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Going Square, what is needed?

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Fabman

Dances with Racecars
6,519
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca

Fabman

Dances with Racecars
6,519
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Yep. I like the Blowfish hooks better.
 

Fabman

Dances with Racecars
6,519
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Well whatever he likes, if it needs welding, I'm there.
 
167
218
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Finally got new tires on my 18x10 wheels, went with NT01s 275/40 all around.
Also switched to a 23mm RSB and it definitely makes a big difference in cornering.
The first thing that I noticed was a little more understeer, especially in tight, slow corners, but part of that could also be the perception of steering response delay going from 35 AR tires to 40 AR tires.
More importantly, you can definitely get back on the power harder/earlier without worrying about going sideways as much. The car now feels like it is standing up a bit and straightening out while powering out of a corner rather than staying level and the LSD turning the car (fun but sometimes too much).
I have only done the first heat cycle on the new setup so I wasn't driving at the very limit but I like the changes and don't think I would want to go with a smaller RSB since I am on stock suspension.
Another interesting note, I swapped my staggered setup (RE11s 265/35R19 front 285/35R19 rear on OE wheels) back on to see how the smaller RSB felt with that setup and it didn't seem to understeer as much as I expected. That's good new since I don't feel like I have to swap sway bars between track and street setup.
I will report back with more impressions after my track day at MRLS this weekend!
 
Thanks for this post. I am going square as well, but am still waiting for my 18x11 wheels to be delivered. Have a 23 mm RSB ready to install, but the FRPP rep with some knowledge of the Boss suggested that I run with the stock sway bar before switching to the smaller bar. Any thoughts on this setup? Were you running the stock bar with a square setup before switching to the 23 mm? Oh yeah, installed the T springs this winter. Let us know how your next track event goes. Thanks again.
 

Grant 302

basic and well known psychic
Also switched to a 23mm RSB and it definitely makes a big difference in cornering.
The first thing that I noticed was a little more understeer, especially in tight, slow corners, but part of that could also be the perception of steering response delay going from 35 AR tires to 40 AR tires.
Thanks for sharing your experience with the 23mm bar.

However, with a stock Boss, it can be as simple as changing the rear bar to a 24mm GT bar or any other smaller rear bar up to removing it completely.

I've long suspected that the 24mm GT bar would come closest to neutral balance when used square with Boss and most of the OEM spring sets. The spring rates and ratios front to rear between the Boss and GT are relatively close. And if it doesn't quite balance perfectly, it might be just a bit loose, and what some drivers would be looking for.
 
167
218
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Thanks for this post. I am going square as well, but am still waiting for my 18x11 wheels to be delivered. Have a 23 mm RSB ready to install, but the FRPP rep with some knowledge of the Boss suggested that I run with the stock sway bar before switching to the smaller bar. Any thoughts on this setup? Were you running the stock bar with a square setup before switching to the 23 mm? Oh yeah, installed the T springs this winter. Let us know how your next track event goes. Thanks again.

I agree, try it out with the stock sway bar first and see if that fits your style, just be careful trail braking and on corner exit. I did leave the stock bar on at first with the square setup and it is definitely more eager to rotate, which can be good or bad depending on your driving style and the type of driving you do. I wanted to be able to put the power down better coming out of corners and the smaller RSB will definitely allow that. With stiffer springs I am guessing you will want a smaller bar, but you could also play with the damping as well.

I've long suspected that the 24mm GT bar would come closest to neutral balance when used square with Boss and most of the OEM spring sets. The spring rates and ratios front to rear between the Boss and GT are relatively close. And if it doesn't quite balance perfectly, it might be just a bit loose, and what some drivers would be looking for.

Based on my early experience so far with the 23mm bar that sounds right, so depending on how the balance feels on the track I might look into getting a 24mm bar, although the 23mm bar has less understeer on the street than I expected so it might be perfect for the track.
 
Gentlemen, hope your race season is gearing up and going well. My Apex 18x11" ET52 Satin Black wheels finally arrived and I've wrapped them with NT01 305x35x18. Looks awesome and can't wait to get them on the track. I have installed new Ford Racing hubs with extended studs with 25 mm spacers from OPM. Dampers are stock but have the Boss T lowering springs. 2 degrees negative camber. From what I can tell, the front fitment looks ok. However, the rear tires have significant contact with the inside wheel well. Do you recommend rear spacers (size) and extended studs? Anything else I should know about this fitment? I do have a 22 mm RSB to install, but will run with the stock Boss RSB, then switch during test & tune day. Thanks for any advice offered.
 
