Hi guys,
what pressure are you autocrossing your Falken Azenis RT-615 tires? I've been running 38 than going down 2 lb.s per run till 32. 32-34 seems the best but not sure if it's the tires just getting good heat and me getting used to the course or if they are actually sticking better.
Air pressure
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Dan Atsma
- Roadster Nut
- Posts: 50
- Joined: Mon Dec 18, 2006 10:37 pm
- Location: Grandville Mi.
- Contact:
Air pressure
Dan (Toad)
69 2000 Roadster
67 Corvette Coupe
Old Motor Bikes
69 2000 Roadster
67 Corvette Coupe
Old Motor Bikes
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SLOroadster
- Roadsteraholic
- Posts: 5360
- Joined: Sun Dec 08, 2002 2:53 am
- Location: Napa Ca
Dan,
I was actually down as low as 26 in the front and 28 in the rear. With a half tank of gas it wasn't good, but it was far better than running the high pressure that you are. I started high to stiffen the sidewalls, but it made the car skate around. It was too slippery. I hate to say it, but the tires are not the hot setup for a roadster. They seem to work pretty well for a Miata, but they are the wrong creature for going fast on an autoX course in a roadster. Honestly, I think the first generation Azenis were a better tire. The sidewalls were stiffer. If you can afford a second set of wheels, spend the $ for a set of Kumho V710s and you won't be disappointed. Its like a pass to the front of the field. To see what I mean, watch my in car video that I posted in the "And the winner is..." thread. That was a slow lap, but it was still pretty fast all things considered. I did the entire course in 2nd gear, so when it sounds wound out, you can imagine the amount of grip through the corners I have now.
How did/is your season going?
Will
I was actually down as low as 26 in the front and 28 in the rear. With a half tank of gas it wasn't good, but it was far better than running the high pressure that you are. I started high to stiffen the sidewalls, but it made the car skate around. It was too slippery. I hate to say it, but the tires are not the hot setup for a roadster. They seem to work pretty well for a Miata, but they are the wrong creature for going fast on an autoX course in a roadster. Honestly, I think the first generation Azenis were a better tire. The sidewalls were stiffer. If you can afford a second set of wheels, spend the $ for a set of Kumho V710s and you won't be disappointed. Its like a pass to the front of the field. To see what I mean, watch my in car video that I posted in the "And the winner is..." thread. That was a slow lap, but it was still pretty fast all things considered. I did the entire course in 2nd gear, so when it sounds wound out, you can imagine the amount of grip through the corners I have now.
How did/is your season going?
Will
Sorry, I find modern engine swaps revolting. Keep your G, R, or U series in your Roadster!
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fixitman04
- Roadsteraholic
- Posts: 726
- Joined: Sat Nov 12, 2005 12:29 am
- Location: grand forks nd
tire pressure is an individual setup issue in my opinion.
the best way to determine what is best is to do a little contact patch testing on warm tires.
the short and simple method that i use is this:
1: warm the car ,brakes,and tires up with a few hotlaps
2: take a tire paint pen and run a stripe from 1"down on the sidewall of the tire across the tread and down the other sidewall on all four tires.
3: after the paint has dried (while the tires are still warm though) make 3 hard laps.
4:inspect the stripes.
a. if the stripe has worn off of the sidewall, you need more air as the contact patch is rolling over the sidewall
b. if the stripe has not worn all the way to the shoulder you need less air as you are shorting yourself usable contact patch
5: repeat until the contact patch is completely across the tread but not on the sidewall. be shure to take notes as to car condition(ie fuel level,suspension settings), track conditions(track temp,air temp ect.) and of course tire pressure and wear.
6: do this every weekend of racing as it will change depending on conditions and tire wear, but the notes will help
i usually start at 35 psi and work down, but as you learn your setup you will be able to start closer to your goal(hence the notes)
the best way to determine what is best is to do a little contact patch testing on warm tires.
the short and simple method that i use is this:
1: warm the car ,brakes,and tires up with a few hotlaps
2: take a tire paint pen and run a stripe from 1"down on the sidewall of the tire across the tread and down the other sidewall on all four tires.
