I just finished a Solosprint school at Mosport DDT. It's a short course with a number of tight 90 to 110 degree corners. The auto transmission of the GT held its own but I'm trying to figure out how to manage the transmission's idiosyncrasies.

I was using sport mode and mid corner to exit I was trying to use the throttle to set the car up to push/drift to the exit. The problem is that as you "bleed" the throttle in the car is still in the entry gear and the response is not enough to balance the car. Then as you get closer to wide open throttle it shifts down (with a slight lag) and the power rushes on causing the rear to break lose with over steer. Easy to catch but compromising your straightaway speed. Other times because of the lag you miss some acceleration time.

It would be interesting to hear any comments from experience roadracers on how they manage the auto transmission on tight corners (eg use the manual option, tune, changing the way they drive a corner).

The ESP was off.

Cheers
Matt

By the way, the G8 GT was a lot of fun to track, mine is bone stock. I'm not an experience road racer so don't have much to compare it to other than my gokart racing but the acceleration is a great, stock suspension very good, balance nice, understeer made it nice for newbies like me to catch trail breaking oversteer. This course isn't too hard on brakes but I had some pad fad. Day 1 was in the rain and with the weight and street tires the car stopped like a champ. Day 2 was in the dry and the tires and brakes suffered, but thank god for the squeal, it help guys like me know the limit. Add R compounds like the Toyo R888 and this thing will be awesome.

My first mods will be competition pads, brake ducts, and suspension related bushings were OEM needs improvement. R Compound, Suspension and power upgrades will come as my skills improve.

did you have ESP on? if so that will murder your out of corner response...you HAVE to have it off if you want the car to perform

did you have ESP on? if so that will murder your out of corner response...you HAVE to have it off if you want the car to perform

I agree, its a different car with ESP off vs on.

With regards to the corners, you'll have to manually shift it to really get it to do what you want. I tried the sport mode with AutoX, then just put it in 2nd and left it there and it worked much better in 2nd all around. Of course with a more open road course you'll need to do some shifting. You'll just have to learn when to shift at the top of the rev range to keep it from revving too high and (if you still have it) hitting the rev limiter.

Sorry, I should have said the ESP was off. I don't like shifting manually on the road course because I find the shifting a little slower than the sport auto mode. Frankly the auto is very good most of the time. What would be really great is to have a mode where you could tap it manually to shift down at/prior to the slow corner so you could modulate the throttle through the corner and then it would begin shifting in the autosport mode after you exit when the speed and rpm start to build.

What would be really great is to have a mode where you could tap it manually to shift down at/prior to the slow corner so you could modulate the throttle through the corner and then it would begin shifting in the autosport mode after you exit when the speed and rpm start to build.
Do you bog down if you flick the shifter to regular auto and back to autosport? How fast does the flick need to be to re-engage autosport?

I was afraid to do that under WOT but may have to try it as that seems like the only way to manually downshift underbraking before the corner and then get the sportauto mode to take over after the exit. I have no idea if there will be a lag or what it will do to throttle response. Guess I'll find out.:)

Find a tuner that is familiar with the transmission and have it reprogrammed.

You can switch it back and forth to go from manual back to the auto-sport and that may work well, just try it or you'll have to learn to shift manually. I don't know if tuning can make it behave the way you want it to.

I would recommend the trans tune. I got it on mine from Livernois and it makes the world of difference on the road course. When you up or down shift it happens right then and firm. Which is a good way to throttle steer. If you look at my Sebring video you can see the shifts but the sound is a little off.

.

I would recommend the trans tune. I got it on mine from Livernois and it makes the world of difference on the road course.


Mike,

Thank you for recommending our tune. The Sebring video is awesome! :driving::)

Matt, if you have any questions about the tune or our flash device, please let me know.

Regards,

Rick LeBlanc
Livernois Motorsports

dislike auto transmissions for doing track days and it's too bad Pontiac didn't offer a manual as an option on the GT.

