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I am tired of the rear end

You just can not put the power down early and confidently, period.
In addition to getting a stickier rubber, my main focus will be the rear end traction and here is my plan:

1) Rear LCA with brackets
2) Watts Link
3) Torque arm, yes even the heavy expensive unpopular torque arm.

My approach is unusual, because people will say get better shocks/springs...etc
I want to keep the stock springs/shocks for now.

I should admit, I was spoiled by my previous car, Subaru STI, where in worst case scenario, it would understeer only and you just had to lift off the throttle.

I never had such a powerful RWD car, may be this is a common trait of powerful RWD ( M3, SLS, Vipers, Porsches..etc)...may be.
Regardless, I still think the Boss rear end is not planted and I understand the live axle has a lot to do with this and trust me I do not deal with the throttle as on/off switch, I baby it. :)

I need some serious advice, because the above mods will cost me at least $2500.

Thanks
 
Some think the live axle is better at putting the power down vs. IRS. Where the live axle falls down is on rough terrain. Anyway I was discussing this very topic with Filip the owner of CorteX this afternoon and his suggestion was exactly what you're doing, install a Watts link and torque arm.
 
NFSBOSS said:
Some think the live axle is better at putting the power down vs. IRS. Where the live axle falls down is on rough terrain. Anyway I was discussing this very topic with Filip the owner of CorteX this afternoon and his suggestion was exactly what you're doing, install a Watts link and torque arm.

But see, here is the problem, you speak with Fillip Trojanek and Bruce Griggs, they prescribed the recipe mentioned above then you talk with Sam Strano and Terry fair and they don't believe in the torque arm claimed advantages.
I might pull the trigger and lose the $2500+ :D
 
After talking to Sam Strano, I have gone with the watts link and am really happy with "putting the power down". I won't be looking to change anything soon. From my experience I have gained the best traction from the following (in order of results):
1. Sticky tires, running 305's ATM.
2. Watts Link.
3. Steeda Boss Springs( I believe very similiar to P springs).
4. Slightly soft settings on the rear dampers.

I hope this helps....
 
Grant 302 said:
Are you going to try just the tires first? Or is your plan to get all that done and see if it works for you?

Honestly I was going to try the suspension first, I know it is not the usual way, but I really want to see if my mods will make a noticeable difference while still on the stock tires. I also realize the stickier tires are the best mod you can start with, but I do not want to confound the results with them.
 
+1 for Stickier Tires. You can spend a ton of money on suspension, but your best bang for your buck will be tires. In my case a driver mod should be considered as well! :eek:
 
I have the Griggs torque arm, coilovers and Watts link on my GT500 and the FRPP handling pack, FRPP LCAs and relo brackets along with Whiteline Watts link and Steeda UCA on my Boss. The GT500 rear end bite is noticeably better, but I have $2k more invested in it. Last fall I went to a 315 R6 out back on the Boss and the rear end bite was TRANSFORMED. I literally dropped 2.7 seconds on a 95 second track that I've run 1000 laps on previously which makes the Boss that much faster than the GT500. I'm not making any more suspension changes and instead just spending my money on tires. I was previously running 305 555RIIs, R888s and Conti GT-I slicks. The R6 in the 315 was that much better.

I guess my point is +1 on better tires.
 
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+1 on the tires, though that being said...the M3 will have much more mid corner grip than the mustang does :)
It's just a tradeoff we have with the lack of dynamic camber in the rear end. That being said, the M3 also understeers substantially more (stock to stock).

Our car likes to rotate, so you can still feed the throttle in earlier...just anticipate the rotation. That being said, something that will yield more side bite is lowering the rear roll center. It decreases the stiffness of the rear from a lateral roll perspective and will give you more mid corner bite. Why not consider the kenny brown roll center relocation panhard rod? Cheaper than a watts link...

If we're talking changing suspension bits, I would start there... and then move onto removing any bind from the rear end to address the problem you're speaking of.

I dont think the Steeda Boss springs will help you at all for this problem. The stiffer front will give you much better turn-in response for corner entry...but the stiffer rear PLUS reduced rear roll couple is only going to make your grip situation worse.
 
