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S197 Tire Fitment...

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The wheels and stance looks great.
Did you have to modify the rear bump stop to clear the 305/35 series tires?
Also, which FRPP springs do you have?

I did not have to modify the bumps. I did have to glue the rear fender liner to the inside of the wheel well to stop it from contacting the tire ( I just used a small dollop of 3M panel adhesive; about the size of a quarter, and pressed it against the inner tub until it dried). I suppose you could also just cut it to clear as well. I’m trying to leave the car as intact as I can, so in the event I ever want to return it to completely stock, I have that option.
I was worried about the rear bump, but with the 19” I don’t think it’s as much of an issue as it is with 18”ers. The biggest concern was with the 285’s up front. When I picked them up from being mounted, I was thinking “there’s no way these’ll fit”... but I can almost fit my pinky in between the tire and the strut (plenty of room! Lol), so I’m glad for that as well. Haven’t noticed any tram-lining as others have mentioned, either. I haven’t tracked these yet, so we’ll see how they work.

I used all FRPP parts, and the springs were the Boss-specific units. M-5300-T if I remember correct.
 
303
251
Exp. Type
HPDE
Exp. Level
3-5 Years
25 min. to 1½ hrs. from Sonoma (ugh... traffic!)
... glue the rear fender liner to the inside of the wheel well to stop it from contacting the tire ( I just used a small dollop of 3M panel adhesive; about the size of a quarter, and pressed it against the inner tub until it dried). I suppose you could also just cut it to clear as well. I’m trying to leave the car as intact as I can, so in the event I ever want to return it to completely stock, I have that option.

What worked well for me was to use a heat gun to soften the plastic so I could re-mold it a bit. Hold it the form you want it to have while cooling with a hose.
 
I did not have to modify the bumps. I did have to glue the rear fender liner to the inside of the wheel well to stop it from contacting the tire ( I just used a small dollop of 3M panel adhesive; about the size of a quarter, and pressed it against the inner tub until it dried). I suppose you could also just cut it to clear as well. I’m trying to leave the car as intact as I can, so in the event I ever want to return it to completely stock, I have that option.
I was worried about the rear bump, but with the 19” I don’t think it’s as much of an issue as it is with 18”ers. The biggest concern was with the 285’s up front. When I picked them up from being mounted, I was thinking “there’s no way these’ll fit”... but I can almost fit my pinky in between the tire and the strut (plenty of room! Lol), so I’m glad for that as well. Haven’t noticed any tram-lining as others have mentioned, either. I haven’t tracked these yet, so we’ll see how they work.

I used all FRPP parts, and the springs were the Boss-specific units. M-5300-T if I remember correct.

Thanks for the info.

I want to do similar suspension mods. I would like to run the taller FRPP "P" springs.
Looking to see if a 19x11 rim with 295/35/19 will fit on the rear WITH OUT modifying or relocating the bump stop bracket.
I know that Nittos run a bit smaller than either Michelin or Conti's. I would really like to run the PS4S's if I have enough clearance.

My car (a 2013 Boss) is strictly a fun street car.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
I want to do similar suspension mods. I would like to run the taller FRPP "P" springs.
Looking to see if a 19x11 rim with 295/35/19 will fit on the rear WITH OUT modifying or relocating the bump stop bracket.
You can remove the part of the bracket that's used for shipping tie down purposes without losing the OE bumpstop contact pad function. The part you leave in place should be sufficiently rigid and strong without needing any reinforcement.

With 19x11's, you may or may not need to trim the length of the shock boots a bit. I did have to with 285/35's on 18x11's (ET in the mid +50 neighborhood, not the +52 that I think Apex now uses for their wheels)

Rear bumpstop bracket mod picture 1.jpg

Rear bumpstop bracket mod picture 2.jpg


Norm
 
You can remove the part of the bracket that's used for shipping tie down purposes without losing the OE bumpstop contact pad function. The part you leave in place should be sufficiently rigid and strong without needing any reinforcement.

With 19x11's, you may or may not need to trim the length of the shock boots a bit. I did have to with 285/35's on 18x11's (ET in the mid +50 neighborhood, not the +52 that I think Apex now uses for their wheels)

View attachment 14715

View attachment 14716


Norm

Thanks Norm.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,425
8,350
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Blair, Nebraska
Should be no problem at all with only 295s on the rear. There are plenty of folks running 305s with no issues. Welcome to TMO and this is a great place to hang out , get info, and socialize --- even when the Virus is over!
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
As far as section width is concerned, there's hardly any difference at all between 285/35 (MPSS) and a nominal 295/35 when they're both mounted on 11" wide wheels (the "measuring width" isn't the same, so the 285 gets 'stretched' a bit more and both end up at about 300mm). Tread width normally would, which should mainly come into play on the outside. 19" vs 18" obviously takes half an inch of vertical clearance away, and raises the car ride height up by about the same amount.

