Going to 75-80 Dragway Friday - tips and advice appreciated

[SVTKen]

I'm planning to go to the 75-80 Dragway (75-80 Dragway Homepage) in Monrovia, MD this Friday (Sept. 6) for some test and tune runs. It opens at 4:00 for tech inspection and I believe that the first test and tune runs will begin at 5:00 if all goes on schedule. If anyone is interested in coming out for this, please let me know. I plan to get there when the gates open. I'm ready to make my first timed run in the Shelby, so this will be a historic event LOL

I would appreciate any advice you guys could give me as well. I know the basic stuff like how to set up launch control and how to disable the traction control for the burnout. I also know about the "lockout" during shifting if you try to shift too fast. It seems like a semi-fast speed shift with a quick lift off the throttle works pretty well, but powershifting is out! At least that has been my experience. One thing I noticed when using the launch control on the street is that there is a lot of wheel spin, and that's without even enabling the sport mode. This is at the lowest RPM setting of 3000 RPM. Am I going to have a similar problem at the track? I was planning to heat the tires well (something I haven't done on my street launches) and use sport mode during the launch, but don't want to look like a fool roasting the tires. I understand that I'm supposed to just keep my foot planted during the entire launch, but when I start getting wheelspin, my instinct is to lift off the throttle a bit. Should I try to modulate the throttle and lift a little or just let the launch control system and traction control do it's job? Since it will be my first time, I really want to test out the launch control and experiment with it to see how well it works. I figure I will start with a 3000 RPM launch and work my way up in 200 RPM increments until I can get the best launch. On my next trip to the track, I will try some manual launches without the launch control.

I plan to just leave the tire pressure at the factory recommended levels for my first time out so if I try changing things the next time I go, I will undestand the differences. Should I go with 35 psi all around, or have any of you had better luck with lower rear tire pressure? I've read mixed information here regarding the recommended rear tire pressure for the best traction results at the drag strip. I'm running with the stock tires.

I've been on this forum for a while and really have learned a lot from everyone on here. Any tips and advice you can give me as a noob at the track with my Shelby would be appreciated. I raced my Procharged '97 Cobra and my SRT8 at the strip quite a bit, but the Shelby has it's own unique personality. Thanks for all the great info and advice.

 

[Lethalchem]

Your tires will hook better at the track for 2 reasons: You will heat them prior to launch, and the track will be prepped better than a dusty street. I would follow your plan and just keep it planted for the first run. I suspect you will pull anywhere from 2.0-2.2 with that method.

 

[Njtony]

Best thing to do IMO is try to get off the clutch as quick as possible without dumping it. This seems to help avoid some of the issues with the clutch protection that come up at the strip. Stock goodyears need heat and dropping the pressure to 20 or so worked for me.

 

[Lethalchem]

Best thing to do IMO is try to get off the clutch as quick as possible without dumping it. This seems to help avoid some of the issues with the clutch protection that come up at the strip. Stock goodyears need heat and dropping the pressure to 20 or so worked for me.

Yeah I fought the stumble/bog more than tire spin. :bash:

 

[SVTKen]

edit - duplicate post

 

[SVTKen]

Best thing to do IMO is try to get off the clutch as quick as possible without dumping it. This seems to help avoid some of the issues with the clutch protection that come up at the strip. Stock goodyears need heat and dropping the pressure to 20 or so worked for me.

Yep, a quick smooth release is what I try to do. That seemed to work best with my previous Cobra as well. What exact pressure did you have your rear tires set? Did you make any runs with the pressure set closer to 35 psi for comparison. I've never had much more success with less than 27 psi at the strip on any cars on street tires/factory rims.

Yeah I fought the stumble/bog more than tire spin. :bash:

With the technique I've been experimenting with on the street, I release the clutch quickly, but I don't dump it. If there is a bog, I don't notice it much. I get more wheel spin than I would expect though. I was expecting the traction control to be more intrusive, especially without enabling the sport mode. I suppose the track will be completely different with the sticky surface (hopefully!) and nice hot tires. How would you guys compare your technique on the street vs the track? I haven't even tried launch control with sport mode on the street. I figured that would just result in even more wheel spin.

