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New Wheels for my.....future Boss

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RoadRacer78 said:
There is obviously a point where the sidewalls will get too tall and “flop” over when side loaded but what you are talking about is nowhere near that.

I am a big fan of taller sidewalls (if designed correctly) for roadracing. In the early 2000’s 16.5” rims (opposed to the normal 17” rims) became available to the non factory riders (me) and they were a huge leap in performance. Easily 1-1.5sec/lap. The overall diameter of the tire stayed the same (if not grew) so when you were on the edge of the tire it would spread out more and give a bigger contact patch. They also had the added benefit of conforming to and absorbing surface irregularities that would have a 17” tire chattering across the tops of the bumps. The only downside, and a very small and almost unnoticeable one was that the tire would move around on the rim a bit more and give a slight “loose” feeling. I like riding like that though because I think it gives me more feedback so it didn’t bother me in the least.

I think you should take a shot at the taller tires. In a car I can see them paying huge dividends across ripples, etc. In essence they are adding some “suspension” to the tire. You may find you want to use a touch more rebound damping with them though. Just a touch.

Nice wheels by the way.
Thanks for the feedback. I think I'll try the 275/40/18s. As AZGT also said it will help with the gearing by being closer to the stock diameter than the 35s. I have noticed that "loose" feeling you describe when running Hoosiers at lower pressures. Lap times were better but it felt "weird". After you get used to it, it's not a big deal.
 
cloud9 said:
Do you think I'll need a spacer up front with +45?
Shouldn't need them. I'm running +44mm offset rims with my GT500 Brembo's and your rims have a little more spoke clearance than mine.

cloud9 said:
I have noticed that "loose" feeling you describe when running Hoosiers at lower pressures. Lap times were better but it felt "weird". After you get used to it, it's not a big deal.
Once you drive on them for a while you will begin to expect and love that feeling. Without out it things feel "numb" to me.
 
cloud9 said:
Cool. Sorry, but what model/year Mustang is it? Yours 9.5w x 18 too?
Those are on my 2007 GT but I put 2007 GT500 Brembo's on it (I would like to get "real" ones some day ;)).

Yeah, I'm running 18x9.5's with +44 on the front and 18x10.5's with +56.7mm on the rear (I had to have the rears widened from 9.5").

There Rota DPT's. Not quite as light as those Enkeis


RotaDPT-1.png
 
iDrive said:
Thanks, I'll be fitting 18x11 f/r and I want to make sure and tuck them in as much as possible. I know +40 works and you have +45. I have even heard +55 works in the rear with a spacer up front to clear the shock towers.

Dave
You can’t run 11’s on a S197 unless they are 20’s or you want to modify the part of the frame that the rear bump stops (on the axle) contact. 20x11’s with the PERFECT offset and 315’s fit flush with the fenders and will touch the frame where the bumpstops hit slightly at full droop. My 18x10.5’s with 56.7mm of offset and 295’s kiss the frame just slightly at full droop.

I suppose you could maybe fit some 11’s up front but the tires would contact the frame at full lock.
 
RoadRacer78 said:
iDrive said:
Thanks, I'll be fitting 18x11 f/r and I want to make sure and tuck them in as much as possible. I know +40 works and you have +45. I have even heard +55 works in the rear with a spacer up front to clear the shock towers.

Dave
You can’t run 11’s on a S197 unless they are 20’s or you want to modify the part of the frame that the rear bump stops (on the axle) contact. 20x11’s with the PERFECT offset and 315’s fit flush with the fenders and will touch the frame where the bumpstops hit slightly at full droop. My 18x10.5’s with 56.7mm of offset and 295’s kiss the frame just slightly at full droop.

I suppose you could maybe fit some 11’s up front but the tires would contact the frame at full lock.

I have been running 18 x 10.5 38mm offset Enkeis on the back of my GT500 with a 305/35/18 R888. The tire sits out a tad from the fenders but I haven't had any rubbing.
 
cloud9 said:
I have been running 18 x 10.5 38mm offset Enkeis on the back of my GT500 with a 305/35/18 R888. The tire sits out a tad from the fenders but I haven't had any rubbing.