I made the offsets slightly different because otherwise all the lines essentially fall on top of each other for the at-the-ground plot . . . they're that close.

2953519 vs 2853518 on 11 inch wide wheels.jpg
 
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As far as section width is concerned, there's hardly any difference at all between 285/35 (MPSS) and a nominal 295/35 when they're both mounted on 11" wide wheels (the "measuring width" isn't the same, so the 285 gets 'stretched' a bit more and both end up at about 300mm). Tread width normally would, which should mainly come into play on the outside. 19" vs 18" obviously takes half an inch of vertical clearance away, and raises the car ride height up by about the same amount.

I made the offsets slightly different because otherwise all the lines essentially fall on top of each other for the at-the-ground plot . . . they're that close.

View attachment 14717
Again Norm, thank you for the info.

I can't seem to nail down the tire size/wheel width combo. Just when I think I have it decided, I find new information and it makes me question my decision.

I will give everyone a quick run down about my cars usage.
As of right now, my Boss is bone stock. It is strictly a fun street car/2nd vehicle. Its not my DD. I put roughly 6K miles a year on it. Mainly curvy back roads and spirited driving. Runs up over (local to me) Wachusett Mountain. I have no track experience with the car.

I have contemplated trying my hand at auto-x, but have not done it yet. There are local events that I could easily attend. Finding my way to an actual race track for an HPDE event wouldn't be so convenient, although its on my bucket list.

With that said, maybe 19x10 or 19x11 wheels with 285/35/19 square would be the way to go?
The price difference between the the wheel and tire sizes is minimal. Its the fitment and related expense of hubs, studs and spacers that makes me hesitant. Yet, if ( a big if) I get hooked on auto-x, I would hate to buy these rather expensive components twice. I want to run this new wheel/tire combo both on the street and (if any) track.
 
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Bill Pemberton

0ld Ford Automotive Racing Terror
8,425
8,350
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Be happy to chat about Autocrossing as I live 60 miles from the Solo Nationals site in Lincoln, Ne. and have run through the cones since 1981. I agree that buying the expensive components twice is a major consideration and 285s would be a gross error in my mind as I do not know anyone ( that is competitive) running that size on a Mustang.

Bill Pemberton
402-677-5864
If I do not answer leave a message ( or text ) and who is calling and I will get back with you.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,425
8,350
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Feel free to call me now.........just having a cup of coffee and sitting on my butt like the majority of those in the US of A. No worries not trying to sell you a set or tires, haha.
 
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Again Norm, thank you for the info.

I can't seem to nail down the tire size/wheel width combo. Just when I think I have it decided, I find new information and it makes me question my decision.

I will give everyone a quick run down about my cars usage.
As of right now, my Boss is bone stock. It is strictly a fun street car/2nd vehicle. Its not my DD. I put roughly 6K miles a year on it. Mainly curvy back roads and spirited driving. Runs up over (local to me) Wachusett Mountain. I have no track experience with the car.

I have contemplated trying my hand at auto-x, but have not done it yet. There are local events that I could easily attend. Finding my way to an actual race track for an HPDE event wouldn't be so convenient, although its on my bucket list.

With that said, maybe 19x10 or 19x11 wheels with 285/35/19 square would be the way to go?
The price difference between the the wheel and tire sizes is minimal. Its the fitment and related expense of hubs, studs and spacers that makes me hesitant. Yet, if ( a big if) I get hooked on auto-x, I would hate to buy these rather expensive components twice. I want to run this new wheel/tire combo both on the street and (if any) track.

My car is a fun street toy as well. I carve more mountain roads and twisties than I track it, but performance is still high on my priority list. I chose the sizes I did because I wanted to “max out” what rubber I could while still being streetable, and also earn some “style” points when I’m parking lot-pimping. The 19x10 & 19x11 with the 285 & 305 do that, IMO.

However: if you just want to live with your car, and make the car easiest to live with? Run an 18” or 19” square setup 10” wide with the same tire all around so you can rotate them. It will still handle amazing in the mountains and on backroads, yet give you the luxury and convenience of a streetcar. Not to mention you won’t have to run some crazy camber in the front to get them to fit, or prematurely wear tires because of some crazy camber setting.

If you want to flex on everybody, and have the most capability you can get out of your car? Run an 18” or 19” x 11” wheel all around with a 305 tire. You will have to change some front suspension parts and be “aggressive” with your front camber to get everything to fit, but on a track? The car will be at its most capable, and a force to be reckoned with.

