Wheel/tire packages for track

[cloud9]

I just signed up to BMO. I purchased by boss May of last year. I am adding the brake cooling kit (right side is in already- what a pain !)and already added the transmission scoop. As with most of you, I want to replace my wheels/tires with a set for the track. Reading all the excellent posts here as well as other websites, I have decided I want to initially run Nitto NT05's 275/40R18 front with Enkei PF01 9.5X18 and 295/35R18 rear with 10.5 X 18. I decided on these based a combination of their price, grip, and wear according to those that have used them. I went with these sizes because they seem to come fairly close to the diameters fo the OEM 19's (so the car is not lowered too much) and based on section width comparison (which I assume provides a good ratio for tread width since tread width is usually not listed).

What I would like some feedback on is this stagger seems to be only about 0.8" (again based on section width ratio and not actual tread width) which might cause some oversteer problems. Any thoughts on this set up? Also, for the Enkei wheels I assume I would go with the 45 mm offset front and rear? Also, any suggestions on other high performance street tires or competition tires that come in these or close to these sizes.

With that set of wheels you want the 35mm offset front and 38mm offset rear. 18 x 10.5 only comes in 38 & 15 mm offsets.

 

[2012YellowBoss]

Going by section width like you stated the setup gives you the same stagger as the factory Pirellis, .82" but with extra rubber since both are .39" wider. This setup has worked very well for me, I do not get oversteer unless it is driver induced. I also run in sport mode so that helps.

The bigger difference is .67" shorter in back and .46" shorter in front. The rear tire height costs 3 MPH in 4Th gear at 7500 RPM's

 

[oldbossman]

Thanks 2012YellowBoss and cloud9 for your input. I guess I just needed some confirmation that this setup was acceptable before I purchase the wheels and tires. The only other question I have is, with the offset you recommend, do the tires extend beyond the fender well?

As a side note, I talked to the rep at performance friction and got the part number for the front and rear pads (01 compound) for the track. He told me that with these pads I can use the stock rotors for now since both compounds (OEM and 01) are close enough that switching the rotors is not necessary. Thus, I will use the stock rotors until they wear out and then maybe get the DBA 5000 for front and 4000 for rear.

 

[cloud9]

Thanks 2012YellowBoss and cloud9 for your input. I guess I just needed some confirmation that this setup was acceptable before I purchase the wheels and tires. The only other question I have is, with the offset you recommend, do the tires extend beyond the fender well?

As a side note, I talked to the rep at performance friction and got the part number for the front and rear pads (01 compound) for the track. He told me that with these pads I can use the stock rotors for now since both compounds (OEM and 01) are close enough that switching the rotors is not necessary. Thus, I will use the stock rotors until they wear out and then maybe get the DBA 5000 for front and 4000 for rear.

The rears are just slightly outside the fender but do not rub even with the suspension fully compressed. I literally have thousands of track miles on this setup between my GT500 and Boss. The fronts are totally inside the fenders. Here's a pic of the GT500 with a 305/35/18.

By cloud91965 at 2011-05-01

 

[lbp]

Thanks 2012YellowBoss and cloud9 for your input. I guess I just needed some confirmation that this setup was acceptable before I purchase the wheels and tires. The only other question I have is, with the offset you recommend, do the tires extend beyond the fender well?

As a side note, I talked to the rep at performance friction and got the part number for the front and rear pads (01 compound) for the track. He told me that with these pads I can use the stock rotors for now since both compounds (OEM and 01) are close enough that switching the rotors is not necessary. Thus, I will use the stock rotors until they wear out and then maybe get the DBA 5000 for front and 4000 for rear.

The rears are just slightly outside the fender but do not rub even with the suspension fully compressed. I literally have thousands of track miles on this setup between my GT500 and Boss. The fronts are totally inside the fenders. Here's a pic of the GT500 with a 305/35/18.

By cloud91965 at 2011-05-01

Nice..
What is the offset of that rear wheel?
Thx.

 

[cloud9]

18" x 10.5" with 38mm offset

 

[lbp]

18" x 10.5" with 38mm offset

OK, & thanks very much.
- Is there any available clearance on the inside sidewall of the tire, or is it all used up?
Thanks again!!

 

[cloud9]

18" x 10.5" with 38mm offset

OK, & thanks very much.
- Is there any available clearance on the inside sidewall of the tire, or is it all used up?
Thanks again!!

About 1 full inch to the bumpstop bracket and rear shock. I saw in the article about the D-Force rims with 315s that the rear sway was the limiting factor, but I believe that was using an after-market adjustable bar. There's lots of room, and I'd have to verify against the factory rear sway bar, but I don't think it sticks out as far as the bumpstop bracket.

 

[lbp]

18" x 10.5" with 38mm offset

OK, & thanks very much.
- Is there any available clearance on the inside sidewall of the tire, or is it all used up?
Thanks again!!

About 1 full inch to the bumpstop bracket and rear shock. I saw in the article about the D-Force rims with 315s that the rear sway was the limiting factor, but I believe that was using an after-market adjustable bar. There's lots of room, and I'd have to verify against the factory rear sway bar, but I don't think it sticks out as far as the bumpstop bracket.

Cool...many thanks.
This is greatly helpful preparatory information.

 

[bulldogracer]

This TSW wheel comes in these sizes
19x9 - 32 offset, 19x9.5-40 offset, 19x10.5-27 offset
Does anyone know what the stock Boss 302 wheel offsets are?
The 302S seems ot be 19x9-47.5 offset, 19x10-47.5 offset
I'm new to tire stagger & offset but the TSW 19x10.5 to me would probably stick outside the fender even with a stock size tire. Great forum just want a nice wheel combo to put the production wheels & tires in storage but maybe have an occasional track day fun with the new ones.

