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Going Square, what is needed?

Wingrider said:
…and then there are those who run SPEC mustang and PWC that remove the RSB.

Go figure.

I hope there is no confusion here.

The people who run spec mustang or high sprung coilovers, they have way high of a spring rate that can compensate for the loss of rear sway bar.

Rule of thumb when it comes to the rear mustang suspension:
High spring rate ===> small sway bar or sometimes no sway bar
Stock spring rate and square setup===> smaller than 25mm rsb (stock).

And my above post was describing testing the theory of what rsb size would give the best results for me. Best results will be faster lap times and more balanced car.
 

Grant 302

basic and well known psychic
13Boss said:
I hope there is no confusion here.

The people who run spec mustang or high sprung coilovers, they have way high of a spring rate that can compensate for the loss of rear sway bar.

Rule of thumb when it comes to the rear mustang suspension:
High spring rate ===> small sway bar or sometimes no sway bar
Stock spring rate and square setup===> smaller than 25mm rsb (stock).

And my above post was describing testing the theory of what rsb size would give the best results for me. Best results will be faster lap times and more balanced car.

Grant 302 said:
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.

Hrm...that sounds familiar... ;)

I'm glad your empirical data supports my swag. :)
 
Finally I got to try the 22mm rear sway bar without interruptions from the limp mode!
Yesterday I had a HPDE with Porsche club at Waterford hills raceway, what balanced setup! Way more balanced than the 20mm RSB.

I strongly recommend 22mm rsb with otherwise stock car and square setup.

Having said that, I will try 23mm rsb someday just for the fun of experimentation. Although I am very happy with the car at its current state.

22mm and 23mm rsb were given to me by @twistedneck, Jeff thanks again.
 
167
217
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Finally I got to try the 22mm rear sway bar without interruptions from the limp mode!
Yesterday I had a HPDE with Porsche club at Waterford hills raceway, what balanced setup! Way more balanced than the 20mm RSB.

I strongly recommend 22mm rsb with otherwise stock car and square setup.

Having said that, I will try 23mm rsb someday just for the fun of experimentation. Although I am very happy with the car at its current state.

22mm and 23mm rsb were given to me by @twistedneck, Jeff thanks again.

I know this is an old thread but I was hoping to gain additional insight for my transition to square setup (18x10 F14s on 285/35 R888s for now) on stock Boss suspension.

13Boss- did you end up trying out the 23mm rsb, and did you like it?

I am not a fan of understeer which is one of my reasons for going with the square setup, so I don't want to add slow speed understeer back in by going with an RSB that is too soft. For that reason I was thinking of going with a stiffer/adjustable front ARB instead of softer in the rear, but a 22, 23, or 24mm RSB might be a good, cheap, intermediate step while I get used to the new setup.
 
Changing the RSB is an inexpensive way to test this out. Going stiffer up front also works I guess it just depends on what your goals are. If you're driving it a lot on the street a softer rear bar might be a better option. Have you run the R888's before? Many don't like them on the S197 cars. Also look at the NT01's.
 
167
217
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Changing the RSB is an inexpensive way to test this out. Going stiffer up front also works I guess it just depends on what your goals are. If you're driving it a lot on the street a softer rear bar might be a better option. Have you run the R888's before? Many don't like them on the S197 cars. Also look at the NT01's.

I appreciate the advice. I'm going to start experimenting with the square setup on the street to see what I think about sway bars. Obviously it's not the same as driving on the track but it should give me an idea of if I feel like the car is too tail happy. I have only one quick test run in on the tires; man they're loud but they seem to have good grip. Got them basically for free with the wheels so I won't be upset if I don't love them. I'll definitely check out the NT01s when they wear out. I'm currently running RE-11s which I love but I think may have heat cycled too many times since I've mostly just done canyon/mountain runs that heat up the tires but don't cause a lot of wear since I'm not driving at 10/10ths on the street. They still have decent grip but seem to be greasier at high temps than they used to.
 
5,656
6,740
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Changing the RSB is an inexpensive way to test this out. Going stiffer up front also works I guess it just depends on what your goals are. If you're driving it a lot on the street a softer rear bar might be a better option. Have you run the R888's before? Many don't like them on the S197 cars. Also look at the NT01's.
I'm hearing an awful lot of praise for Federals from the track day crowd and TKM Motorsports here lately. Optima star Mike Maier is also a huge fan. I have no direct experience with them myself, but thought I'd throw that out there just to confuse everybody if nothing else.

Carry on.
 

Grant 302

basic and well known psychic
I know this is an old thread but I was hoping to gain additional insight for my transition to square setup (18x10 F14s on 285/35 R888s for now) on stock Boss suspension.

13Boss- did you end up trying out the 23mm rsb, and did you like it?

I am not a fan of understeer which is one of my reasons for going with the square setup, so I don't want to add slow speed understeer back in by going with an RSB that is too soft. For that reason I was thinking of going with a stiffer/adjustable front ARB instead of softer in the rear, but a 22, 23, or 24mm RSB might be a good, cheap, intermediate step while I get used to the new setup.

I don't think Rabee got around to trying the 23mm before he sold his Boss. He has it for sale in the classifieds...

