Mjolitor 68

Recently Homestead has opened up NASCAR turn 3 & 4 for us and I'm in love with the bowl. My front straight speed has gone up 25 mph from the previous track layout and thats on old tires

So my question regards the forces at play on a car in the banking, specifically I am concerned about doing the banking over and over on stock uprights. Obviously a stock Z is not built for running on high banks

Because of the aerodynamic aids I added to my Z right in the middle of the banking I feel the car squish down on the road that tells me she wants max power now and we rocket out of the corner at 135 mph

Its tons of fun but can the stock uprights handle this abuse ? Any other suspension bits that should also be upgraded ?

Thanks

69427

Just a thought, but it's my guess that your suspension would see higher forces and stress from hitting a decent size pothole on occasion than what you're going to put onto the suspension running some banked tracks.

Just my thoughts. YMMV

rfn026

The hardest part about banking is learning to looking out the side window when you're on the banks.

Richard Newton

saibel

I just got back from running Texas Motor Speedway. We ran turns 3 and 4, the front stretch, down onto the apron, then through the road course and back to 3 and 4. We asked them why the did not allow us to run 1 and 2 at speed. The instructor told us that the load on the right front tire coming into turn 1 at 145-160 would be too much for a street car to handle. Hence putting in cones that make you shed speed.

Mjolitor 68

I noticed my passenger side brake pad wore a lot faster than other side

I was braking from 150 turning back into the infield

JimbeauZ06

I'll be running in a DE on the 24hr course at Daytona in October during PCA's Club Race. Last year a GT3 blew the right front coming out of Nascar 4, spun down toward the apron, overcorrected and shot up into the wall. No one was hurt but the car was wadded up like a ball of foil. Some of the pros made comments about the tires he was running (Hoosiers) not being the best choice and possibly contributing to the crash.

Just curious as to anyone's thoughts on having fun while avoiding this scenario. I was not planning on changing my alignment set up (T1 setup by Phoenix for road course) and have a brand new set of Nitto 555 RII set aside for the event.

BTW the GT3 driver had HPDE insurance which sounds like a pretty good idea for this event.

TLGunman

The Mosler MT900R that won the GTS class at the 24 Hours of Daytona in 2003 was running stock C5 uprights. They didn't have any issues with the high banks there, Homestead, or Fontana.

AU N EGL

My major concerns about high banking is oil starvation, and the wheel camber.

Left hand sweepers are on of the causes of oil starvation and blown engines. and what is a banked NASCAR track? Left hand sweepers.
This is were a dry sump or atleast an accu-sump helps

Too much camber on the banks makes handing very very hard.

When you look at the NASCAR cars they almost have Positive camber in the right side. and almost no camber on the left.

I dont think it was Hoosiers, but tires without inner liners. or tires that have softer sidewalls.

Events on bank tracks can be fun, but also can be harder on equipment and more dangerous.

BEZ06

Same thing at Daytona - they have a chicane (the Bus Stop) on the SuperStretch (the back straight between NASCAR 2 and 3).

Here's a cockpit view while on the 31 degree banking just about to come out of NASCAR 4:




Like Richard said, you don't look out the front of the windshield - I find I need to look up in the left top corner. It's very comfortable after a couple laps.

I think the hardest thing is SA on cars behind you. Unless you have a spotter talking to you on the radio, you don't know who's behind you. You can't see anything in any of rearview mirrors except the track right behind you. You could set up your right side mirror to look up and right so maybe you could see somebody back there waiting for a point-by.

At the 3 HPDEs I've been to at Daytona, all passing on the banking was done to the right - the slower cars need to stay low, and they need to be aware of somebody on their tail coming out of the infield or the chicane, stay low, and just give a point-by.

There is quite a bit of downforce on the car generated by the banking. In the picture above you can see a friction circle to the left of the tach, and between that and the tach is a numerical readout of G forces. The resolution is kinda lousy, but I think it says 0.8 and it's all a lateral G to the right.

There is also quite a bit of additional positive G (downforce in line with the vertical axis of the car, and perpendicular to the surface of the track). I tried to do some basic gemometry to figure out what it might be, but decided to have another cup of coffee instead of attempting the higher math to figure out the loads with the dynamics of the car in motion! However, I imagine it's at least 1.3 or 1.4 Gs, i.e. the weight of your car and the load on the running gear and tires is multiplied by that factor.

I'll see you Oct and again in Dec at the 2 HPDEs here this fall!!!

Bob

Click for video that picture above came from


.

AU N EGL

What I did with my out side mirrors was aim them UP, so that when I was in the corners, I could see behind me. But on the straights or infield all I saw was sky.

Then just used the inside mirror for the straights.

BEZ06

Tom

I don't know about any of the other engines, but the oil starvation spikes that Dreamin found with the LS7 engine were only in left hand sweepers that sustained a G of greater than 1.0 G for longer than 4 seconds.