It sounds like you're talking about maintenance throttle after the suspension takes a set and applying more power on corner exit. If you're anywhere near the traction limit and the auto transmission kicksdown to a lower gear by applying more power, you could lose the rear from the abrupt increase in torque. Likewise, you must also apply power to transfer weight to the rear in order for the car to maintain stability after the suspension is set. For this reason, choose a gear prior to turn in so that you're not at risk of dumping the rear from kickdown, still able to maintain speed through the apex, and have enough left to power through upon corner exit.

I don't feel simply changing shift points electronically will solve your problem as all corners on the track require different entry speeds, braking points, etc. This is where the manual transmission really shines as you can control shift points for certain conditions, hold a gear longer, and short shift.

To be fair, the closest I've ever driven to anything automatic on a track was an M3 with SMG-II and that really isn't your run-of-the-mill automatic anyway. However, the same basic suspension and driving dynamics apply regardless of transmission.

If you've only done a handful of track days, stay with your street tires as they're more forgiving, will give you lots of audible warning when near traction limits, and will help you to work on your lines and driving technique. Too many guys get in over their head with R-compounds before they're actually ready and end up in the wall from over-confidence.

I'm partial to manual transmissions for doing track days and it's too bad Pontiac didn't offer a manual as an option on the GT.

It sounds like you're talking about maintenance throttle after the suspension takes a set and applying more power on corner exit. If you're anywhere near the traction limit and the auto transmission kicksdown to a lower gear by applying more power, you could lose the rear from the abrupt increase in torque. Likewise, you must also apply power to transfer weight to the rear in order for the car to maintain stability after the suspension is set. For this reason, choose a gear prior to turn in so that you're not at risk of dumping the rear from kickdown, still able to maintain speed through the apex, and have enough left to power through upon corner exit.

I don't feel simply changing shift points electronically will solve your problem as all corners on the track require different entry speeds, braking points, etc. This is where the manual transmission really shines as you can control shift points for certain conditions, hold a gear longer, and short shift. I suppose manually choosing a gear than simply leaving it in auto should be of some benefit. Please correct me if you feel I'm mistaken.

To be fair, the closest I've ever driven to anything automatic on a track was an M3 with SMG-II and that really isn't your run-of-the-mill automatic anyway. However, the same basic suspension and driving dynamics apply regardless of transmission.

If you've only done a handful of track days, stay with your street tires as they're more forgiving, will give you lots of audible warning when near traction limits, and will help you to work on your lines and driving technique. Too many guys get in over their head with R-compounds before they're actually ready and end up in the wall from over-confidence. Oh yeah, it's not a race.

I don't feel simply changing shift points electronically will solve your problem as all corners on the track require different entry speeds, braking points, etc. This is where the manual transmission really shines as you can control shift points for certain conditions, hold a gear longer, and short shift.
I was suggesting manually shifting the auto, although you need a tune for the transmission to make the shifts much more precise, like my old Bimmer did. Worked like a charm for me.

Thanks for the input RJ and mbuono. I've been working with manually shifting the auto to get used to the direction of + and - and figuring out the approximate speed at or near redline. In my view they should be reversed. Anyway, I've got a pretty good idea that I'll spend most of my time at DDT in 2nd and 3rd with a little 4th at the end of the straight. Next time I'm there I'm going to try and use manual mode to see what happens. Hopefully the throttle will be a little more useful on the tight track. I'll also look into a tune to make manual shift quicker.

As an aside, it was pretty funny last weekend when my instructor kept telling me to get on the gas earlier. I had to explain to him that every time he said this I had been on the gas at least a few tenths before he asked for more gas. He figured it out when he felt the shift down and rapid rush of power a realized the trans took a little time to select a gear. We decided I might have to use some left foot braking.

Good point on R compound. I'll likely use them at Mosport DDT but I plan on using street tires on the big Mosport track and Shannonville until I've got more experience. There is the potential to have a very big off at Mosport.

Thanks again

Turning the traction control off will help you get on the throttle sooner without the engine management cutting power.

The other thing to watch out for is not getting addicted!