3: after the paint has dried (while the tires are still warm though) make 3 hard laps.
4:inspect the stripes.
a. if the stripe has worn off of the sidewall, you need more air as the contact patch is rolling over the sidewall
b. if the stripe has not worn all the way to the shoulder you need less air as you are shorting yourself usable contact patch
5: repeat until the contact patch is completely across the tread but not on the sidewall. be shure to take notes as to car condition(ie fuel level,suspension settings), track conditions(track temp,air temp ect.) and of course tire pressure and wear.
6: do this every weekend of racing as it will change depending on conditions and tire wear, but the notes will help
i usually start at 35 psi and work down, but as you learn your setup you will be able to start closer to your goal(hence the notes)
67.5 srl-311-00407 u20
desperately looking for a 67.5 body that is rust free... id settle for any low window tub
desperately looking for a 67.5 body that is rust free... id settle for any low window tub
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Dan Atsma
- Roadster Nut
- Posts: 50
- Joined: Mon Dec 18, 2006 10:37 pm
- Location: Grandville Mi.
- Contact:
Thanks for the imput guys, as for my season Will we did pretty good, there are 2 RX7's we can't seem to consistantly beat in our class. I put in a Kirkey race seat and put the battery in the trunk on the passenger side before the last race and then I ended up not being able to go but my brother took a first. We now have an 1" of snow and 4" more coming this weekend. 
How's your season going?
How's your season going?
Dan (Toad)
69 2000 Roadster
67 Corvette Coupe
Old Motor Bikes
69 2000 Roadster
67 Corvette Coupe
Old Motor Bikes
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SLOroadster
- Roadsteraholic
- Posts: 5360
- Joined: Sun Dec 08, 2002 2:53 am
- Location: Napa Ca
Dan,
My season is done for the year. I finished 2nd in the class points championship. Next years season starts the end of January, I don't think I will be making many changes for next year. I have a winning car now (the last 2 events a friend won class in my car. I finished 2nd to him just .02 tenths of a second behind in the 2nd event, and had an off day in the last one finishing 6th. My friend Tim won by a safe margin.) If you check out my "And the winner is..." post I have some pictures and some in car footage posted.
If you can run a set of DOT R-compounds, the V710 Kuhmos are the hot setup. With a set you should be able to put the hurt on a large portion of the overall group.
Will
My season is done for the year. I finished 2nd in the class points championship. Next years season starts the end of January, I don't think I will be making many changes for next year. I have a winning car now (the last 2 events a friend won class in my car. I finished 2nd to him just .02 tenths of a second behind in the 2nd event, and had an off day in the last one finishing 6th. My friend Tim won by a safe margin.) If you check out my "And the winner is..." post I have some pictures and some in car footage posted.
If you can run a set of DOT R-compounds, the V710 Kuhmos are the hot setup. With a set you should be able to put the hurt on a large portion of the overall group.
Will
Sorry, I find modern engine swaps revolting. Keep your G, R, or U series in your Roadster!
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Dan Atsma
- Roadster Nut
- Posts: 50
- Joined: Mon Dec 18, 2006 10:37 pm
- Location: Grandville Mi.
- Contact:
Hey Will,
Your car looks great on the course,
I found some videos of the last run of the season of our car, keep in mind it was 35 degree's out, It's a interesting place to run. It's at a our local dragstrip in the parking & staging area. Next summer they are talking about doing a dual run - track/strip:
I also have some newer shots of the car, the last ones are at a speed event we did in NC at the ECTA:
http://picasaweb.google.com/danatsma/Da ... Enterprise
Your car looks great on the course,
I found some videos of the last run of the season of our car, keep in mind it was 35 degree's out, It's a interesting place to run. It's at a our local dragstrip in the parking & staging area. Next summer they are talking about doing a dual run - track/strip:
I also have some newer shots of the car, the last ones are at a speed event we did in NC at the ECTA:
http://picasaweb.google.com/danatsma/Da ... Enterprise
Dan (Toad)
69 2000 Roadster
67 Corvette Coupe
Old Motor Bikes
69 2000 Roadster
67 Corvette Coupe
Old Motor Bikes