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Going up to 22mm rear sway bar?

After going square tire setup on my stock boss, I downsized the rear sway bar to 20mm and I liked it. However, after learning pushing the car more, I kind of miss the tighter feel of the stock setup with 25mm rear sway, but I realized if I go 25 on square, I will end up oversteering everywhere.

So here is my theory: I am thinking to go to 22mm RSB ( 2011+ V6 rsb) and then add spherical bearings rear LCA, so by doing this, it will regain some of the tightness of the stock and the spherical bushings will ensure planting the rear end and deafening me too ;D.
It is just a theory...what do you guys think?
 

JScheier

Too Hot for the Boss!
What exactly are you trying to accomplish? In other words, what do you mean when you say "I kind of miss the tighter feel of the stock setup with 25mm rear sway"?

Is the car currently pushing (under steer) or generating over steer? Is the issue on corner entry, mid-corner or corner exit? Most use the sway bar size (or adjustments) to dial-in / out a certain behavior.

I had the FRPP spherical arms on my car. The noise was really bad... to the point that I replaced them with the non-spherical arms and sold the spherical arms at a loss. The articulation with the spherical arms was great... but that noise... oiy.
 
I should've been more clear. I think the understeer is more noticeable with the corner entry and mid corner. The stock setup had sharper turn in. Obviously the 20mm rsb helped me put the power down earlier and confidently with the square setup.
 
4,835
5,584
So if I'm reading the right, the car is pushing on corner entry, can you adjust the front shocks on compression to a softer setting? or add a touch more camber.
 
I am currently running the 22mm rear sway bar on my otherwise stock suspension with a square wheel and tire setup (Ford Racing BBS 18x9.5 with 275/40/18 Michelin Pilots)

I've found there are pluses and minuses to using the 22mm rear bar

You can definitely feel considerably more roll in the rear and there are times when the rear feels a little less stable

This takes some getting used to especially on high speed corners and quick transitions which I'm sure you've probably noticed with the 20mm rear bar

My setup understeers perhaps a little bit more than I would like

However, it is also very forgiving and easy to control which I found particularly useful when I ran an unfamiliar track a few days ago

The rear can still be manipulated with some trail braking and more aggressive throttle inputs

I'm certainly glad I tried it and overall it makes the car easier to manage than with the stock 25mm rear bar

Anyhow, I'm going to experiment with the 24mm rear sway bar from the GT next to see how that feels
 

Grant 302

basic and well known psychic
VTBoss302 said:
Anyhow, I'm going to experiment with the 24mm rear sway bar from the GT next to see how that feels

I've suggested this many times... while 1mm may not seem like much of an adjustment, it's big when calculating spring rates.
 
I'm with blacksheep on this one.

If you can alleviate understeer by other means, I'd take that route. Increasing you rear bar may not allow to put the power down as early as before. But you never know!
 
Grant 302 said:
I've suggested this many times... while 1mm may not seem like much of an adjustment, it's big when calculating spring rates.

Dean Martin told me once, with the stock Boss setup and tires ( staggered) a 24mm RSB is a better choice than the stock 25mm.

I think going from 20mm to 22mm will strike a happier medium and may be it will be a decent sweet point!
Don't get me wrong, the 20mm with square setup reminded of my previous car, Subaru STI, you could go almost brutal with the throttle on corner exit, but boy I miss the sharp corner entry and mid corner neutrality.
As stated in my OP, I think that I am now more comfortable with the car and pushing it harder at the tracks, makes me wanting a more balanced and less understeer type of handling, even if that means less corner exit brutality. Then again, that is why we have spherical bushings rear LCA so we can plant the rear end. If you talk to the torque arm guys, they swear by it in term of putting the power down...and obviously the spring rates, shocks...etc but my goal is keep it simple as I think the Boss is a way better car than I am as a driver.
 
blacksheep-1 said:
So if I'm reading the right, the car is pushing on corner entry, can you adjust the front shocks on compression to a softer setting? or add a touch more camber.

Very decent suggestion, the camber might help.
 
If you haven't replaced the LCA's you should do so regardless of what you do with the sway bars. They will make the car feel more planted on turn in with less movement. I have the Ford Racing LCA's with the poly bushings and they were a very noticeable improvment on track.

Aren't you the one that keeps saying don't make changes to the suspension? ;)
 
NFSBOSS said:
If you haven't replaced the LCA's you should do so regardless of what you do with the sway bars. They will make the car feel more planted on turn in with less movement. I have the Ford Racing LCA's with the poly bushings and they were a very noticeable improvment on track.

Aren't you the one that keeps saying don't make changes to the suspension? ;)
Yes I am the one who say do not touch the suspension as the car is a better performer than me as a driver.
The fact that I went to square tire setup led me doing a few change to accommodate and mitigate the inherited oversteer after going to square, so I went with 20mm rsb.
I like the minimalistic approach when it comes to modifying an already great car like the Boss.
Now, if I am Randy Pobst for example, I can quickly outperform the stock car and start looking for more racy setup, but the problem is, I am not and likely will never be Randy Pobst.
 