 

[VoodooBoss]

I don't think the 19x10.5 wheels have enough offset to work. I believe the 20" offers more offset options. You can also look at these.

http://www.cjponyparts.com/product.aspx?p=W103&utm_source=google&utm_medium=merchant&utm_campaign=shopping

 

[1-1-12]

I'm thinking of running Hoosier 275/35x18 front and 295/30x18 rear on Enkei PF01 wheels 18x9.5 35mm offset front and 38mm rear. I know some of you are running this combo. I would like some feed back on how this set up works. How long do they Last? What starting
pressures cold/hot? Any problem with the shorter tires? As you can see I'm new to the track and don't want to buy the wrong set up.
Thanks for the help

 

[cloud9]

I'm thinking of running Hoosier 275/35x18 front and 295/30x18 rear on Enkei PF01 wheels 18x9.5 35mm offset front and 38mm rear. I know some of you are running this combo. I would like some feed back on how this set up works. How long do they Last? What starting
pressures cold/hot? Any problem with the shorter tires? As you can see I'm new to the track and don't want to buy the wrong set up.
Thanks for the help

It works great. No issues with the shorter tire and in fact it improves your aero by getting the front splitter closer to the ground. I only get about 2 days out of a set of fronts and 4 days out of the rears. You could PM JBG and get his take. I think he gets twice as many days as I do out of them. I'm pretty sure he had 20+ heat cycles on the set he ran at The Mustang Roundup in Hastings, NE last year.

 

[1-1-12]

Thanks for the help, how about pressures? Is having them heat cycled at time of purchase worth the money?

 

[cloud9]

Thanks for the help, how about pressures? Is having them heat cycled at time of purchase worth the money?

I wear mine out too fast to probably benefit from the heat cycling, but I still usually do it. There's debate on whether the machines can properly heat cycle them or not, but for $15 considering the price of the tires, I'd say it's worth it.

I start at around 31 front and 30 rear and try to get in the high 30s low 40s hot. You'll have to play around with them and if you have a pyrometer, try and check temps right after coming off track. Your goal is to have an even temp on the inside, middle and outside of the tire. More pressure is better on these heavy cars.

 

[1-1-12]

Thanks alot. One more question do you run pressure sensors? If not do they reset when you put the street tires back on?

I guess that's two questions, Thanks.

 

[lbp]

I'm thinking of running Hoosier 275/35x18 front and 295/30x18 rear on Enkei PF01 wheels 18x9.5 35mm offset front and 38mm rear. I know some of you are running this combo. I would like some feed back on how this set up works. How long do they Last? What starting
pressures cold/hot? Any problem with the shorter tires? As you can see I'm new to the track and don't want to buy the wrong set up.
Thanks for the help

Here is the Hoosier link that has information on run in, tire temps/pressures hot/cold settings, alignment, etc.:

http://www.hoosiertire.com/tctR6_A6.pdf

..PS - Couldn't find the link for their slicks FAQ, so this may not be useful, but I'll look again...

 

[cloud9]

I'm thinking of running Hoosier 275/35x18 front and 295/30x18 rear on Enkei PF01 wheels 18x9.5 35mm offset front and 38mm rear. I know some of you are running this combo. I would like some feed back on how this set up works. How long do they Last? What starting
pressures cold/hot? Any problem with the shorter tires? As you can see I'm new to the track and don't want to buy the wrong set up.
Thanks for the help

Here is the Hoosier link that has information on run in, tire temps/pressures hot/cold settings, alignment, etc.:

http://www.hoosiertire.com/tctR6_A6.pdf

Actuallly from Hoosier's site, you want cold presssure of 27-33 and hot pressures in the 38-43 psi range for our heavy cars. I previously went off that PDF you posted until someone pointed out that for road race applications, you want to use this schedule. I changed to the higher pressures last year with excellent results.

http://www.hoosiertire.com/tctips.htm#Tire%20Pressure%20Recommendations%20For%20Competition

 

[cloud9]

Thanks alot. One more question do you run pressure sensors? If not do they reset when you put the street tires back on?

I guess that's two questions, Thanks.

I don't run sensors on my track wheels. I'm almost positive they reset when you put your street wheels back on. I'm only hedging slightly because I have a tool to retrain them, but iirc I haven't needed it on the Boss.

 

[lbp]

I'm thinking of running Hoosier 275/35x18 front and 295/30x18 rear on Enkei PF01 wheels 18x9.5 35mm offset front and 38mm rear. I know some of you are running this combo. I would like some feed back on how this set up works. How long do they Last? What starting
pressures cold/hot? Any problem with the shorter tires? As you can see I'm new to the track and don't want to buy the wrong set up.
Thanks for the help

Here is the Hoosier link that has information on run in, tire temps/pressures hot/cold settings, alignment, etc.:

http://www.hoosiertire.com/tctR6_A6.pdf

Actuallly from Hoosier's site, you want cold presssure of 27-33 and hot pressures in the 38-43 psi range for our heavy cars. I previously went off that PDF you posted until someone pointed out that for road race applications, you want to use this schedule. I changed to the higher pressures last year with excellent results.

http://www.hoosiertire.com/tctips.htm#Tire%20Pressure%20Recommendations%20For%20Competition

I think your link references the same info contained in the pdf link (I now see the "R6" mentioned, too).
I've sent an email to Jeff Speer at Hoosier for some recommendations on the B302 which I will post when received.
My inquiry with him is specifically in regard to running R6 315x30x18 all around
(probably R80 front, R100 rear; as noted elsewhere, square setup requires suspension mods),
- so his reply may not be 100% relevant to the staggered setup most will be running.

Here is his email: [email protected].

Jeff is a very responsive guy and will be sure to answer any questions you ask...