Wow, really? By any chance have any pics? I'm due for a new set of rubber and the R888's in that size is what I was going for (in the rear). Maybe I can split the difference a bit with some spacers.
 
RoadRacer78 said:
cloud9 said:
I have been running 18 x 10.5 38mm offset Enkeis on the back of my GT500 with a 305/35/18 R888. The tire sits out a tad from the fenders but I haven't had any rubbing.

Wow, really? By any chance have any pics? I'm due for a new set of rubber and the R888's in that size is what I was going for (in the rear). Maybe I can split the difference a bit with some spacers.
Here you go. The top pic actually shows Hoosier R6s rear 295/30/18 front 275/35/18. The bottom two are Toyo R888s rear 305/35/18, front 275/35/18.
 

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cloud9 said:
The bottom two are Toyo R888s rear 305/35/18, front 275/35/18.
That's the combo I'm going with front and rear. I'm suprised you aren't getting any rubbing out of the rears, which is great! I think I'll have my buddy spin out some spacers for my rears that have real tight hub centric rings (I've got the long ARP studs) built in so I can get the tire to sit out a little further.

Thanks for posting up!
 
RoadRacer78 said:
cloud9 said:
The bottom two are Toyo R888s rear 305/35/18, front 275/35/18.
That's the combo I'm going with front and rear. I'm suprised you aren't getting any rubbing out of the rears, which is great! I think I'll have my buddy spin out some spacers for my rears that have real tight hub centric rings (I've got the long ARP studs) built in so I can get the tire to sit out a little further.

Thanks for posting up!
Are you thinking I'd have rubbing on the inside? There's plenty of room inside yet....at least 1/2". I am running a Koni coilover with a Griggs '315 kit' which moves the top of the shock inside the wheel. Shocks are installed upside down with that kit.
 
RoadRacer78 said:
cloud9 said:
The bottom two are Toyo R888s rear 305/35/18, front 275/35/18.
That's the combo I'm going with front and rear. I'm suprised you aren't getting any rubbing out of the rears, which is great! I think I'll have my buddy spin out some spacers for my rears that have real tight hub centric rings (I've got the long ARP studs) built in so I can get the tire to sit out a little further.

Thanks for posting up!
No problem. They do make a 10.5 x 18 with 15mm offset which would push them out further but probably too far?
 
cloud9 said:
Are you thinking I'd have rubbing on the inside? There's plenty of room inside yet....at least 1/2". I am running a Koni coilover with a Griggs '315 kit' which moves the top of the shock inside the wheel. Shocks are installed upside down with that kit.

At full droop (not that I jump the car a lot ;D) I will have a slight rub on one side (inside) because of the panhard bar. It sounds like I can make some spacers/hub centric rings and move the wheels out just a touch though by the looks of your setup and eliminate that. I am still a smidge inside the fenders on my car.

Gotta say I’m more than a little jealous of the Griggs goodies. If I was taking the car to the track much I would have to consider it. After I am done with the Rally Car I think a dedicated track car is in order. Then a call to Griggs. ;)

Thanks again!
 
Gotta say I’m more than a little jealous of the Griggs goodies. If I was taking the car to the track much I would have to consider it. After I am done with the Rally Car I think a dedicated track car is in order. Then a call to Griggs. ;)

Thanks again!
[/quote]
No problem. It is a great system but it's expensive and somewhat noisy. I hope I'm not disappointed in the Fays2 Watts link I bought for the Boss, but I didn't want to pull the finned diff cover off to install a Griggs. My hope is what Ford gave us will be good enough for DE events without replacing the entire suspension with a Griggs setup.

What is your opinion on the "low compressibility" brake lines? I am getting ready to pull the trigger on a set of Goodridge braided steel lines like I have on the GT500.

Also I can't see not putting a set of caster/camber plates on from the get go. I'll daily drive the Boss splitting time with the GT500 so would probably set it up with negative 2 degrees to make street driving workable. I ran probably 8-10k miles on the street last summer without any significant front tire wear on the street tires at -2. If I go to 2.5 or more I'm guessing street driving won't be fun.
 
cloud9 said:
What is your opinion on the "low compressibility" brake lines? I am getting ready to pull the trigger on a set of Goodridge braided steel lines like I have on the GT500.

