Kamran

I use the same technique, in the garage and at the track. In fact once a month after surgery on my right collarbone I could not use my right arm to lift. At the track I used my laps and left arm to lift and locate. But I get pretty tired at the end of day on track, changing tires back and forth before getting on the road heading home. I have also had studs messed up (not sure if it was my doing or dealer) where wheel must have been dropped on threads. I'm mostly worried about wheel drop/contact with stud threads.

X25

Some asked about my trailer setup. Here it is:

I use 4"-drop-axle, hinged fender, tilt, open trailer with high quality tires. This config does not get impacted by winds, and is lower weight than other solutions, too, so it's less drag on my truck.



The 4" drop axles get the bed much closer to the ground. This means much easier loading angles.


I bought aluminum trailer wheels from TireRack and upgraded to 6 lug axles (I custom ordered my trailer) for $90, which substantially increases the load rating of wheels, yet cuts the weight by a huge margin compared to steel wheels. I also use LT truck tires, which are good for 99 MPH, unlike ST tires, which are only good for 65 MPH. This way, I do have quite a bit of cushion if something goes wrong (having to speed to pass, lower tire pressures by mistake, etc.).


By only using tiny wood pieces, I can load any car.


I use a load-balancing hitch to make sure the load is evenly distributed.


This is how it looks. I use a RAM 1500 HEMI Laramie 4x4 Crew Cab w/ STD box.

BaylorCorvette

I really do not know what to attribute it to. I used a few sets on my ZL1 and they worked great, got maybe three weekends out of them. This time around on the Corvette only a weekend and a half which consisted of 3 HARD days, ~400-450 track miles. When I bought them for the Camaro and bought them for the Corvette I always had them heat cycled by the distributor. Maybe it was an anomaly and I got a bad batch. I'm not sure, but it left a bad taste in my mouth. Going forward I'm going to use scrubs but if I go back to a DOT tire I may try the R888R.

X25

I have a feeling that it was not a bad batch, but I'm not sure : ) 400-450 miles is quite a bit of track miles by the way, that might be it, too. On the Miata, they cord before they heat cycle out. Perhaps they just didn't get to cord before heat cycling out. I also wonder about your heat cycling process. Some of the methods might be overheating if not done right. If you will try again, try without heat cycling this time. I'd honestly never do heat cycling for entry level R compounds like NT01, unless it's Hoosiers, which I never tried.

Internetguru

I love your track build thread!

Todays economics of tracking a C7 are expensive and you have bravely headed in a scary direction down the rabbit hole and appear to have come out smelling like roses. Sorting out your own custom build. Well done.

I myself am headed in a more budget direction in order to focus on getting more track time before the CFO shuts me down. I am a novice that pretty much everything I hop in is going to contain more potential than I can currently unlock.

Many thanks for sharing the journey with us. One of my favorite threads as you brought us all along for the ride.

X25

Thanks for your kind words! It's been a journey indeed, and looks like I finally got some good results after a few bumps along the way! From here on, I'm hoping to keep changes subtle (in the process of switching fronts to Girodisc 2-piece for better cooling and weight loss, for instance), and will also try different suspension settings and tires, etc.

I'm glad to hear that the build thread was useful : )

Internetguru

As I prepare to jump ship from my C5 to a Miata track toy I need to study more. Do you have an NC Miata track build thread somewhere? Never mind I vaguely remembered you had posted a link, reading thru all 20 pages had my brain in a fog.

Went back to the first page and found you gave us a link. Reading thru another glorious X25 build thread now Many Thanks!

Maybe you can just sell me your Miata and build yourself a new one!

X25

Haha, yeah that would actually be nice since I like the act of building itself, but I presume you are looking for a bit cheaper build on the Miata : )

Miata.net forum has very annoying issues:
(1) It does not let you edit your posts after 1 hour or so. This means I cannot keep the first pages up-to-date on that build thread, or if I post a wrong information, I cannot add a disclaimer later on.
(2) For sale section does not let anyone else reply, and you cannot edit your posts, either. This means the for sale forum looks like a ghost town, and it shows your price history as well (all your discounts), making it a bit embarrassing, making it hard to sell anything expensive.