 

[Lethalchem]

With the technique I've been experimenting with on the street, I release the clutch quickly, but I don't dump it. If there is a bog, I don't notice it much. I get more wheel spin than I would expect though. I was expecting the traction control to be more intrusive, especially without enabling the sport mode. I suppose the track will be completely different with the sticky surface (hopefully!) and nice hot tires. How would you guys compare your technique on the street vs the track? I haven't even tried launch control with sport mode on the street. I figured that would just result in even more wheel spin.

For me, same technique on both the street and track resulted in:
Street = spin
Track = Bog

Here are a few vids of my VERY sloppy first runs ever in the Shelby. I did just about everything wrong.

3000rpm LC setting. Bogged launch, missed 2nd, spun 2nd when I got it in gear, then granny shifted third. That was a 2.11 60'.

2013 Shelby GT500 First Track Day (3/16/13) - Run 1 on Vimeo

2nd run: 3200 rpm, 25psi tire pressure. Bogged. 2.24 60'

Shelby GT500 Practice - Run 2 on Vimeo

3rd run: 3300 rpm, 25 psi. Still Bogged 2.18 60'

2013 Shelby GT500 First Track Day - Third Pass on Vimeo

Those were my very first 3 passes ever in the car. My best short time of the day ended up being a 2.07 and I never stopped bogging (right lane).

 

[biminiLX]

I personally liked running with LC or any aids but I will never go back on stock tires too frustrating.
I get wanting to do it, I also made it a goal to run 11s 100% stock and did that on my third pass. First 2 passes I tried LC first at 3400 then at 3000 and it just spun thru first. I bogged it intentionally the third pass with no aids and it still spun hard after the 1-2 shift but went 11.94@125 2.2 60'
Good luck and have fun.
-J

 

[biminiLX]

For me, same technique on both the street and track resulted in:
Street = spin
Track = Bog

Here's a few vids of my VERY sloppy first runs ever in the Shelby. I did just about everything wrong.

3000rpm LC setting. Bogged launch, missed 2nd, spun 2nd when I got it in gear, then granny shifted third. That was a 2.11 60'.

2013 Shelby GT500 First Track Day (3/16/13) - Run 1 on Vimeo

2nd run: 3200 rpm, 25psi tire pressure. Bogged. 2.24 60'

Shelby GT500 Practice - Run 2 on Vimeo

3rd run: 3300 rpm, 25 psi. Still Bogged 2.18 60'

2013 Shelby GT500 First Track Day - Third Pass on Vimeo

Those were my very first 3 passes ever in the car. My best short time of the day ended up being a 2.07 and I never stopped bogging (right lane).

That last pass would have been an 11 for sure :rockon: sounds like the track was hooking if bogging on stock tires.
-J

 

[NvrEnfHP]

clutch protection = Bog, you have to slip the clutch, I learned the hard way.

 

[SVTKen]

Thanks for the tips guys. This is all great information and good to know in advance. It sounds like I'll have to experiment with the clutch release. I'll just start at 3000-3200 RPM and work my way up if the track is hooking. I hope I don't get the bog you guys are describing. If I can pull off a low 2.0 60 ft time and an 11 second run I'll be thrilled, but I'm going to temper my expectations since I know I've got a lot to learn on my first tries

lethalchem - I noticed your track only goes 1000 ft. Do you know how your 1000 ft time would translate to a 1/4 mile time if you ran it a 1/4 mile instead?

 

[biminiLX]

On the slip he posted I would have expected an 11.80 or slightly better.
-J

 

[Lethalchem]

clutch protection = Bog, you have to slip the clutch, I learned the hard way.

I wasn't slipping the clutch on my runs BECAUSE I felt clutch slip would kick in the clutch protection. I was confused about the bog in my videos because I was expecting wheel spin like on the street. I never got the bog on the street, just spin. I should have made a pass or two with all nannies off and tried to pedal it a bit and see how it performed, but I was really just there on this date to get a general feel for the car and it's modes.

lethalchem - I noticed your track only goes 1000 ft. Do you know how your 1000 ft time would translate to a 1/4 mile time if you ran it a 1/4 mile instead?

