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Debating between a few suspension options

Hi everyone,

Looking to do a budget suspension build on my 2009 GT, I'm debating between a few springs/struts/shocks options:

1. Eibach/Koni STR.T combo

2. BMR handling springs/Koni orange (https://www.americanmuscle.com/bmr-koni-handling-performance-package-level-1-red-0510-gt.html)

3. Steeda Pro-Action and sport springs (https://www.steeda.com/steeda-pro-action-sport-spring-mustang-suspension-package-555-8408.html).

Looking to improve body roll and feedback as much as possible, not looks. I'd rather lower it very mildly.

The car is used mostly as a fun street car with occasional track days about once in a month.

Which one would you choose and why? If you have any other suggestions or products, please post them.

 

Mad Hatter

Gotta go Faster
3,859
2,354
Santiago, Chile
Would be very tempted to go the ford Performance route. You can get it part by part to spread to cost over time. I think the P springs are the best option. Most of the other springs lower the car too much.

here is a edit list from Lmr.com


M-5300-P lowering springs will bring the ride height down about an 1" providing a much improved look & feel.
M-18000-A Shock & Strut Kit,
M-18183-C GT500 style Upper Strut Mounts are already installed on the struts with the springs to allow installation on all 2005-2014 Mustang GT Coupes.
M-5570-A Jounce Bumpers, or bump stops, are included to provide enhanced stability & ride comfort.
M-4264-A Adjustable Panhard Bar is called to duty to re-center the axle in your Mustang once it is lowered.
M-5490-A Front & Rear Anti-Sway Bars are employed to keep you flat through the turns. Plus you get new urethane bushings to go with them!
 
Would be very tempted to go the ford Performance route. You can get it part by part to spread to cost over time. I think the P springs are the best option. Most of the other springs lower the car too much.

here is a edit list from Lmr.com


M-5300-P lowering springs will bring the ride height down about an 1" providing a much improved look & feel.
M-18000-A Shock & Strut Kit,
M-18183-C GT500 style Upper Strut Mounts are already installed on the struts with the springs to allow installation on all 2005-2014 Mustang GT Coupes.
M-5570-A Jounce Bumpers, or bump stops, are included to provide enhanced stability & ride comfort.
M-4264-A Adjustable Panhard Bar is called to duty to re-center the axle in your Mustang once it is lowered.
M-5490-A Front & Rear Anti-Sway Bars are employed to keep you flat through the turns. Plus you get new urethane bushings to go with them!
The thing is FP parts are all back-ordered with no eta at the moment, and I don't plan on waiting month's.
 
584
164
Maybe take a look at Billy's post #75 here:

 
45
28
Exp. Type
Autocross
Exp. Level
Under 3 Years
Colorado Springs
Bump and tagged to see any new responses. Based on how this season went, Im looking at a couple more tweaks for next year. Lowering springs are on the winter project list and a local guy has some "newish" Eibachs for sale about 50% new price. Budget racer..
 
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Dave_W

Cones - not just for ice cream
357
345
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
debating between a few springs/struts/shocks options:
Both options 1 & 2 use Koni STR.T shocks; I'd rather use the Koni Sport (yellow) shocks if going to Konis. The Yellows are rebound-adjustable, so you can adjust them for (moderately) different spring rates, wear, and/or handling. Yellows are still very liveable on the street, as long as you don't go crazy with spring rate.

For springs, I'm of the opinion that you don't want to lower the front much at all, as it leads to worse geometry. Lowering the rear somewhat more than the front is fine, but again don't go to extremes (or you'll end up needing more items to correct things - LCA lower mount extensions, adjustable panhard bar, etc.).

I noticed Vorshlag lists the Eibach Pro-Kit for 05-10 dropping 1.3"F/1.4"R while 11-14 is 1.0"F/1.5"R (in the spring choices for the Bilstein Street kit). Is the factory ride height / front geometry different between those years? I was thinking of staying at 1" or less drop in the front and 1-1.5" in the rear, but maybe the early cars can take more in the front? Personally, I'd probably go with the Ford "P" springs at 1" all around.

You say you want to control body roll more, but none of the options include sway bar(s), which have the most direct affect on body roll. So that's something to think about. Most aftermarket sway bars have multiple holes in the arms to adjust stiffness. The rear Whiteline bar is "reverse" of the factory - the bar center mounts to the axle and the arms / endlinks connect to the body. That can be a good thing (really wide tire clearance) or a bad thing (possible interference with some Watts link setups).

You also say you'll be doing about one track day a month, so 10-12 a year, which is more than enough to include track handling, reliability, and adjustability in your considerations. Which means you really should be looking at camber plates to preserve the ouside shoulders of the front tires; Vorshlag are generally considered the best, but Maximum Motorsports, Ground Control, and Steeda make decent ones as well. I believe GC and Steeda have "street" and "race" versions, with different bearing/bushing types (stiffer for better control but noisier in the race versions).