Since you like the RE-11s, have you considered the RE-71Rs? They seem to be well regarded for Auto-X
 
167
217
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
I don't think Rabee got around to trying the 23mm before he sold his Boss. He has it for sale in the classifieds...

Since you like the RE-11s, have you considered the RE-71Rs? They seem to be well regarded for Auto-X

Ah that's a bummer. I did consider them, and they are amazing for autox, but after discussing with a Bridgestone engineer he thought the RE-11 would hold up better without getting greasy at the higher temperatures associated with track and hard canyon/mountain drives. Physically the tread has held up amazingly well through a few track days, autocross events, and countless mountain drives, and has tons of tread depth left but I'm afraid I may have put the tires through too many heat cycles. When I decide to get new tires I'm probably going to go with a tire that has more grip and wears faster since I don't care about 200TW for auto-x. The R888 that I got with my wheels will be a good trial.
 

Grant 302

basic and well known psychic
That's interesting. I only have experience with the RE-11s on lighter cars, and they did perform well on track. I would have expected the RE-71Rs to be an improvement. I haven't heard much good for the R888 on track, just for stoplight action.
 
5,656
6,740
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Do they come in steam roller sizes for your Frankenstang?? Or will those be for the others in the stable...

I have no idea....they would be way too hard anyway. I can still light the tires up at will so harder tires would only spin more than they do now. I'm starting to think this whole big motor thing was a bad idea. It creates a lot problems for sure. I've solved most of them but getting this thing to hook up in a straight line while maintaining a good cornering balance has been a real challenge. But I'm not throwing in the towel just yet. I was watching some spoiler cam footage from my last time at Laguna Seca with the 335's and the big wing and I am still leaving 2 wide ass black stripes coming down the Corkscrew. Yeah, down hill. :eek:
It's way better than it was, but I still need to work on that. I refuse to use any kind of traction control so it makes it even harder to accomplish. But if I know me...and I pretty much do, I WILL tame this beast. It may take a while, but I'll get there. I always do. Stay tuned. ;)
 
5,656
6,740
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Something I don’t normally believe in but.........detune?
That IS detuned.
I threw away 50 hp and 100 pounds of torque already...what more do you want? lol.
 
5,656
6,740
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
hey, lose another 50 and you will hardly notice!! Who needs more then 600rwhp!:D
I've given up all I'm going to give.
I watched some video again last night. The car really doesn't look bad at all, it's mostly my frustration of not being able to get on the gas as soon as I'd like to and waiting is pissing me off. Of course, tromping on the throttle yields a predictable response.
Mean while, it's not like it's slow....it's just not as fast as I'd like it to be.
I'll get this thing hooked up yet....I have some ideas.
 
Last edited:

racer47

Still winning after 30+ years
384
473
Exp. Type
W2W Racing
Exp. Level
20+ Years
SE WI
Have you messed with anti-squat yet? There may be gains to be had there. When I got up to about 100% anti-squat I had better forward bite but I added mid corner looseness because my lower control arms pointed up to front too much and it caused roll oversteer. So I leveled the arms (went up a hole on the rear control arm reloc brackets) and will go to a more steeply angled 3rd link. The 2011 bmr upper arm mount has 3 positions, a slightly longer length arm and fits 05 to 09. I plan to do this but have not done it yet.

This https://www.bmrsuspension.com/?page=products&productid=964&superpro=0
and this https://www.bmrsuspension.com/?page=products&productid=1690&superpro=0
and maybe this https://www.bmrsuspension.com/?page=products&productid=781&superpro=0

For reference, I'm at 480 whp, 18x10's and 315 r1s's
 
5,656
6,740
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Have you messed with anti-squat yet? There may be gains to be had there. When I got up to about 100% anti-squat I had better forward bite but I added mid corner looseness because my lower control arms pointed up to front too much and it caused roll oversteer. So I leveled the arms (went up a hole on the rear control arm reloc brackets) and will go to a more steeply angled 3rd link. The 2011 bmr upper arm mount has 3 positions, a slightly longer length arm and fits 05 to 09. I plan to do this but have not done it yet.

This https://www.bmrsuspension.com/?page=products&productid=964&superpro=0
and this https://www.bmrsuspension.com/?page=products&productid=1690&superpro=0
and maybe this https://www.bmrsuspension.com/?page=products&productid=781&superpro=0

For reference, I'm at 480 whp, 18x10's and 315 r1s's
Yup, been there done that.
I'm running a torque arm so the 3rd link stuff doesn't quite apply here.
Reluctantly I have added anti squat/roll steer in an effort to gain forward bite.
It is working, but more needs to be done.
This thing makes a ton of torque down low and I've noticed that when I blow the tires up is when I make the motor grunt so I think keeping the RPM higher (and out of the maximum torque band) is key.
My next move will be softening the rear suspension and raising the rear roll center.
I'll bring a few sets of rear springs to test at the Laguna event coming up.
Stay tuned.
 

racer47

Still winning after 30+ years
384
473
Exp. Type
W2W Racing
Exp. Level
20+ Years
SE WI
why did you go to a torque arm?
 

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