Norm and Bill have taught me a lot about these cars just from reading their posts. They seem to have these cars figured out. They know what the cars like, and what makes them work. I appreciate them as a valuable resource, not to mention Norms tendency to nerd-out about the science of tires, and Bills ever-present comedic supply of Dad jokes.

So, it’s ultimately up to you, Hi RPM. I stressed over wheels and tires for months, so don’t feel alone on that. Whatever you decide, we’ll try to help you be at your best no matter the direction you try to go.
 
My car is a fun street toy as well. I carve more mountain roads and twisties than I track it, but performance is still high on my priority list. I chose the sizes I did because I wanted to “max out” what rubber I could while still being streetable, and also earn some “style” points when I’m parking lot-pimping. The 19x10 & 19x11 with the 285 & 305 do that, IMO.

However: if you just want to live with your car, and make the car easiest to live with? Run an 18” or 19” square setup 10” wide with the same tire all around so you can rotate them. It will still handle amazing in the mountains and on backroads, yet give you the luxury and convenience of a streetcar. Not to mention you won’t have to run some crazy camber in the front to get them to fit, or prematurely wear tires because of some crazy camber setting.

If you want to flex on everybody, and have the most capability you can get out of your car? Run an 18” or 19” x 11” wheel all around with a 305 tire. You will have to change some front suspension parts and be “aggressive” with your front camber to get everything to fit, but on a track? The car will be at its most capable, and a force to be reckoned with.

Norm and Bill have taught me a lot about these cars just from reading their posts. They seem to have these cars figured out. They know what the cars like, and what makes them work. I appreciate them as a valuable resource, not to mention Norms tendency to nerd-out about the science of tires, and Bills ever-present comedic supply of Dad jokes.

So, it’s ultimately up to you, Hi RPM. I stressed over wheels and tires for months, so don’t feel alone on that. Whatever you decide, we’ll try to help you be at your best no matter the direction you try to go.
Daegoba,
My car is, 1st and foremost, a street car. We share the same passion (and by the looks) mainly the same usage for our cars. Thanks for sharing/helping out. Its very much appreciated.

The amount of knowledge on this site is so vast, its almost unbelievable. I am real happy that a member here told me about TMO. Thank you Champale!

Bill, I will take you up on a chat soon. I am supposed to be in the kitchen making breakfast for the family, NOT here on the laptop talking cars. HA!



.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
... not to mention Norms tendency to nerd-out about the science of tires
I'll even take nerd as a compliment. It's part of who I am to make sure that I know I'm getting something for my own 'right reasons' as opposed to being sold something for somebody else's.

I too am old enough to remember hearing "be sure you're right, then go ahead" as uttered by a character in a TV show who had a rather odd sense of headwear . . . the first time around.


Norm
 
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Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Again Norm, thank you for the info.

I can't seem to nail down the tire size/wheel width combo. Just when I think I have it decided, I find new information and it makes me question my decision.

I will give everyone a quick run down about my cars usage.
As of right now, my Boss is bone stock. It is strictly a fun street car/2nd vehicle. Its not my DD. I put roughly 6K miles a year on it. Mainly curvy back roads and spirited driving. Runs up over (local to me) Wachusett Mountain. I have no track experience with the car.

I have contemplated trying my hand at auto-x, but have not done it yet. There are local events that I could easily attend. Finding my way to an actual race track for an HPDE event wouldn't be so convenient, although its on my bucket list.

With that said, maybe 19x10 or 19x11 wheels with 285/35/19 square would be the way to go?
The price difference between the the wheel and tire sizes is minimal. Its the fitment and related expense of hubs, studs and spacers that makes me hesitant. Yet, if ( a big if) I get hooked on auto-x, I would hate to buy these rather expensive components twice. I want to run this new wheel/tire combo both on the street and (if any) track.
Maybe start by deciding if there is a particular tire diameter you want (or need) to stay close to, and list the candidates. Decide whether or not a 'stretched' appearance matters to you, whether the ability to rotate tires from one corner to any other corner matters, and whether you're willing to run spacers and get involved with longer wheel studs up front. Sometimes it's these "side considerations" that end up narrowing the choices down or making the decisions for you.

11" wide wheels do give you room for growth that 10" wides cannot, and actually aren't a bad choice for 285/35's in street duty as long as you're cognizant of the greater potential for curb rash and don't mind the mild stretch. You will get crisper turn-in response (11" is a max-recommended fitment for that tire size), which has considerably more value in street driving than the ultimate lat-g capability that you wouldn't be using there anyway.