Hmmm, I'm surprised the rear tires rub on the inside. Spacers should help but maybe someone else has more intel on why they are rubbing.

Although I never did run square on my Boss going square on the stock suspension will cause oversteer. Almost everyone that runs a square setup on a stock Boss has switched to a smaller RSB and you might want to consider doing that before you hit the track. I think others are running a smaller RSB than the 22mm.
 
Any 2012 Boss owners with fitment experience running Apex 18x11" ET52 wheels with NT01 305x35 out there? Have stock dampers, Boss T lowering springs, MM CC plates, 2 degrees negative camber.
 
167
218
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Any 2012 Boss owners with fitment experience running Apex 18x11" ET52 wheels with NT01 305x35 out there? Have stock dampers, Boss T lowering springs, MM CC plates, 2 degrees negative camber.
I'm only running 18x10 square with 275 NT01s at stock ride height so I can't help with the rubbing issue, but FYI I am really enjoying the balance with 23mm sway bar for the track; 22 should be nicely balanced as well. I agree you should try stock bar first, at least on the street (carefully, don't go full throttle exiting a corner or trail brake too hard), to really feel and understand the change, but you will want the smaller sway bar for the track. Are you running a different tire/wheel setup for the street?
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Where, exactly, are you getting rear tire rubbing? Both sides? Is your PHB the OE piece? Are the tires distorting laterally that much?

I'm having quite a bit of difficulty imagining why you're getting rubbing when I'd have half an inch of clearance with the same tires and wheels as yours.


Norm
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
My Apex 18x11 wheels are waiting for shipping from Miami. Can't wait!! Some what surprised to hear that they are rubbing in the rear....... Sounds like a non ajustable panhard problem as mentioned above??

I ran 305/35-18 Nittos on Drifts before and only had problems with rubbing on brake ducts up front.
 
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Yes, I do have an adjustable BMR PHB.Received some good advice from Apex today. The bump stop bracket may be in the way, but only when the axle is unloaded. Use a jack(s) to load the axle, then mount the wheels. Optionally, the bracket can be removed, its spot welded in place, and relocated. A kit exists for relocation. Vorshlag Racing talks about removing this piece in a Utube video. Of course, small spacers can be inserted. What size spacer works well for the fronts with stock dampers? I have a 25 mm so clearance is not an issue, but the tire juts out at least an inch from the fender.
 
I'm only running 18x10 square with 275 NT01s at stock ride height so I can't help with the rubbing issue, but FYI I am really enjoying the balance with 23mm sway bar for the track; 22 should be nicely balanced as well. I agree you should try stock bar first, at least on the street (carefully, don't go full throttle exiting a corner or trail brake too hard), to really feel and understand the change, but you will want the smaller sway bar for the track. Are you running a different tire/wheel setup for the street?
Thanks for the feedback on the RSB. For street, I have stock wheels / tire sizes, Michelin PSS.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Yes, I do have an adjustable BMR PHB.Received some good advice from Apex today. The bump stop bracket may be in the way, but only when the axle is unloaded. Use a jack(s) to load the axle, then mount the wheels. Optionally, the bracket can be removed, its spot welded in place, and relocated. A kit exists for relocation. Vorshlag Racing talks about removing this piece in a Utube video. Of course, small spacers can be inserted. What size spacer works well for the fronts with stock dampers? I have a 25 mm so clearance is not an issue, but the tire juts out at least an inch from the fender.
I'm going to suggest cutting only some of the bracket away. Leave the flat part that the b/s contacts in place so you don't give up all b/s functionality.

Rear bumpstop bracket mod picture 1.jpgRear bumpstop bracket mod picture 2.jpg


You shouldn't need a spacer anywhere near 25 mm thick up front with +52 offset wheels unless you're gaining a huge amount of negative camber with camber bolts (very much preferably Ford's own). 2 or 3 mm clearance to the strut is all you need as long as your wheel flanges are straight and the wheel isn't wobbling for some other reason. FWIW, your NT01's on my wheels would need about a 1/4" thick spacer, and the sidewall would be pushed out another 1/4" due to the difference in actual dimensions as tabulated by Michelin and Nitto. I'm at -1.9° camber, all at the strut tops.


Norm
 
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