I'm partial to manual transmissions for doing track days and it's too bad Pontiac didn't offer a manual as an option on the GT.

It sounds like you're talking about maintenance throttle after the suspension takes a set and applying more power on corner exit. If you're anywhere near the traction limit and the auto transmission kicksdown to a lower gear by applying more power, you could lose the rear from the abrupt increase in torque. Likewise, you must also apply power to transfer weight to the rear in order for the car to maintain stability after the suspension is set. For this reason, choose a gear prior to turn in so that you're not at risk of dumping the rear from kickdown, still able to maintain speed through the apex, and have enough left to power through upon corner exit.

I don't feel simply changing shift points electronically will solve your problem as all corners on the track require different entry speeds, braking points, etc. This is where the manual transmission really shines as you can control shift points for certain conditions, hold a gear longer, and short shift. I suppose manually choosing a gear than simply leaving it in auto should be of some benefit. Please correct me if you feel I'm mistaken.

To be fair, the closest I've ever driven to anything automatic on a track was an M3 with SMG-II and that really isn't your run-of-the-mill automatic anyway. However, the same basic suspension and driving dynamics apply regardless of transmission.

If you've only done a handful of track days, stay with your street tires as they're more forgiving, will give you lots of audible warning when near traction limits, and will help you to work on your lines and driving technique. Too many guys get in over their head with R-compounds before they're actually ready and end up in the wall from over-confidence. Oh yeah, it's not a race.

+1 on these points..

Slush boxes drive me nuts at the track for these very reasons unless they have a full manual valve body in them. Even then, you just can't fine tune the attitude of the car in the corners as well with the throttle. There is no direct connection from the engine to the drive shaft unless the torque converter is locked up, so steering with the throttle just doesn't work as well.

An SMG gearbox is the way to go at the track, it's practically cheating.. Seamless upshifts on corner exit, no missed shifts, easier to trail brake into corners that might need a downshift, ect... On the street in day to day driving, I'd rather have a manual trans.

Definitely stay on street tires for the first year or so. You will learn far more on street tires if you are just starting track events. They give you more warning when they are unhappy with what you are doing, and the transition from "every thing is under control" to "OH SH*T!!" is wider, giving you more time to correct the situation. Another advantage is they they force you to be smooth with your steering inputs and really make you think about and hit your lines at every corner. A good driver on street tires will be faster than a so-so driver on sticky tires...

Even as an instructor, I've gone back to running street tires from time to time. Sure, they are not as fast, but they are more fun to toss around, plus when it rains, I'm first in line to go out. While everyone with shaved R compound tires is sitting in the pits or changing tires.

Hope this helps,
Mike

This is the advise you give your students?:slap:Slush boxes drive me nuts at the track for these very reasons...
Matt has a auto and is probably not going to tear it out. I've had plenty of students who drive manuals who couldn't heel toe downshift and would up set the balance of the car more than those driving autos.

So lets give him more good advise like you did about using street tires while just starting out.

This is the advise you give your students?:slap:
Matt has a auto and is probably not going to tear it out. I've had plenty of students who drive manuals who couldn't heel toe downshift and would up set the balance of the car more than those driving autos.

So lets give him more good advise like you did about using street tires while just starting out.

Sorry about that the autos drive me crazy comment, it wasn't helpful. It was a long day... You are right about people blowing heel-toe down shifts. My personal favorite is the 5th to 2nd downshift while still going over 90 mph.. That makes paper weights out of motors pretty quickly. The auto is easier to get into a corner, but I think more difficult to manage after turn in. As Matt gets more seat time, I think the characteristics of the trans will known better and driving style can be adjusted as needed to deal with corners that are between gears. Staying in manual mode would be the way to go.

If the trans is downshifting, then upshifting shortly after that on corner exit, one possible course of action would be to keep it in the higher gear all the way through the corner while in manual mode as long as that gear is good all the way to track out. This follows along with the philosophy of taking corners 1 gear higher than what seems right. This always seems slower from the drivers seat, but in a lot of cases, it ends up being faster. The concept behind this is to not limit your speed through the corner due to running into the rev limiter too soon or slowing down too much for the corner. As you get more experience, you will be carrying more speed through the corners anyway and need to be in the higher gear. This technique also places a premium on getting the line right. Since, as Matt noted, the car is not as responsive to throttle inputs, once committed to a line, there's not much you can do with the throttle to change it.