While not an EXACT translation, the general rule of thumb at this track is to add around 1.8 sec to your 1000' time when running these speeds, so my guess would be that my 9.9 sec 1000' pass would have come in somewhere around the 11.7-11.8 range.

 

[SVTKen]

One thing I'm a little bit surprised about is that it appears people are having difficulty getting better than 2.00 60 ft times. I've been searching through the drag times thread, and most 60s are in the 2.1 - 2.2 range. A 2.1 - 2.2 60 ft is the worst time I ever got in my Chrysler 300C SRT8. It usually ran a 1.9-2.0, but it was an automatic (without any launch control) and I suppose that helps.

 

[Daffy]

If I can manage to get out early I'll come to 75/80, if I can get out I'll swing by & grab my helmet & camera. Never did the 1/4 in my '11 so it might be fun to take the '14, just hit 2K miles this morning. I've been a road course guy now for yrs so I'm well outta practice, but what the hec ... I'll look for you if I can make it. I have a silver/black.

 

[SVTKen]

If I can manage to get out early I'll come to 75/80, if I can get out I'll swing by & grab my helmet & camera. Never did the 1/4 in my '11 so it might be fun to take the '14, just hit 2K miles this morning. I've been a road course guy now for yrs so I'm well outta practice, but what the hec ... I'll look for you if I can make it. I have a silver/black.

That sounds great! Nobody in my family and only one of my friends is interested in drag racing or cars. It will be fun to meet a fellow forum member. Hope you can make it out. I'll be there early, hopefully when the gates open at 4:00. My car is Deep Impact Blue with black stripes. We'll probably be the only guys there with 13/14 GT500s


One more question for the group:

Will I be making a big mistake just leaving the rear tire pressure at 35 psi? My main goal tonight is to get a feel for the car and try to get the most out of the launch control. Next time, I plan to do more manual launches and perhaps tinker with the tire pressure. My thought is that anything less than high 20s psi for the rears is not going to help much because of the short sidewalls. Please give me your thoughts.

 

[Willie2]

I may be wrong but I think LC is engineered to work with factory tire pressure..

 

[Lethalchem]

One thing I'm a little bit surprised about is that it appears people are having difficulty getting better than 2.00 60 ft times. I've been searching through the drag times thread, and most 60s are in the 2.1 - 2.2 range. A 2.1 - 2.2 60 ft is the worst time I ever got in my Chrysler 300C SRT8. It usually ran a 1.9-2.0, but it was an automatic (without any launch control) and I suppose that helps.

Slipping the clutch out of the hole has always been the method for me to get my best times when using street tires. If you take that option away (which the clutch protection program does) it makes it very difficult to get a good launch without the nannies. Using the nannies has it's own disadvantages too though, so I think that's why you're seeing most guys stuck in the same range. And yes, launching an automatic is totally different. lol

Still, guys on here have cut short times in the 1.8-1.9 range so it can be done, but I think it's more track prep than anything else because just about everyone is using mode 7.

Will I be making a big mistake just leaving the rear tire pressure at 35 psi? My main goal tonight is to get a feel for the car and try to get the most out of the launch control. Next time, I plan to do more manual launches and perhaps tinker with the tire pressure. My thought is that anything less than high 20s psi for the rears is not going to help much because of the short sidewalls. Please give me your thoughts.

I saw no benefits when changing my tire pressures around.

 

[Darth Racer]

Forget street tires; use slicks

 

[SVTKen]

What a disappointment. I drove an hour to the track and fought some pretty bad traffic to get there just to find out that the track was closed "DUE TO POWER FAILURE AT THE TRACK".

On the positive side I did get to meet Dave (Daffy) and another group of guys and we stood around for a while and talked about cars. Nice meeting you Dave!

I'll have to check all the track schedules and see when I can try again.