On a street car I can’t see going out of my way to do it. But for a car that hits the track absolutely go with some lines. I have ridden a few nearly stock bikes at the track and the stock brake lines which are pretty good drive me insane. If feel far more insulated from the front contact patch than I want to be for trail braking….on something that tips over. And car brakes aren’t nearly as forgiving as bike ones are. Bikes are easy to slow down and the rotors stay nice and cool. For a track car good fluid bled every time you go to the track, good pads, air ducts and good lines would be what I would consider a absolute minimum.

I think you mentioned that you are still running your GT500 brakes in your GT500 but with DBA rotors. Anything else to the setup? What are your thoughts on the performance of the package?


cloud9 said:
Also I can't see not putting a set of caster/camber plates on from the get go. I'll daily drive the Boss splitting time with the GT500 so would probably set it up with negative 2 degrees to make street driving workable. I ran probably 8-10k miles on the street last summer without any significant front tire wear on the street tires at -2. If I go to 2.5 or more I'm guessing street driving won't be fun.
I ran my 2007 on the street for 12K miles with no CC plates at all and I set the camber up at -1.8 with zero toe and it worked great. I cave a little cupping on the front edge of the tread blocks on insides of the tires but they are BFG Comp TA KD’s so aren’t exactly the most forgiving tires out there.

I think you underestimate how good you have it though. I think you are going to get the new car to the track and in short order you are going to want it to work like the GT500. If your anything like me, and I’m guessing you are. You will quickly go find the limits of the car no matter its state of “tune”. It would be a lot of work but your BOSS should have your Griggs stuff and you can put the BOSS stuff on the GT500. I’d bet the BOSS will be a lot more fun to drive at the track than the GT500.

Have fun, I’m jealous! ;D
 
RoadRacer78 said:
I think you mentioned that you are still running your GT500 brakes in your GT500 but with DBA rotors. Anything else to the setup? What are your thoughts on the performance of the package?
Brembo LCF600 fluid, brake cooling ducts to the fronts and for the track only DTC 70 & 60 pads. It stops the car, but at 4k lbs it eats pads and rotors and fluid has to be changed at least every other event and definitely at least bled. It's hard on brakes with all that weight and I do push the car. I'm going to just go ahead and order the lines for the Boss so I'll be running the same setup as I had with the GT500 but with 400 lbs less on the nose of the car, which in and of itself will make it easier to brake.

I ran my 2007 on the street for 12K miles with no CC plates at all and I set the camber up at -1.8 with zero toe and it worked great.

I think you underestimate how good you have it though. I think you are going to get the new car to the track and in short order you are going to want it to work like the GT500. If your anything like me, and I’m guessing you are. You will quickly go find the limits of the car no matter its state of “tune”. It would be a lot of work but your BOSS should have your Griggs stuff and you can put the BOSS stuff on the GT500. I’d bet the BOSS will be a lot more fun to drive at the track than the GT500.
If I can get -1.8 without c/c plates, I'll be happy to start there. I was only running 2 deg in the GT500. Good to know on the swap of the Griggs. I'm afraid you might be right, but I'm at least holding out hope that I won't have to go to that extreme of swapping the two suspensions. It would cost a fair amount and then there will the requiesite "issues" getting it all dialed in. Yea I'm counting on the Boss being more fun to drive on the road course or I wouldn't be going this route. Thanks for all the advice!
 
BossJockey said:
Gary,
Did you buy tires for the rims? Have you test fit them yet? Pics?
I had a set of Nitto NT01 275/40/18s drop shipped to the dealer Friday and they got them mounted up Saturday on the Enkeis. I'm dropping it off on Monday to put it on the alignment rack and see how much neg camber we can get out of the factory setup. Then we'll test fit to make sure we're OK. We already test fit them on the GM's 5.0 and were OK, so am assuming they'll clear on the Boss. I also have a set of 18 x 9.5s with 275/35/18 R888s and 18 x 10.5s with 305/35/18 R888s from the GT500 that I'll test fit as well. I'll take some pics when I get them home....hopefully tomorrow night depending on how the day goes.
 

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