Spring Rates

[BlackMamba3]

Let's get one single thread going on this subject. More leaning towards what's better for certain types of driving, personal preference, etc.

Is it better to have stiffer springs up front or in the rear and why? For me, I'm a street/road race/autocross guy. Also, I'm a fan of coilovers vs. struts/shocks and springs.

Chime in with thoughts, experience, suggestions, etc.

Thanks

 

[torridgoat05]

im subscribing.. looking for a nice spring rate for the drag strip without messing up the weight transfer too much

 

[bucolic]

Reviving an old thread...

I'd like to see a sticky with more info like this.

I'm still debating on keeping my FRPP K springs or going with something more aggressive (more firm) like Steeda Sports.

I enjoy very responsive handling and while I know the GT isn't an Evo (my old car), I'd like it to be as 'sporty' as possible without going to full coilovers.

 

[TheVikingRL]

Subscribing

 

[Big Ben]

All I can say is Steeda ultra lights are an amazing compromise. Good drop, amazing ride, not too stiff for transfer and handles much better than stock.

 

[fordrevhead]

subscribing as well. I can drift the car around nice and controlled but too much tail dive shifting and nose dive braking. It's a bit erratic on an otherwise surprisingly refined ride. I dont mind a little drop but dont want too much and I dont want it to ride like my 3/4 ton Dodge either as the roads around here arent that great.

 

[TheVikingRL]

Posted this on some of the other sites recently. Front is about 1/2" lower than stock and the rear is less from what I hear. Not saying there aren't better options for some but for those interested you can't beat the price.

Front: CR3Z-5310-B, $21.59 each
Rear: CR3Z-5560-B, $19.94 each
http://www.fordpartsgiant.com/parts/...3z-5310-b.html
http://www.fordpartsgiant.com/parts/...3z-5560-b.html

Comes out to under $100 with shipping. From what I've heard I suspect they may frequently run out of stock but can't tell from the fordpartsgiant website.

 

[BlackMamba3]

Reviving my old thread. Let's get it going again.

For me personally, as said above, I'm a heavy modified street/club racing kinda guy so my choice is coilovers. I'm actually waiting on an email back from JRZ to see if they've got anything in the works for the 2011+ GT's. Wanting to go with some triple adjustables with piggyback resevoirs. As for spring rates, I'll probably need something in the 500-600lb range up front and between 300-400lb in the rear.

 

[burke985]

Getting my setup put on when i go home which includes steeda sports etc.etc. so ill find out first hand then

 

[seank]

Reviving an old thread...

I'd like to see a sticky with more info like this.

Good luck. Stickies don't seem to happen around here. They are requested on multiple topics filled with information that would help everyone and cut down on redundant threads. Yet they never get stuck to the top of the list.

A reference to start, Ford factory suspension:

Base Gt: Spring(F) = 21.5 N/mm, Spring (R) = 27.33 N/mm, Sway Bar (F) = 34mm, Sway Bar (R) = 20mm

Brembo Pkg: Spring(F) = 23 N/mm, Spring (R) = 29.2 N/mm, Sway Bar (F) = 35mm, Sway Bar (R) = 22mm


Boss: Spring(F) = 26 N/mm, Spring (R) = 32.5 N/mm, Sway Bar (F) = 35mm, Sway Bar (R) = 25mm


Boss LS: Spring(F) = 24 N/mm, Spring (R) = 33.5 N/mm, Sway Bar (F) = 35mm, Sway Bar (R) = 26mm

Comments on the Boss LS setup from, Kevin Groot, lead chassis engineer.

"The Laguna tune is all about handling the massive rear tire, also, because it has a more aggressive [tire] compound, the Laguna has a little more understeer margin. That's because the tires come up to little bit different temps and you have to manage it a little bit better. If you were to make the Laguna as balanced as the base car, there'd potentially be times where novices would be in trouble. We don't want to do that, so we got a little bit more (understeer) margin in that car."

Then check out this thread. Vorshlag has done lots of testing with springs. They ended up going stiffer up front to combat dive and softer in the rear to help with traction on corner exit.
Vorshlag 2011 Mustang GT 5.0 - auto-x/track build (STX?)

 

[modernbeat]

...Then check out this thread. Vorshlag has done lots of testing with springs. They ended up going stiffer up front to combat dive and softer in the rear to help with traction on corner exit.
Vorshlag 2011 Mustang GT 5.0 - auto-x/track build (STX?)

And we also run a square setup. Staggered setups are engineered to understeer - as you quoted by the Ford engineer. That's the FIRST thing we recommend to new BOSS owners - get a set of 18x10 wheels and ditch the 19 inch staggered wheels.