Cadillac Owners Forum banner

1 - 12 of 12 Posts

·
Registered
2018 ATS-V 6sp MT sedan
Joined
·
244 Posts
Discussion Starter #1
I went to a Shelby Club track event at the Streets of Willow Springs this weekend. I was able to improve my lap times by 5 seconds from last year with a best lap of 1:30.18 in damp conditions. Next time I'll try to break 1:30. I was using Hankook Ventus R-S4 tires 265/35R18 and 285/35R18 and I am pleased with how they performed.
Here is my video.
Enjoy.
Blessings.
Roy.
 

·
Registered
2016 ATS-V sedan 6 speed manual
Joined
·
346 Posts
Nice! I'm starting to feel more comfortable with my stock size RS-4s, too - at this last weekend's autocross at the Seneca Army Depot runway we ran essentially the same course as the Sunday course for the recent Champ Tour there. I nearly reined in the Camaro Z/28 1LE by trusting the tires (and car) more even in slightly damp conditions. I used launch control for my last run which was, ummm, interesting given the bit of moisture which seemed to confuse it. Only about 50 feet before the first turn so it didn't really matter.

What tire pressures are you running? I know I have more front camber than you (I've got -2.4) and was at about 45f/42r for my best run. Rollover on the rear seems to indicate I may want to raise the rear pressure a bit - maybe even all the way around? The owner's manual suggests even pressures all around for track use...

BTW, I find editing my videos is useful, changing the gamma setting a bit to lighten the course since the sky tends to cause the whole scene to darken.

http://cloud2.zoolz.com/s-ul9FurWh
 

·
Registered
2018 ATS-V 6sp MT sedan
Joined
·
244 Posts
Discussion Starter #5
Nice! I'm starting to feel more comfortable with my stock size RS-4s, too - at this last weekend's autocross at the Seneca Army Depot runway we ran essentially the same course as the Sunday course for the recent Champ Tour there. I nearly reined in the Camaro Z/28 1LE by trusting the tires (and car) more even in slightly damp conditions. I used launch control for my last run which was, ummm, interesting given the bit of moisture which seemed to confuse it. Only about 50 feet before the first turn so it didn't really matter.

What tire pressures are you running? I know I have more front camber than you (I've got -2.4) and was at about 45f/42r for my best run. Rollover on the rear seems to indicate I may want to raise the rear pressure a bit - maybe even all the way around? The owner's manual suggests even pressures all around for track use...

BTW, I find editing my videos is useful, changing the gamma setting a bit to lighten the course since the sky tends to cause the whole scene to darken.

http://cloud2.zoolz.com/s-ul9FurWh
My alignment shop was able to coax some more camber so now I'm at -2.2 LF and -3.0 RF. Not sure why the LF can't get more, manufacturing tolerance differences I assume between left and right.
My R-S4's are 265 front and 285 rear, which is slightly wider than the stock 255, 275.
Dead cold sitting overnight in the garage the tire pressure was 35 psi all around.
Attached is my tire telemetry sheet from my last run of the day where I was going fastest.
Pressures started at 38ish at the beginning of the session and went up +10 psi after 20 minutes of hard running. LF went up the most due to the configuration of the track (the hardest corners are right turns).
Enjoy.
Blessings.
Roy.
Tire stats.png
 

·
Registered
Joined
·
44 Posts
I went to a Shelby Club track event at the Streets of Willow Springs this weekend. I was able to improve my lap times by 5 seconds from last year with a best lap of 1:30.18 in damp conditions. Next time I'll try to break 1:30. I was using Hankook Ventus R-S4 tires 265/35R18 and 285/35R18 and I am pleased with how they performed.
Nice driving as always, Roy! I'm curious how you felt about the track given the weight of our cars. I haven't been to Streets for a while--I was never a big fan of that track and really only had fun in much lighter cars. (Kid you not, I tracked a Smart Car there once, which was possibly the most fun I've ever had at the track.)

Also, did you notice any roll-over with those tire sizes? I'm running PS4S right now, but I've been looking at some other tires that only come in the bigger sizes (265/285) like you ran.
 

·
Registered
2018 ATS-V 6sp MT sedan
Joined
·
244 Posts
Discussion Starter #7
Nice driving as always, Roy! I'm curious how you felt about the track given the weight of our cars. I haven't been to Streets for a while--I was never a big fan of that track and really only had fun in much lighter cars. (Kid you not, I tracked a Smart Car there once, which was possibly the most fun I've ever had at the track.)

Also, did you notice any roll-over with those tire sizes? I'm running PS4S right now, but I've been looking at some other tires that only come in the bigger sizes (265/285) like you ran.
Thanks. This was the 6th time I've run this track configuration (CW with the bowl) over the past 13 years. Last weekend was my personal best. Better than I was able to run with my 2001 Corvette on Hoosiers. The Cadillac is heavy and the track is tight. Fortunately most of the cars I was running with were also heavy. I felt much more comfortable this time compared to last year. So I had lot's of fun and no one passed me or was stuck on my bumper all weekend.

My Hankooks appear to fit on the rims just fine and my wear line is just above the little triangles on the sidewall so I think the tires are not rolling over too much and are not overinflated. I found this thread over on a Porsche forum (https://rennlist.com/forums/964-for...osed-to-reach-on-the-sidewall-tire-press.html)

Enjoy.
Blessings.
Roy.
 

·
Registered
2019 ATS-V, Black Raven, all options, no mods
Joined
·
82 Posts
Nice driving!

You were right on the tail of that 911. I kept wondering when he was gonna point to pass.

I've never driven that track CW. But to be honest, it seems like CCW would be more enjoyable. Only because you get to utilize all that power a lot more going up the hill to the bowl.
 

·
Registered
2018 ATS-V 6sp MT sedan
Joined
·
244 Posts
Discussion Starter #9
Nice driving!

You were right on the tail of that 911. I kept wondering when he was gonna point to pass.

I've never driven that track CW. But to be honest, it seems like CCW would be more enjoyable. Only because you get to utilize all that power a lot more going up the hill to the bowl.
Thanks. With the LA Shelby Club, even in the advanced run group, they only allow passing on the front straight, on the left, only with a point by. So I had to wait a whole lap before I could pass that Porsche.
 

·
Registered
2016 ATS-V Sedan 6MT
Joined
·
352 Posts
With the LA Shelby Club, even in the advanced run group, they only allow passing on the front straight, on the left, only with a point by.
That's a little overcautious since back straight is a fairly safe place to pass as well, but it beats having 30+ cars in the same group and people going wild at Extreme Speed events.
 
1 - 12 of 12 Posts
Top