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Going Square, what is needed?

Hey everyone, could someone provide part numbers for the 18 - 20 mm rear sways?
I have Cortex JRI and have been lifting the rear tire on corner exit (car really just feels tail happy these days). Wanted to try a 20 mm bar. Currently on stock 25 mm boss bar.
Looks like the 2011 v6 bar is 22 mm but with my stiffness I wanted to go to the 20 mm which appears to be an 05-09 GT bar? Will that fit our 2011-2014 cars?
From what I can find the 22 mm is
(CR3Z-5A772-R)

The 05-09 convert bar (18 mm?)
(6R3Z-5A772-B)

05-09 gt coupe (20 mm)
(6R3Z-5A772-A)

The look on the 05-09 is very different, I wouldn't imagine this actually fits our cars?
 
Thanks for the reply / help as always coz.
The 22 mm is about 150 lb / in
I am looking for the 20 because it’s closer to 100 lb. I’d think the Ford perf would be stiffer... I need looser. Looks like others have put the 05-09 bar on?
 
Hey everyone, could someone provide part numbers for the 18 - 20 mm rear sways?
I have Cortex JRI and have been lifting the rear tire on corner exit (car really just feels tail happy these days). Wanted to try a 20 mm bar. Currently on stock 25 mm boss bar.
Looks like the 2011 v6 bar is 22 mm but with my stiffness I wanted to go to the 20 mm which appears to be an 05-09 GT bar? Will that fit our 2011-2014 cars?
From what I can find the 22 mm is
(CR3Z-5A772-R)

The 05-09 convert bar (18 mm?)
(6R3Z-5A772-B)

05-09 gt coupe (20 mm)
(6R3Z-5A772-A)

The look on the 05-09 is very different, I wouldn't imagine this actually fits our cars?
Hey Terry, from my notes, but verify:
22mm rear sway bar 6r3z-5a722-a (-b is 18mm)

hope this helps.
 
Hey Terry, from my notes, but verify:
22mm rear sway bar 6r3z-5a722-a (-b is 18mm)

hope this helps.
Hey there, I think I ran with you at VIR Trackdaze event this past November? I remember the license plate.
That being said, your numbers match what I Found, but that is for the 05-09 car. Do we know if the 05-09 sways fit the 11-14 cars?
 
Hey Terry, we probably did run together ar VIR. It’s my home track. I had the 22mm on the rear for a few track days, so it does fit. I decided to keep the stock 25 mm RSB and go with a larger FSB, the Hellwig 35mm adjustable. Also have MCS coilovers and NT01 305x18 square fitment.
 
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Hey Terry, we probably did run together ar VIR. It’s my home track. I had the 22mm on the rear for a few track days, so it does fit. I decided to keep the stock 25 mm RSB and go with a larger FSB, the Hellwig 35mm adjustable. Also have MCS coilovers and NT01 305x18 square fitment.

22 mm is a 2012 v6 bar. 20 or 18 is the 05-09 bar... that is the one I’m curious about.
I’m running jri Coilovers as well as 305 pirelli squared. We are likely fighting the same problem.
 
So as far as wheels, I want to run a square set up, 285/35R18 use my current rears and two more 9 1/2 rears on the front where am I at ? Spacers? Machined mounting face?
Any info greatly appreciated
 

Grant 302

basic and well known psychic
So as far as wheels, I want to run a square set up, 285/35R18 use my current rears and two more 9 1/2 rears on the front where am I at ? Spacers? Machined mounting face?
Any info greatly appreciated

My understanding is that the rear 9.5" fit on the front. I haven't done the test fit myself, but I remember a story from long ago that one used Boss was spotted at a dealer with the rears mounted up front. I'm pretty sure it's been done and from what I recall the offset should work.
 

Norm Peterson

Corner Barstool Sitter
939
711
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
So as far as wheels, I want to run a square set up, 285/35R18 use my current rears and two more 9 1/2 rears on the front where am I at ? Spacers? Machined mounting face?
Any info greatly appreciated
The 2008-ish GT500 came with 18x9.5 wheels all around (back when Ford wasn't doing the staggered thing), so the wheels will fit up with plenty of strut-side clearance as long as the offset is no more positive than about +45.

It's your 285/35 tires that'll drive the actual offset or thickness of necessary spacers.

I'm pretty sure that people used to run 275/40's on GT500 wheels without issue or a need for spacers, but that last step up to 285/35 is going to make things really tight on the strut side. Very possibly (even likely) less than 1/16" (depending on actual strut dimensions) so you'll at least have to consider using thin spacers. I think that 1/8" or 3mm would be enough, more than 1/4" unlikely (and undesirable unless absolutely necessary for strut clearance under hard cornering). Make sure that you can still get ten full turns of each lug nut, else look into ARP studs (better yet, Ford Racing hubs that already have the ARP studs fitted and gain a fresh set of hub bearings in the process).


Kind of a side note, but the amount of lateral tire distortion in a corner may be somewhat dependent on how wide the wheel is compared to the tire and the width of its "measuring width wheel". Wider (mildly stretched) meaning less distortion and a slightly smaller clearance requirement. Narrower than "measuring" implying that a little more clearance might be needed.


Norm
 
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Grant 302

basic and well known psychic
Norm- there's nowhere near +45 offset on the Boss 9.5". I think +35, maybe +38. There won't be a problem on the inboard side. Even with the 285. My tentative response is for clearance to the front caliper as I have not seen the installation myself. Other 2nd hand reports running the Boss 9.5 square lead me to believe there is no problem there either.
 

Grant 302

basic and well known psychic
I think we need to know more about Skip's 18 x 9.5's.
Agreed. I saw the 'Redkey' avatar and incorrectly assumed the stock Boss 9.5"


I know the 18x9.5 GT500 wheels were +45, at least as sourced through FRPP, and that the Boss/LS ran a 19x9"/19x10" staggered combination.


Norm
Non-LS Bosses have a 9.5" rear.

The LS 19x10 was either +42 or +43, IIRC.
 
22 mm is a 2012 v6 bar. 20 or 18 is the 05-09 bar... that is the one I’m curious about.
I’m running jri Coilovers as well as 305 pirelli squared. We are likely fighting the same problem.
Hey Terry, did you settle on a FSB / RSB combination? What coilover spring rates are you running? Currently, my setup is Hellwig 35 mm full stiff FSB, 22 mm rear, MCS coilovers w 550/250# springs. 305 square Fitment. With the Boss 25 mm RSB, had a bit too much oversteer.
 
Hey Terry, did you settle on a FSB / RSB combination? What coilover spring rates are you running? Currently, my setup is Hellwig 35 mm full stiff FSB, 22 mm rear, MCS coilovers w 550/250# springs. 305 square Fitment. With the Boss 25 mm RSB, had a bit too much oversteer.
Hey man,

I actually wrecked that car and purchased a new one. The new car runs 700#/350# springs with full aero. No strut bar, 35mm front sway and tiny rear sway - both steeda competition adjustable bars. The car rotates!
Sorry can’t help much with your specific situation.
 
167
217
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Also, the tiny rear bar, is a good move, the old PWC/IMSA cars used either the 18mm or no bar in the rear
My last track outing at Big Willow I ran without rear bar for the first time and loved how it felt! Went from almost no rear grip and no ability to put down power, to being able to trail brake properly and put down power coming out of corners. That's with square 18x11/305 A052s, ~-3* camber, 0 toe, Koni yellows, steeda boss comp front spring, and stock rear spring. Was able to fine tune the balance a bit with damper settings, and the overall balance and amount of grip felt so much better!
 

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