One of the hardest things for newer autocross/track drivers to learn is when to give up the speed and slow down. Slow corners really, really make you pay for over cooking them. For these, I like to reverse engineer the corner and think about what I have to do at turn in so I can be full throttle before the apex.

A couple other things that I have always recommended, ride with as many instructors as you can at track events. It gives you a chance to watch what they are doing at various corners and it gets you more seat time so you can tune into feeling what the car is doing. While you don't have a steering wheel to hang on to, you will begin to feel when traction is going away at either end of the car. Another bonus is that you get to ride in some pretty cool cars....

The other thing is to video tape your track sessions if you can. Reviewing those is a huge help especially if you can see the tach(if not, then take note of upshifts after a corner). Then you can try different things in a corner and see what rpm you are turning at track out. It will also help you decide what makes more sence on those corners that are between gears.

Mike

Practice, that's been working my best for me. My last AutoX event I used sport mode and played with the throttle to get the car to shift itself to the gear I wanted. Manual mode is probably still the best way to go but it all comes to down to practice and knowing the car.
And for general advice, I also got a lot better at my last event by going slower through the corner so I got through smoother and was able to get on the gas sooner and carry a good line coming out of the corner.

I've had plenty of students who drive manuals who couldn't heel toe downshift and would up set the balance of the car more than those driving autos.


I thought it was impossible when attempting it for the first time but it's essential to becoming a complete driver especially if you're looking to lower lap times. Newer drivers just need to adjust or bend the pedals slightly to set the spacing and height. You can also practice this driving on the street and you'll wonder how you ever downshifted without it.

My personal favorite is the 5th to 2nd downshift while still going over 90 mph.

I blew the rearend out of a Miata at Watkins Glen making this mistake on my second track day ever.

The other thing is to video tape your track sessions if you can. Reviewing those is a huge help especially if you can see the tach(if not, then take note of upshifts after a corner). Then you can try different things in a corner and see what rpm you are turning at track out. It will also help you decide what makes more sence on those corners that are between gears.


This is a HUGE learning tool. When you're on track, it might seem if you go any faster your going to crash until you review the on track session on video in a calm mental state. You'll see and hear where you're braking early, not getting back on the power fast enough, and what turns you're missing your marks on. It's also easy to get feedback from more experienced drivers on what you need to work on by having them review the video with you.


Practice, that's been working my best for me. My last AutoX event I used sport mode and played with the throttle to get the car to shift itself to the gear I wanted. Manual mode is probably still the best way to go but it all comes to down to practice and knowing the car.


Some people can't AutoX no matter what they're driving. People like me :). The official cone punter.

In the beginning, do whatever you can do to get seat time. Driving, riding along, whatever, it's all good. For auto cross, I highly recommend you let one of the club hot shoes drive your car with you riding along for some fun runs. There's not too many track organizations that let instructors drive student cars any more, but it's an option to consider of they do. This is usually an eye opening experience and serves several purposes... If at all possible, video tape these runs so you can compare your runs to the experienced driver's runs.
1. It gives you a reading on how close you are to the good drivers. As you get more experience, the gap starts coming down.
2. It shows that the car is plenty fast as it is if driven well. This should help to reduce the urge to start modifying things. At this point the car isn't the problem. Spend the money on going to more events to get more experience. I've seen people spend thousands on all the latest trick parts, only to still get smoked in raw times.. The only thing I would buy is another set of wheels/tires so you can use the worn set of STREET tires for autocross and track events while keeping the fresh rubber for the street. If you absolutely must tinker with something, play with tire pressures and alignment settings. Those 2 things alone can completely change the way the car drives and they are free.
3. It gives you a chance to feel the car at the limits. This is one of the skills that makes the fast guys/gals fast. They feel what the car is telling them, and can spend more time closer to the limits of traction without overcooking it. Understanding what the car is telling you is critical to getting faster.
4. Take note of how smooth all the inputs and transitions are. It's amazing how a run that feels slow, can be very fast. This is really hard to teach by just talking to someone and equally hard to learn by just listening, but just a couple rides is usually all it takes to drive the point home. Smooth is fast.