I have a Traqmate, and on the banking at Daytona I only sustain around .7 Gs. I'm on Hoosiers with an aggressive alignment for a regular road course (symetrical set up), and I'm only going about 150 to 155 on the banking. It's quite bumpy up there, so the lateral G displayed in the Traqmate data bounces around quite a bit because of the bumps, but because of the steep banking it only sometimes bounces above 1.0 on the banked sections.

A car with an asymetrical NASCAR type alignment for left turns only and on pure race slicks would generate a lot more Gs. I think even the DP cars that run the Daytona Rolex 24 probably pull more than 2 lateral Gs (I know they have tethers to their helmets to keep their head off their right shoulder - or the head restraint on their seat!).

I've got a fair amount of time on the high banks of Daytona in my C6 Z06 and have not experienced any oil pressure problems. HOWEVER.....I recently got an LPE tank that's going in before the next event there!!!





As I mentioned above, I run a regular road course alignment. I'm just an intermediate driver and don't push the car too hard, but if you watch the video linked in post# 9, you can see that you'll have HUGE fun with a stock Vette, or especially your T1 setup!!! If you're not doing the w2w racing event, like any HPDE you'll have to evaluate the risk/reward of how hard you want to push the car. The HPDE is not racing, so I stay well within my own driving limits (and that's WAAAAAY less than the capability of my car!!) so I can hopefully drive the car home.

Bob

AU N EGL

4 sec is way too long on any LSx engine.

LS3s and LS7 also had the HARD braking with keeping oil in the heads.

JimbeauZ06

As I mentioned above, I run a regular road course alignment. I'm just an intermediate driver and don't push the car too hard, but if you watch the video linked in post# 9, you can see that you'll have HUGE fun with a stock Vette, or especially your T1 setup!!! If you're not doing the w2w racing event, like any HPDE you'll have to evaluate the risk/reward of how hard you want to push the car. The HPDE is not racing, so I stay well within my own driving limits (and that's WAAAAAY less than the capability of my car!!) so I can hopefully drive the car home.

Bob [/QUOTE]

Don't know if you're going to the PCA HPDE, Oct 9-11, but so far it's looking like a lot of track time and not very many DE cars. It's being run by my friends in Jax and ORL (I used to live in Jax), and they're very accepting of other marques. Some good racing last year too with Leh Keen and some of the other Rolex drivers in the GT field for the Club Race. Thanks for your input. Hope to see you there!

AU N EGL

high banks are loads of fun, but not a place to push 9/10s

Have a good one guys

saibel

BEZ06

What software is being used at the top of the driving video in post 9. It details track position, rpm, speed etc. Looks very cool.

Thx

BEZ06

I have a Traqmate data-logger, and Traqmate has their own software called TraqStudio.

Their regular analytical software called Traqview will display the video alongside all the data the Traqmate collects, so it's a fantastic tool for seeing what you're doing on the track, and because you can log a lot of data about your car's systems (oil temp/press, coolant temp, throttle position, steering angle, brakes on/off or even brake line pressure, etc.) you can get info such as what's happening with your oil pressure during hard braking or left hand sweepers.

In addition to viewing the video alongside the data on your computer, it will also put that "dashboard" thingy on your video and let you select segments of video to save to video files to upload to a video hosting site like the video link in my post above.

However, that ability to save video files to video sites is just a gimmick compared to the value you get from seeing the video next to your track map and data on your computer. Without the video you might wonder why you were slow or off line going into a corner (you might not remember that on lap 3 you were stuck behind a slow guy). But with the video you can see that you were behind traffic and you took a different line to set up to pass when tracking out.

TraqStudio only works with Traqmate, but there are many other data-logger devices out there. If you have a different data-logger, you can still put that dashboard onto your video with a software called TrackVision (not associated with Traqmate).

Bob

saibel

Thank you. I am checking out their website. Is it an easy set up and install?

Steve

BEZ06

The Traqmate is very easy to install for basic data - GPS input for speed and track map, lateral Gs and fore/aft Gs for braking/accel. For that basic info you just secure it in the car, plug it into the cigarette lighter for power, and initially I just had the GPS antenna stuck in the middle of the hatch compartment with tape and it received GPS signals very well. For basic data you can set it up in a few minutes and move it from car to car easily and quickly.

However, to add RPM, and any other stuff from the car's systems, i.e. oil pressure, etc., you have to find where to tap into the car's sensor and run wires to the Traqmate unit.

There are some other data-loggers that have come out that you just plug into the OBD port for data from all the car's systems. One of those ones would be much easier to set up.

Do a search for data loggers or data acquisition and I'm sure you'll find a number of threads with info on other data-loggers.

Bob

John Shiels

Pocono is 16 degree banking and exit speed is 125 mph if you are fast, stock uprights are no problem. My car is not slammed but look at the sig picture on the banking compared to one on the straight. There is 1200 / 900 VBP springs.

argonaut

I was at pocono last weekend. Coming out of NASCAR turn 1 at about 100 (we were doing the south course and thus coming off the infield right into turn 1). This was my first time on the big bank (I've done turn 2 and 3 before). What I found hard was doing point bys. It takes a lot of effort to maintain the steering input and doing it with one hand is tough. Very fun though.