TMSBOSS said:
Gary

Which wheel and off set are you running with the 315 R6 Hoosiers?
I have two sets of Enkei PF01s in 18 x 9.5 +35mm offset (front) and 18 x 10.5 +38mm offset (rear). The 18 x 10.5 +47mm offset rear would PROBABLY work and tuck the wheel inside more but I haven't tried it. You would lose some "widening" of the track though so rear grip may diminish somewhat. For reference I'm running a 295/30/18 up front with a 1/8" spacer.

I should also add to my comments on the torque arm. The Griggs torque arm doesn't allow pinion angle adjustment (unless you hog out holes and shim etc) so I had to ditch my one-piece drive shaft and go to a 2-piece aluminum/chromoly to eliminate significant driveshaft vibration. I really don't want to deal with that on the Boss so that's another reason I'm not going that route and staying with the FRPP parts. I have it all working well with this tire setup now.
 

Grant 302

basic and well known psychic
further said:
Tires and relo brackets alone will be the best bang for the buck.

That's what I'm getting at...especially after reading Gary's summary about spending money on tires.

13Boss#3328 said:
Honestly I was going to try the suspension first, I know it is not the usual way, but I really want to see if my mods will make a noticeable difference while still on the stock tires. I also realize the stickier tires are the best mod you can start with, but I do not want to confound the results with them.

...but I see some logic in doing just the suspension mods first. Seems a little academic when others have already gone this route and still need good tires.
 
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I'm not going to talk out of school but why don't you guys call Joe at Phoenix and ask him what we're running in the GS car. It's severely rule limited but that car pulls off the corner as well as anyone else. Several people this past weekend at Daytona commented on it. I know the $10k penskes are a little pricey but you could probably copy the rest of it.
 
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blacksheep-1 said:
I'm not going to talk out of school but why don't you guys call Joe at Phoenix and ask him what we're running in the GS car. It's severely rule limited but that car pulls off the corner as well as anyone else. Several people this past weekend at Daytona commented on it. I know the $10k penskes are a little pricey but you could probably copy the rest of it.

Someone please do this and report back :D
 

Mad Hatter

Gotta go Faster
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Santiago, Chile
I saw that in the 2012 lightening lap/CarandDriver write up of the Boss LS, they commented that the rear would not come loose.

"If we were looking for faults, we’d say that the rear end has too much grip"

Is that just due to the fast track at VIR, the Corsa tires, or not enough throttle from the drivers?? I have the regular Boss.
I did do a drivers class recently on some Audis and was surprised how dead the S5 and TTrs felt after the Boss. Was very hard to get the tail out unless under late breaking.
 
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Just confirming what I see:

1) No LCA Relos
2) Stock roll center
3) Smaller rear sway bar
4) Panhard rod

I see nothing special! Soooooooooooooooooooooo I guess blacksheep-1 is saying tires are the solution? :D

EDIT: I wonder what the UCA setup is.
 
Re: Relos

Re: Relos

I have posted before about my observation that many of the WC cars I see do not use Relos, or they have them installed, but use the stock location (dead weight). I went to a WC tire test two weeks ago and there were four cars, including a '14 test mule (had a Watts link!). I stuck my head under three of the cars and none of them were using Relos or their adjustment potential.

So, I sent a quick IM to the man (THE man) and lo, a message was sent down from on high. The reply might seem obvious, but it is important to understand the critical (or not so much) nature of Relos. This is the full exchange:

JIMMY:
Hi [REDACTED]. It was great to hang-out with you and the Capaldi team the other day. Always a treat for me. However, distracted by the huge plates of meat that were paraded in front of us, I kept forgetting to ask a question. Even if equipped with LCA relo brackets, all of the cars were set to the stock location. Is there an easy way for you to explain the benefit of this? I think there is an assumption in forum-land that lowered cars should automatically be using the adjustment points. Maybe not?

FORD RACING ENGINEER:
Jimmy good to see you as well. The arm points are just like other adjustments and are changed based on track and weather conditions.

That's it. They are just another adjustment point. Not critical, often superfluous, and probably more confusing/confounding than helpful. I'm suggesting that they should be tested like anything else. Don't set and forget them. Don't use them if they aren't helping. But I am encouraging experimentation. They are cheap, after all. Hope this helps.
 

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