I thought it was impossible when attempting it for the first time but it's essential to becoming a complete driver especially if you're looking to lower lap times. Newer drivers just need to adjust or bend the pedals slightly to set the spacing and height. You can also practice this driving on the street and you'll wonder how you ever downshifted without it.
snip...
I heel toe down shift all the time. It's amazing how that can save wear and tear on the clutch and syncros as well.

How is the pedal placement for heel toe activities in the GXP?

Thanks for the tips guys. I did another track day and used the manual shift option in sport mode. Made a big difference. I downshifted before the corners and the throttle response through the corner and on exit was much better. The manual shifts were a little slow on the straights (I'll look into a tune in the future) but the response in the corners more than made up for this. I bounced it off the rev limiter a few times as the car is so quiet with the stock exhaust that it gets hard to hear the revs. Guess I need a shift light or louder exhaust.

Cheers,
Matt

How is the pedal placement for heel toe activities in the GXP?

It's a bit unusual, with the clutch and brake pedals sitting real close to the floor, and the gas pedal hung from the bottom. But the heel-and-toe works, once you get used to the pedals.

I thought it was impossible when attempting it for the first time but it's essential to becoming a complete driver especially if you're looking to lower lap times. Newer drivers just need to adjust or bend the pedals slightly to set the spacing and height. You can also practice this driving on the street and you'll wonder how you ever downshifted without it.

The trick there is that the name is misleading. Maybe if was the heel in the real old cars but nowadays it's "toe-and-right-side-of-foot".

You put the left side of the foot with the big toe on the right side of the brake pedal to brake, and then turn the foot sideways and forward, so that the right side of the foot hits the left side of the gas pedal. It's not difficult but practice on the street first. After a month or so of daily usage it will become easy. I wouldn't recommend starting it on the track.

..... Guess I need a shift light or louder exhaust....

Cheers,
Matt

And so it begins.... Warning.. Track driving is a progressive sickness... It starts with bolt ons to the street car and in it's more advanced state takes the shape of a truck, enclosed trailer, and a car that can no longer be driven on the street. :driving:

Glad to hear that things are improving. I'd vote for both the shift light and louder exhaust. Shift light to make it easier to gage progress of your corner exits and not bounce the rev limiter. Also, as you move to the faster run groups, more cars tend to be running very open exhaust systems and you will not be able to hear your motor if you are running near those guys. Exhaust just because these motors sound good, and a good one can also shave some weight.

The disease is progressing. Put new Hawk HP+ brake pads on, followed by Dunlop DirezzaSport tires; 200 UTQG. Awesome grip really fast, but on the road course they get a little greasy after a few laps. The heavy G8 also seems to be hard on tires. With so many right hand turns at Mosport the left hand tires took a beating. Will swap sides soon.

Here's a video from Mosport. Lots of high speed corners with elevation changes to keep things interesting. The big V8 liked the long straight and held its own against 09 audi rs4, c5 vette and 08 bmw m3. Would really like 275/40 tires to help keep all that weight in check in the corners.

http://www.vimeo.com/5634919

Sorry to hear of your disease, glad I don't have it. Or is denial one of the symptoms?
Nice video too. What did you use for the camera mount?

What did you use for the camera mount?

A broomstick:) Mounted between the grab handles in the back seat. Positioned the camera perfectly imo and it was the best I could do at midnight the night before. My friend's camera had a handlebar mount that fit the broomstick perfectly.

A broomstick:) .That's great!
I put the center rear seat down than attached my camera to the clip the holds the seat back up.