523
433
NFSBOSS said:
If you haven't replaced the LCA's you should do so regardless of what you do with the sway bars. They will make the car feel more planted on turn in with less movement. I have the Ford Racing LCA's with the poly bushings and they were a very noticeable improvment on track.

Aren't you the one that keeps saying don't make changes to the suspension? ;)


I'm with NFSBoss,
Get LCA's if you drive it on the street stay away form bearings. They are way to loud. The FFRP Boss302R control arms are great. I use them and so do others.
I have a few rear sway bars depending what setup I'm using at the time. When I was running the Roush track pac Coil-overs, the 20/22mm worked great. Stock the Eibach 3way was fine. With Koni's and MM springs, my 18mm works best. These are all with a Eibach front sway bar keep in mind. So if you where look in my garage, I will have a 19,20,22,24 and the Eibach. Yes the tag said it was a 19mm bar. pulled it off my wife's V6 Pony, I put my calipers on it and sure enough it was. who knew?
 

Grant 302

basic and well known psychic
13Boss#3328 said:
Dean Martin told me once, with the stock Boss setup and tires ( staggered) a 24mm RSB is a better choice than the stock 25mm.

I think going from 20mm to 22mm will strike a happier medium and may be it will be a decent sweet point!

Okay, but then why are you bothering to ask if you already think you have the answer?
 

Grant 302

basic and well known psychic
I know my above post is a bit snarky...so let me try to explain a little better why I think the 24mm may be the ticket for your mostly stock setup.

As shown in the data below (which I understand may not be 100% correct), you can see there is a relatively large difference in rate between the 24mm and 25mm bar...57 lbs/in. You can also see that the Strano bar has much 'finer' adjustments of only 23 lbs/in. and 40 lbs./in between settings and 'only' 63 lbs/in. between full stiff and full soft. So even switching to the GT 24mm bar, you are making a move that is nearly the same as going from full stiff to full soft on the Strano bar.

Based on your first post here, I'm sure the 22mm will be a significant move in the right direction for improving the characteristics you aren't liking about the 20mm. But please don't simply dismiss the 24mm as your solution until you've had a chance to try both.

VTBoss302 said:
Some interesting info on rear sway bars I found on Strano's site (not sure if it's accurate):

Comparison vs. Ford OEM:
Strano Performance Parts 8419 1" tubular: 162, 185, 225 lbs/in
Ford 20mm Solid (2005-2010 GT): 96 lbs/in
Ford 22mm Solid (2011+ V-6 standard): 147 lbs/in
Ford 24mm Solid (2011+ 5.0, GT500): 193 lbs/in
Ford 25mm Solid (Boss 302): 250 lbs/in
Ford 26mm Solid (Boss 302 Laguna Seca): 275 lbs/in

Everybody else, please don't get me wrong about the benefits of switching to even smaller bars when you are on aftermarket/stiffer than stock springs. My comments are very specific to the near-stock Boss suspension of the OP.
 
Grant 302 said:
Okay, but then why are you bothering to ask if you already think you have the answer?
His comment was on a staggered setup, not square.

Thanks all for your comments
I will likely try 22mm next year and will report back.
 
4,835
5,584
If you are experiencing push on corner entry I would .
1. lower the front tire pressure, and or bump up the rear. Keep in mind the tire is just another spring (among other things)
2. similar to point 1, soften the front shock on compression and or soften the rear in rebound

Those would be my first "go to adjustments" on just about any suspension change, switching bars is a pretty major step,( especially since I've mentioned in another post) that just by going to nitrogen you could have a massive 6 psi change which will totally change the setup. Stay simple (and in most cases, cheaper).
 
blacksheep-1 said:
If you are experiencing push on corner entry I would .
1. lower the front tire pressure, and or bump up the rear. Keep in mind the tire is just another spring (among other things)
2. similar to point 1, soften the front shock on compression and or soften the rear in rebound

I will consider making those changes before buying anything. KISS approach is almost always the best.
 
It sounds like we are both in similar situations of trying to dial out a bit of understeer without going too far in the other direction

In the end it's all about coming up with a setup that works best for you

Tire pressure and shock adjustments made a difference for me when I was still running the stock 25mm rear bar

However, it wasn't enough which is why I decided to experiment with different rear bars (I bought a 22mm and a 24mm)

They are relatively inexpensive and my dealer gives me employee pricing, as well (I think MSRP is around $90 a bar and I paid a little over $60 each)

Based on first hand experience, I feel confident in telling you that the 22mm will not be too much rear bar for you

I THINK the 24mm bar will end up being the right balance for ME, but I won't know until I get it back to the track next year (we've already had a hard frost around here)
 

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