I've finally sorted out my 2.5 built engine on my Miata, and looking forward to try it out along with my race Öhlins!

Chets LS3

Are you going to L1 or L2 at spring mountain. I can provide some info for L2 if needed

X25

I am going to the L2 class (Jan 18/19 2017). I looked for good videos, but could not find any; they were all from lead-follow sessions : (

The only good lap I could find from the course was this one, but it says Level 3:

Then I looked up to see if there was a level 3 offered, but at least on the web site, it doesn't even mention it:
http://www.springmountainmotorsports...riving-schools

Any tips would be appreciated!!!

Chets LS3

That's instructor hot laps

I have some videos but I had some ad card issues.

First off don't get disappointed or think it's lead follow and you won't gain any Info from it.

Obviously there is a select few people on the forum who really go out and beat on these cars on the weekend. I was nervous it would be watered down and I wouldn't enjoy it. But I was going to Vegas the following three days so I figured it would be a good trip.

Day 1:
Lead follow. I was stuck in a slow group, I guess since I had no baseline and never attended the school. So first session was ugh. Second session I was put into the second fastest group. After that session I was with the three fastest z06s. All of day 1 was lead follow. But your following a pro driver. You might can give him a decent run but that's about it. I ran a 1:59 trying to catch an instructor. As he's talking with a Cb style mic.

Note; there's a lot of young really cool laid back instructors there with a boat load of experience. I picked their brain a lot and I'm sure you will too. JJ is a younger one who's well rounded imo great to talk too.

Second day you go into open passing with no instructor. Basically like a track day. You are split up into two groups. Slow group and fast group. You will be in a stingray which is good. You will be able to fight it out with the z06s! I loved that challenge.

As far as the PSS goes. Well there PSS's. And when your trying to go head to head with z07 cars. There not going to be too happy at the end of the session

I was able to implement some techniques at NOLA last weekend and I improved the TT2 record by over a second. I watched data overlay and was able to see some improvements that I took from the class. "Different ways to rotate the car" "brake balancing" and some other things.

I'm short you have a lot of skill on the track and I think you will have a great time and learn some stuff, even with your car modded heavily. Mine isn't as modded as yours but it's not too far off.

Ps. My videos don't have sound but when you go we can compare video and data. I think that will Be cool to do. Baylor too. Few different people from across the country at the same place. Compare driving styles etc.

X25

From the original discussion:
I always thought GS w/Z07 has the front spring rate of Z06 w/Z07, and that the chart above was just missing it, but I was mistaken. Indeed, GS only comes with 117 N/mm front springs, regardless of configuration. GM provides the required corner stiffness for GS w/Z07 with stiffer front sway bar, but the bar will obviously not work during heavy-braking. For more info on GS changes: GS: Z07 v. non-Z07 suspension & pkg questions.

Front spring rates comparison
Since rear rates are pretty similar between Z51 (FE3), GS, and Z06, I will focus on front rates:

• Z51 w/o MRC: 92.4 N/mm
• GS or GS w/Z07: 117 N/mm
• Z06 w/Z07: 190 N/mm
• My LG G2 @ 750 lbs/in: 177 N/mm (effective rate, explained below).

How I calculated the effective spring (not wheel) rate:
[Please correct me if you see something missing]
750 lbs/in is ~ 131.25 N/mm. However, coilover spring pushes the lower control arm from the shock mounts, while the OEM leaf spring pushes the control arm down from its housing location on the arm. The shock mount is about 13.5" away from the pivot point (the mount of the control arm to the frame), while the OEM springs push down about 10" away. As such, the effective rate for comparison is 131.25 * 13.5 / 10 = 177 N/mm.


The coilover springs push down from the shock mounts; 13.5" from the pivot of the moment arm.


OEM springs push down from the small housing reserved for it on the control arm, which is about 10" away from the pivot of the moment arm.