Great idea for a camera mount. The tires getting greasy after a few laps will just be a fact of life for a car this heavy on street tires, especially if they are full tread depth (new). All those tread blocks are squirming around in the corners, thus creating a lot of heat in the tire, which leads to that greasy feeling when the rubber compound overheats. If you have another set of wheels available, use which ever tires have the least amount of tread left, or get the tires shaved to 3/32nds before running them on the road the first time. Of course, this makes things interesting if it starts to rain since shaved or low tread depth tires will hydroplane very quickly.

One other area you will need to keep an eye on as you get faster is the brakes. I've not seen much feedback on how well they will hold up when pushed hard. The HP+ pads are a good choice for now. At some point in the future, you may have to look into extra cooling and/or going with a more track oriented pad that can take the heat. Of course, track pads don't work well when cold and will generally eat rotors very quickly if driven on the street. By quickly I mean a couple days. That was the only thing that killed my rotors on my old track car. Got lazy one weekend and decided to put the race pads on at home then drive to the track. Since VIR is only 70 miles from my front door, I drove home Saturday and made another round trip on Sunday. In that 280 miles of street driving, the rotors were worn well below minimum thickness. I was checking wear during the event and the track time had minimal effect on rotor thickness. In the 3 years I drove that car, that was the only time I had to change rotors. Went through a set of front pads every other track weekend.

I have several years experience in Formula 2000 and similar open-wheel formula cars on road circuits.

If being in the correct gear is an issue, go to the manual shift mode, then you can be certain you are in the desired gear and RPM at entry to the corner. Play around with it next time you are at the track to determine the best way to manage the torque band of the engine and what RPM you need at entry or when you go back to throttle at exit.

The street tires don't last long on the track. Having a separate set of race tires ends up cheaper. Besides, driving on the race tires is easier, there is less delay in the car's responses. If you're not going seriously after the quick lap times, a set of race tires can easily last a few years, with 30 events or so. The tires will harden after the first year and won't give that much grip but it still will be similar to street tires or a little better.

The race pads actually don't wear the rotors so much. They work at high temperatures, so they work by adhesion, not abrasion. Or at least that's my experience with Carbotech. It's the dual-purpose pads like HP+ that need to do both, and have a serious abrasive component to them. But they're not that bad either.

Orthm, any chance that you had the calipers sticking? The high temperatures tend to melt the lubricant out of the pins on the sliding calipers. Even the graphite lubricant doesn't work that well, requires regular cleaning. My Camaro also has these stupid rubber bushings around the pins, and they also tend to expand over time and pinch the pins.

I've got another video from Dunnville Autodrome.

http://www.vimeo.com/5688856

It's a flat course and is relatively forgiving if you make a mistake, unlike Mosport. The end of the straight is 180kmph into a right hander which can have consequences but I pushed it pretty hard in most other places to explore the limits a little. Dunlops were wicked fast on lap 2&3, by lap 4 I have to start reducing speeds in the corners.

Car still understeers on entry into most corners. I actually like the understeer at the end of the straight because I could go to the apex early and slide through the corner using the exit to scruff speed for entry to corner two. But generally doing a lot of trail braking. Strangely was getting oversteer on the fast laps on a few mid-corners which I put down to overheating the rear tires first with wheelspin on the exit of the previous few corners. Going to talk to a local suspension expert about dialing out some of the understeer. I'd really like to try a lose car on some of the tighter more forgiving courses (my skills aren't up to it on Mosport - I want understeer there).

Other thoughts:
The Dunlop grip is starting to show the weakpoints in the suspension. Body roll is up and the there is other "slop" which I put down to bushings.
Car is heavy but combined with the long wheel base makes things more forgiving.

Brakes well with the HP+ but orthm you are right, now that I'm getting faster the brakes are taking a beating. I was getting some pad fad on the end of the straight late in my sessions, the rotors aren't showing much wear but they do appear to be getting some microcracks on the surface; I assume from the heat. Hopefully the rotor won't crack soon.

You're right sab123, the plan is to get two sets of rotors. One for track days which will be used with true race pads. The other for getting to the track with OEM pads. The HP+ are my current compromise.

