grip to contribute. So, in effect, trying to be cautious put me in a speed range where I could turn more, overdid that and the combination of a less tolerable suspension to curb hopping and the tire temps resulted in a snap 180.

My rear camber is -2.0, do you think -2.5 would correct some of the oversteer this car is happy to exibit? Seems like it would. Do you run the rears -2.5 for that, tire wear or both?

 

I dont think we ran the same day...I was Monday (Mem Day) with SCCA... I think you must have been with Ian and SCDA...

 

Oh, got it now. "That" Monday. Yup, I was there Tuesday, SCDA. Funny, there was a white GT3 there too but it disappeared.

So did you run the uphill in 2nd or 3rd?

 

I have use both 2nd and 3rd... I think 2nd is to risky in terms of kicking loose the rear end.. I have had other track sessions where I was doing the uphill in second and had to correct sharply for oversteer (rear end up hill first!). So this day, I stayed in third.. Good thing is our motors have plenty of torque to pulll us thru.

 

Driving is all about seat time
In the big picture you really don't have all that much.
Curbs will unsettle a car....