My remarks:

• My G2 coilovers seem to have the effective spring rate up close to Z06/Z07. Obviously, it will be even stiffer at the corners with my much-stiffer sway bars, but I also have 315s up front vs. 285s GM designed Z06 w/Z07 suspension for.
• GM engineers seem to be pretty much limited to what springs they have for coming up with GS (and even T1) setups. GM must have decided that 190 N/mm front spring of Z06 w/Z07 is too stiff for GS w/Z07 with its 100+ lbs lighter weight. That said, the 117 N/mm rate is obviously too soft. They remedied it with much stiffer front sway, but looks like GS w/Z07 could be an even better performer with stiffer front spring. I have also heard that GS w/Z07 also comes with same shocks as regular GS (in terms of valving), but with different tune. I am sure that different tune is also helping, but I have a feeling that they could do better with specific spring and shocks.
• As far as what I could experiment, FE3 spring rates are too low for wide tire setups. The amount of lean especially with 315/325 tires was simply eye-opening and tire-rubbing on all 4 corners! As such, it's mind boggling that GM decided to tune T1 race kit for these springs. I am sure T1 performs excellent for stock or near-stock tire sizes, like the 265s they use for the Michelin cup, but I would not go any wider than that.

EDIT: Reviewed my comments since front Z06 rate is 190, not 177 (oops!).

X25

Here's hoping it all works out well. The lead-follow format is just very confusing, since this is supposedly Level 2, and I don't see any other racing school doing that besides for the beginner classes.

Everyone seems to be happy, except the guy who said he worked on simulators, and that they made fun of him; we'll see : )

Kamran

Please double check the chart you posted.
Z06 w/Z07 fronts are 190. The rears are 177.

Thanks for the info and your thoughts.

I'm trying to have a better comprhension of GS base combination with with LG sways, DSC (assuming I can make some sense understanding the benefits) and scratching my head on the springs!

X25

Oops, right, will fix it now; thanks : )

If it were up to me, I'd probably install Z06/Z07 springs, shod the car with 18x11 / 19x13 wheels, and tune accordingly with DSC : )

Kamran

Kind of. Not quite sure yet. Z06 is heavier (front heavy), so spring balance may not be quite right. Haven't decided between GS Z07 and Z06 Z07 yet. I m going to go 18x11-13's on wheels. Almost bought a killer deal from a forum member, but he turned around and sold them from under me to a local buyer.

daleong

There used to be a level 3, but I think attendance really didn't make it cost viable for the school so they don't do it anymore. I think the options are to do level 2 again or schedule private instruction.

As Chet said, the first day is lead follow, but the instructors don't hold you up once you get into the fastest group. They are seriously quick and have thousands of laps there.

2nd day first session is lead follow if I recall and the students get turns to lead... the instructor is the follow, with the rest of the group behind.

The instructors will ride with you also.. can't remember if it is the first afternoon or second morning. End of the first day you ride with the instructors - they beat the crap out of those cars.

I was in the class with the guy who did the simulators - he made a bigger deal out of it than it was. He was very fast anyway - but cost me some track time when he went off at the first turn into the gravel.

It was cold (40-45F) and I was running 2:03's in the 2nd fastest group. The fastest guys were in the 2:00-01 range and I think the fastest lap was a high 1:59 - there were some guys with lots of track experience in that group (including simulator guy). Instructors were doing 1:57's if I remember right.

BaylorCorvette

Yeah I'm not too worried about the pace, lol. Maybe I'll be in the slow group and X will be in the super fast group.

X25

Hey hey, I'm not suggesting I should be in a different group; I am merely suggesting that this lead-follow format is likely not the best way for me to learn : )

If they force me to stay in 3rd or 4th gear only, for instance, I might get black-flagged : P

Kamran

There's also the super-duper fast group, for all you drag racer kind!

But really, lead follow is a very quick way of learning a new track's fast lines, if you've never been to it before, and as long as you are free after a few sessions to do your own exploring test and try! As long as the leader actually does show you the fast lines. The drawback is sometimes they don't and only show you the reliable lines!

When I go to a new track, I wouldn't mind following a fast guy to learn the track. That or having traffic (as long as passing is allowed) so you can see where the track is a few turns ahead of you.