Future plans, over a couple of yearsr:
GPS datalogger
Pyrometer
Brake ducts
Hoosier R6, but still trying to figure out how to get a 9.5 inch rim all round.
Roll bar and race seat/belts
Reduce weight (any ideas how to get 500lbs out of this thing)
Another 100hp (cam/headers etc.)
OR
I may realize that this is a big heavy family sedan and I should really get a 2004 C5. But I really do like driving this big heavy family sedan.

The disease continues to progress.
Cheers,
Matt

I think that the corner-entry understeer is because of the way the multi-link rear suspension reacts to the weight transfer. Once I get a little on the gas, the car balances out and turns in nicely. So you may be better off with braking early and getting back on the gas early.

I use MaxQData for the data logger, it's probably the cheapest one out there. In the car I like to set it to show "time since last here", which is essentially your running lap time. You can also see if the number is increasing or decreasing, telling you if you're doing the current section better or worse than on the last lap. Another technique is to get an in-car camera, and later watch it with a stopwatch and write down the time by sectors. Just pick some signs at the side of the track for sector start marks, and click the stopwatch as they get to the edge of the frame. You'd be surprised that what felt slow in the car actually was 1 second faster than an all-exciting hot entry.

Summitracing.com sells infrared thermometers for around $60 (or maybe even cheaper now).

I've weighed my GXP recently, and it's weight is 4300 lbs with me, full-size spare, tools and other stuff in the trunk. Without me, spare and other stuff it should be about 4000 lbs, with a little over half-tank of gas.

For the brake ducts, on my race Mustang I use the 4" aluminum ducting from Home Depot, tied down with wire. Cheap and effective, and much more convenient to work with than the "proper" temperature-resistant plastic ducting (that stuff is a major pain to shape around all the moving parts). The difficult part on a street car is to find a place to pick up the air from, especially if the car sits as low as G8. On the race car I use the holes in the bumper left from the fog lights but you would not want to take out your fog lights for that.

By the way, I'm considering selling my Mustang, so let me know if you'd be interested :-)

I think that the corner-entry understeer is because of the way the multi-link rear suspension reacts to the weight transfer. Once I get a little on the gas, the car balances out and turns in nicely. So you may be better off with braking early and getting back on the gas early.

I use MaxQData for the data logger, it's probably the cheapest one out there. In the car I like to set it to show "time since last here", which is essentially your running lap time. You can also see if the number is increasing or decreasing, telling you if you're doing the current section better or worse than on the last lap. Another technique is to get an in-car camera, and later watch it with a stopwatch and write down the time by sectors. Just pick some signs at the side of the track for sector start marks, and click the stopwatch as they get to the edge of the frame. You'd be surprised that what felt slow in the car actually was 1 second faster than an all-exciting hot entry.

Summitracing.com sells infrared thermometers for around $60 (or maybe even cheaper now).

I've weighed my GXP recently, and it's weight is 4300 lbs with me, full-size spare, tools and other stuff in the trunk. Without me, spare and other stuff it should be about 4000 lbs, with a little over half-tank of gas.

For the brake ducts, on my race Mustang I use the 4" aluminum ducting from Home Depot, tied down with wire. Cheap and effective, and much more convenient to work with than the "proper" temperature-resistant plastic ducting (that stuff is a major pain to shape around all the moving parts). The difficult part on a street car is to find a place to pick up the air from, especially if the car sits as low as G8. On the race car I use the holes in the bumper left from the fog lights but you would not want to take out your fog lights for that.

By the way, I'm considering selling my Mustang, so let me know if you'd be interested :-)

Are you running Griggs stuff on your Mustang?

Are you running Griggs stuff on your Mustang?

No. I run it in the class that allows the least modifications, to keep the costs in check. Actually, the rear lower control arms might be Griggs, I don't remember. It's got the Steeda panhard bar, for which I eventually had to reinforce the mount. Every Steeda part I've seen so far had some screw-up. The rules allow the torque arm conversion, so I'm thinking of going with the Maximum Motorsports rear suspension for the next year: torque arm, panhard bar, adjustable sway bar.