Norm
 
Maybe start by deciding if there is a particular tire diameter you want (or need) to stay close to, and list the candidates. Decide whether or not a 'stretched' appearance matters to you, whether the ability to rotate tires from one corner to any other corner matters, and whether you're willing to run spacers and get involved with longer wheel studs up front. Sometimes it's these "side considerations" that end up narrowing the choices down or making the decisions for you.

11" wide wheels do give you room for growth that 10" wides cannot, and actually aren't a bad choice for 285/35's in street duty as long as you're cognizant of the greater potential for curb rash and don't mind the mild stretch. You will get crisper turn-in response (11" is a max-recommended fitment for that tire size), which has considerably more value in street driving than the ultimate lat-g capability that you wouldn't be using there anyway.


Norm

The crisper turn- in response is a good point. I would like to stay with the stock 27-ish inch diameter.
That is why I was hoping that a 295/35/19 would fit/clear on the rear with 19x11 rim.
I am looking to keep the height vs maximum tread width. A 305/30/19 is proven to fit, but its shorter than I would like. I am not sure were/when the actual interference happens. Is it the width or the height?
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,425
8,350
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Some of us love the lower height as it almost feels like dropping a set of higher numerical rear gears in the beast. With 7500 rpms, down low can take awhile to ramp up, the shorter tire helps in my mind. If you decide to Autocross you would need the 305/30/19 ( or similar in an 18 ) to really be competitive. Alot of folks are running that size ( often on a RE71 ) at the Nationals.
 
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I'll even take nerd as a compliment. It's part of who I am to make sure that I know I'm getting something for my own 'right reasons' as opposed to being sold something for somebody else's.

I too am old enough to remember hearing "be sure you're right, then go ahead" as uttered by a character in a TV show who had a rather odd sense of headwear . . . the first time around.


No
The crisper turn- in response is a good point. I would like to stay with the stock 27-ish inch diameter.
That is why I was hoping that a 295/35/19 would fit/clear on the rear with 19x11 rim.
I am looking to keep the height vs maximum tread width. A 305/30/19 is proven to fit, but its shorter than I would like. I am not sure were/when the actual interference happens. Is it the width or the height?

This is why I chose the sizes I did. They are as close to the stock sizes as you can be with the most amount of rubber on the ground. They also “close” the wheel opening gap for a tight fit with no clearance issues.

Admittedly, style and aesthetics weighed heavy on my decision making. The smaller 305/30 does give you a benefit gear wise, but I wasn’t willing to accept the huge gap.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,425
8,350
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Since HiRpm posted he did not want to buy expensive things twice, that was my main motivation to suggest certain tires and rims, and the shorter tires ( than stock diameter) are being used almost across the board by the faster drivers ( track and autocross). Over the years I learned the hard way, getting what I thought was the hot set up and then getting to the events and finding I was behind the times. Many have had this discussion at the Mustang Roundup and once folks see what others are running, the next year the bulk of those competitive spirits, end up with more rubber and a smaller overall diameter. Heck, I am running a 315/30/18 on advice from AZBoss and since he won the Championship in his Class ( NASA AZ Region), I give him credit for helping me do the same in my Region, last year. I would probably have gone with a different tire if completely on my own.

So, my advice is based on Hi not wanting to spend extra bucks if he gets into Autocrossing , and of course he will need to determine his Class also , since he may have to go with a narrower tire or rim size. There are those on here that can help him with that ( DaveW, Autoeux, me, etc. ) but I will constantly remind those of one noted authority , Blacksheep 1, who has often mentioned on the Forum that this machine needs more tire........................that is probably the best source of advice for anyone, considering his record with Phoenix Racing and others!!
 
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Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Admittedly, style and aesthetics weighed heavy on my decision making.
A 305/30/19 is proven to fit, but its shorter than I would like.
No question about it, "style" and "appearance" rank higher with many (probably most) enthusiasts than it should when performance is the clear goal. And I think 'style' and 'appearance' need to be clarified a bit, to mean 'that which fits within generally established/conventional guidelines'.

IOW, as seen by other people and with respect to their preferences.

Dunno, maybe it takes having a nonconformist gene or two to buck convention, to pick what suits your performance goals, and let the appearance fall wherever it may. Or maybe you have to be that much of an engineer about things (things outside of your job if you happen to be an engineer). Though at some point you might just start to associate your Mustang's somewhat different appearance with its somewhat different-from-the-average-Mustang-owner's uses, and come to appreciate it as a sort of 'insider knowledge'. That it looks the way it does for a reason.


Norm
 

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