The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

HOOSIER R100 RADIAL SLICK PRESSURES HOT/COLD (NOT DOT SLICK)

344
0
Any experience out there regarding Hoosier R100 slick pressures hot/cold; front/rear?
- Also camber..

Note that I am not running the DOT radial slick which many use, and which have different characteristics from the race slick.

I am running 305x645x18 all around on 10.5 rims (with re-staggered front shock/Watts link setup from Cortex).

Thanks in advance for any replies as I am leaving for the Glen Monday afternoon.

BTW, Anyone had problems with the trans cooler scoop on lowered cars?
 

OLOABoss

AKA OLOABoss
R100 should be no more than 30psi hot. I would start out @ 22psi and bleed as necessary. Also got out easy on 1st couple of laps to build pressure as they will feel floppy until pressure comes up.

Peter
 
I've been running these all season (Continental rebrands). I also talked extensively with Hoosier about it. They recommend running 32-34 hot, starting at 24-26 cold. I start at 26 front and 25 rear and usually land around 33 hot. I drop 1/2 to 1 lb cold on the "outside" tires depending on the rotation of the track (e.g. clockwise) I've been buying them from the GTTrackdays.com guys and they run relatively light (approx 3000 lb) Corvettes. They run the pressures exaclty as Peter has indicated. With our cars being 500-600 lbs heavier, Hoosier is recommending higher pressure for a car of that weight.

Regarding camber, I'm at -3.1. At Road America and BIR it seemed just about right. On tighter tracks I could use a little more.
 
I have the last email from Jeff regarding tire pressures on my work computer. I'll try to remember to post that info tomorrow, but it's essentially what I posted above.
 
344
0
Thanks guys.
This is exactly what I need to get started.

- Any problems with the trans cooler scoop?
I just noticed mine scraping getting off the lift.
..Will be lower still after corner weighted & suspension is dialed in (tomorrow) b/4 hitting the road ;D ;D
Per Cortex, I will be 4.25 ground to rail/front; 4.5 ground to rail/rear

Kooks LT w/off road H going in when I return :D
 
lbp said:
Thanks guys.
This is exactly what I need to get started.

- Any problems with the trans cooler scoop?
I just noticed mine scraping getting off the lift.
..Will be lower still after corner weighted & suspension is dialed in (tomorrow) b/4 hitting the road ;D ;D
Per Cortex, I will be 4.25 ground to rail/front; 4.5 ground to rail/rear

Kooks LT w/off road H going in when I return :D
The Cortex setup sounds pretty serious. Can't wait to hear how it goes. What tune are you getting to go with the Kooks and o/r H-pipe? I really want to do that one but don't want the associated CEL if possible.
 
344
0
cloud9 said:
I've been running these all season (Continental rebrands). I also talked extensively with Hoosier about it. They recommend running 32-34 hot, starting at 24-26 cold. I start at 26 front and 25 rear and usually land around 33 hot. I drop 1/2 to 1 lb cold on the "outside" tires depending on the rotation of the track (e.g. clockwise) I've been buying them from the GTTrackdays.com guys and they run relatively light (approx 3000 lb) Corvettes. They run the pressures exaclty as Peter has indicated. With our cars being 500-600 lbs heavier, Hoosier is recommending higher pressure for a car of that weight.

Regarding camber, I'm at -3.1. At Road America and BIR it seemed just about right. On tighter tracks I could use a little more.

Gary,
What is the ambient temp for 24LB; 26?
Thanks,
Lee.
 
Sorry I didn't ask him that specifically, and haven't noticed a big difference either way. I do get more buildup on the sun side of the car as the day goes on though. I've been starting 26/25 cold anywhere from 70-90 degrees ambient. As long as I air down after fully cooled (1.5hrs between sessions) I usually end up at 32-33 hot.

I might try 1lb less at this next event to see how I like it.
 

OLOABoss

AKA OLOABoss
Gary

R100 Hoosiers are full slicks and bear no relationship to the Hoosier R6 or the Conti. They need to run at lower pressures hot hence the max 30 psi hot. I have run the R100 on the GT2.

Peter
 
OLOABoss said:
Gary

R100 Hoosiers are full slicks and bear no relationship to the Hoosier R6 or the Conti. They need to run at lower pressures hot hence the max 30 psi hot. I have run the R100 on the GT2.

Peter
Peter,

The Conti are slicks. They're used in the Continental Challenge. Continental doesn't actually produce a slick, so they have Hoosier make them for the race.

I'll post up the email I got directly from Hoosier on pressures for the R100 when I get to my office computer tomorrow.

Gary

Here's a pic of the slicks I've been running this year. I'm on my 4th set.

20120314181932439.jpg

By cloud91965 at 2012-03-14
 
I am all over the place on pressures. I got great wear on a set of Nitto NT-05's at 22 cold and 30-31 hot. Then I tried running the Hoosier/Conti's at 35 Hot and corded them bad. Now I run at 38-39 or so up front and I am getting great wear off of them. Just had two tires go 4 days, two at PBIR and two at Sebring, a little more wear in the center but mostly even and better then cording them in a day and a half.