I use MaxQData for the data logger, it's probably the cheapest one out there.

Summitracing.com sells infrared thermometers for around $60 (or maybe even cheaper now).

For the brake ducts, on my race Mustang I use the 4" aluminum ducting from Home Depot, tied down with wire.

By the way, I'm considering selling my Mustang, so let me know if you'd be interested :-)

Thanks for the tips. Sorry, not looking for a Mustang right now.

i feel the best for road racing is to use manual shift and tune you shifts so theyre firm and precise. you cant set yourself up for an apex with the auto. it aint gonna happen

Be careful when taking the auto G8 to the track. I recently took my C6 Vette paddleshifter to Eagles Canyon Raceway in Texas and discovered something scary. The trans fluid temp reached 269 degrees while pushing it slightly hard. I do not now at what temp the fluid will oxidize, but I'm certain those temps can't be good for it. I believe it is the same tranny in my G8. I do know there is a lot more room for a tranny cooler in the G8 than in the C6 and would be a good investment if taken to the track for more than spirited driving. You can see just how hard I pushed it to get these high temps.

http://www.youtube.com/watch?v=PXtkMBaJvlM

Be careful when taking the auto G8 to the track. I recently took my C6 Vette paddleshifter to Eagles Canyon Raceway in Texas and discovered something scary. The trans fluid temp reached 269 degrees while pushing it slightly hard. I do not now at what temp the fluid will oxidize, but I'm certain those temps can't be good for it. I believe it is the same tranny in my G8. I do know there is a lot more room for a tranny cooler in the G8 than in the C6 and would be a good investment if taken to the track for more than spirited driving. You can see just how hard I pushed it to get these high temps.

http://www.youtube.com/watch?v=PXtkMBaJvlM
That's not hard to believe, now image what your oil temps are.
The GXP comes with trans cooler and I added and oil cooler.
Nice video BTW! A little different than Sebring...smooth track and no walls.

I do have the factory trans fluid cooler built into the radiator. I plan to add another one as soon as I figure out where to put it. The track is nice and smooth mostly. I normally run my vintage Formula Ford there, it was nice to be able to see farther from a higher vantage point but the car felt as large as a tank. I was 16 seconds slower in the Vette. The camera was a Sony T-900 pocket sized camera attached to the windshield with a Best Buy suction cup mount. I was jazzed by the video quality compared to my Go Pro which fails to work most of the time. As soon as I take the G8 out I can compare the lap times from the video. Sometime in the winter months.

More video fun from my SoloSprint race at MIR. Lots of wind noise so be careful of the volume, but you can hear the angry V8 at bit. GoPro camera mounted on the hood.

http://www.vimeo.com/6256551

Learned a few things using my new pyrometer (with probe). Track temp 30C (86F). The Dunlop Z1 StarSpecs 37psi cold front and back (left side), 36 right side, resulted in 45psi hot all round. Temps about 56C front and rear at the end of 5 laps. The car did feel pretty balanced in the high speed corners but the outside of the tires were a bit hotter (maybe needs more negative camber). Dunlops get maximum grip on hot lap 2 and then get slower (must be an autocross tire).

Still have no idea what the target temp is for these tires (I understand race tires target about 82C and street tires are less) but given they get slower after the 2nd lap the target temp most be relatively low. The short sessions keep the tires from overheating that's for sure.

Still kept a margin for error in corners 1,2, 4 and 8 but getting more confident and faster. The back end did come around in turn 2 early in the day after I missed my turn in by about 10 feet while trying a faster entry. After looking at the inside wall I told myself to get a little more gas and be careful not to use too much opposite lock. Caught it - this was a good learning experience but reminded me to treat this course with respect the rest of the day.


Matt

Thanks for the video...good to see someone else running the Dunlops. Yes, they are an autocross tire designed to grip cold and they may get slick off when they get too hot. For autocross I run around 39PSI front, 42 rear and that works pretty well, any higher they get too hard and won't stick.