From what I understand the GA teams are running about 26-27 cold and about 40 hot.


Edited to make sense, it's late Im tired and read Peter's post wrongly.
 
cloud9 said:
The Cortex setup sounds pretty serious. Can't wait to hear how it goes. What tune are you getting to go with the Kooks and o/r H-pipe? I really want to do that one but don't want the associated CEL if possible.

Would an 02 spacer or isolator work?
 

OLOABoss

AKA OLOABoss
Gary

Yes you can call the Conti a slick as it does not have the 2 groves as the A6/R6 but it is basically the same tire construction and more of an endurance compound with less overall grip than an R6.

The Hoosier R80/R100 is a full race slick with significantly different construction and compound than the so called DOT slicks. When we ran them in 2009 at the UTCC on the GT2 Jeff Spears from Hoosier was there and confirmed Hoosier website specs of no more than 30psi hot and tread temps with 20 degrees difference inside to out.

Peter
 
OLOABoss said:
Gary

Yes you can call the Conti a slick as it does not have the 2 groves as the A6/R6 but it is basically the same tire construction and more of an endurance compound with less overall grip than an R6.

The Hoosier R80/R100 is a full race slick with significantly different construction and compound than the so called DOT slicks. When we ran them in 2009 at the UTCC on the GT2 Jeff Spears from Hoosier was there and confirmed Hoosier website specs of no more than 30psi hot and tread temps with 20 degrees difference inside to out.

Peter
Ok, I found the emails just for clarification.....I'm sure 30 psi HOT is a good pressure since the GTTrackdays guys run that pressure, but 32-34 is okay too according to this email. I'll try experimenting with a little lower pressures 1lb at a time to see how it works.

"Gary,

The HOT pressures for the R100 seem a bit high. You are welcome to run them closer to 32 – 34 psi HOT.

I am comfortable recommending the 285/645R-18 R100 to be used on a 18 x 9.5 wheel.

Good questions.

Jeff Speer, HRT"

"Gary,
Typical air pressure build within a 20 – 30 minute track session would be 6 – 8 psi. That said, your COLD starting pressure would be 24 – 26 psi.

Using the R6 heat cycling procedure would work well on the R100 as well. We really do not have a Tire Care Tips for our GT slicks, but following some of the same procedures will work well.

Good questions.

Jeff Speer, HRT"
 
344
0
loco pantelonez said:
cloud9 said:
The Cortex setup sounds pretty serious. Can't wait to hear how it goes. What tune are you getting to go with the Kooks and o/r H-pipe? I really want to do that one but don't want the associated CEL if possible.

Would an 02 spacer or isolator work?

The Cortex setup is comprehensive. Plus Ohlins ttx36 rear ttx46 front.
I'll post how the Kooks (& Cortex) changes things, as I did do a bone stock session at NJ Motorsports Park a few weeks ago (except Barton shifter & DynoTech DS).
I was hung up on the cel thing too, but have a catted pipe for the street, which I probably won't use much.
However I also understand that even with the Kooks cats installed you can still throw codes. They also have a "green" cat which is supposedly better in that regard...
 
344
0
Here is some video of the car set up with Cortex & Hoosier R100:

[youtube]http://www.youtube.com/watch?v=SB9a2-3me08&feature=youtu.be[/youtube]
Ran 2:11-12's at the Glen on 7/3.

TP cold front 24; rear 25
Hot 33/34

Thanks for all the tips. It gave me the starting points I needed.
 

OLOABoss

AKA OLOABoss
ibp

Did you do hot tire temps as that is the only way to reliably judge tire pressure and camber settings or did you just say hay it feels good so it must be right. ;)

Peter
 
344
0
OLOABoss said:
ibp

Did you do hot tire temps as that is the only way to reliably judge tire pressure and camber settings or did you just say hay it feels good so it must be right. ;)

Peter

I did some early temps across the tires which varied by about 5 deg., but cannot remember numbers nor did I record since I was still settling pressures.
- What temps do you like to see?
...Camber was 2.20, so offset bolts are needed. Looking for 3.25 - 3.5 neg. deg.
May also lower front/rear by another .25" ea. Current height is 4.5 front, 4.75 rear.
Also maybe stiffer on front sway bar (Eibach), but need to watch the push... (& if so tweak with tire pressures..)
Thanks for posting.
Lee.
 

OLOABoss

AKA OLOABoss
Lee

When we ran the R100 on strut type suspension we found you didn't need huge negative camber but we ran much stiffer springs. Definently should have around 20 degrees minimum difference inside to outside for proper wear and grip. I will say this it was hard to go back to R6 after running the R100. Keep us informed on what camber you finally decide on

Peter
 

TMO Supporting Vendors

Top