Depending on how much you like doing track days, you may find yourself wanting to move up to a "coilover" setup after some time. I use air-quotes because the factory McStruts are technically coilover, and some of the aftermarket "coilover" kits keep the springs in the factory "divorced" location. Really what you're getting from a "coilover" setup is 1) ride height adjustability at each corner, which means you can also corner-weight the car, 2) use of common-size springs (e.g. 2.25" or 2.5" ID), so you can easily change rates with commonly available "race" springs (Hyperco, Eibach, Swift, etc.), and 3) depending on the level/$$$ the strut/shock valving may be much more precise than typical "street" shocks, though at the very top level it can get so precise you need a shock technician to change the valving to suit each spring rate.

Lastly, consider getting a set of track-only brake pads, doing some mods to improve brake cooling, and flushing with a good DOT 4 or DOT 5.1 (NOT 5 - that's silicone) brake fluid. Bleed the brakes before & after each track day, and completely flush once or twice per year.
 

Mad Hatter

Gotta go Faster
3,859
2,354
Santiago, Chile
Totally agree...Just a note, have a order for some P springs for a buddies car and that has been moved back til some time in October!! Bought them in July.

Would put the camber plates on the must have list. I shredded my original Pirellis at my track school when I got my boss.
 

Norm Peterson

Corner Barstool Sitter
932
706
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Maybe take a look at Billy's post #75 here:

This ^^^

It now carries an official Steeda part number.

It's possible to come up with a combination of aftermarket components combined with a little DIY fiddling that comes close in terms of roll stiffness distribution and overall roll stiffness, but that approach probably won't work for everybody.


Norm
 

Dave_W

Cones - not just for ice cream
357
345
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
It now carries an official Steeda part number.
For the '09 car of the OP, he'd need to work with Steeda when ordering to substitute the 05-10 shocks for the 11-14 shocks in the "Billy" package. Also, reading Billy's Moto-IQ build blog, Steeda initially sent him a non-adjustable 1" GT500 rear bar instead of the 1.25" adjustable bar in the kit for better traction powering off corners, but he eventually switched to an even softer 7/8" non-adjustable rear bar. Billy added camber plates to his car, which I'd definitely do as well, but they do not appear to be in the Steeda kit. Which may not be a bad thing, as it allows you to buy them from Vorshlag instead.

Billy also added the extended front ball joints and bumpsteer kit on his car (and mentioned you really need the bumpsteer kit if using the balljoints), but they may not be absolutely necessary with only a 1" front drop from the Steeda Sport springs. If you read all the articles in Billy's blog, he did a lot more work on the suspension, and there are quite a few items not in the kit he links to that contribute to the overall handling of the car Billy ended up with.

In the web page for the Steeda package that Billy links to in his article, there's a picture of some black & red urethane bushings with bolts & spacers, but no mention of them in the description - I'm thinking they may be rear LCA (obligatory BS-1 fix: "lower trailing arm") or panhard bar replacement bushings? Can't find a seperate item that looks like them on Steeda's site.
 

Norm Peterson

Corner Barstool Sitter
932
706
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
For the '09 car of the OP, he'd need to work with Steeda when ordering to substitute the 05-10 shocks for the 11-14 shocks in the "Billy" package. Also, reading Billy's Moto-IQ build blog, Steeda initially sent him a non-adjustable 1" GT500 rear bar instead of the 1.25" adjustable bar in the kit for better traction powering off corners, but he eventually switched to an even softer 7/8" non-adjustable rear bar. Billy added camber plates to his car, which I'd definitely do as well, but they do not appear to be in the Steeda kit. Which may not be a bad thing, as it allows you to buy them from Vorshlag instead.
The kit comes with the 7/8" rear bar.
Billy also added the extended front ball joints and bumpsteer kit on his car (and mentioned you really need the bumpsteer kit if using the balljoints), but they may not be absolutely necessary with only a 1" front drop from the Steeda Sport springs. If you read all the articles in Billy's blog, he did a lot more work on the suspension, and there are quite a few items not in the kit he links to that contribute to the overall handling of the car Billy ended up with.
Understood. But if you were to lower the front of your car closer to 0.5" you'd be even less likely to benefit much from extended ball joints and the attendant bumpsteer correction. BMR's 260 lb/in front springs will put you there.
In the web page for the Steeda package that Billy links to in his article, there's a picture of some black & red urethane bushings with bolts & spacers, but no mention of them in the description - I'm thinking they may be rear LCA (obligatory BS-1 fix: "lower trailing arm") or panhard bar replacement bushings? Can't find a seperate item that looks like them on Steeda's site.
All I'm seeing today is the red urethane bushings installed in the clamps for the ends of the rear sta-bar, which mounts at the ends in OE fashion. And the urethane-bushed drop links. Though that makes me wonder a bit about the adjustability mentioned in the "Package Includes" section of the product description.

He's calling for the Steeda #555-4422 rear trailing arms, which I fairly strongly feel still isn't the best approach for what should be just simple links that will not develop end moments due to off-axis rotations (even small ones). That said, there are a few things you could do to them on a DIY level to minimize what most people call "bind" and which approach the benefits of poly/spherical links without the noise (rod ends).

Somewhere else (can't find it right away), Billy stands pretty firm on retaining the OE upper, and the shorter one to boot. That makes sense on both the "roll bind" and side view geometry levels - unless you're going to go all crazy with relo brackets, link inclinations, and then having to chase axle roll steer consequences that could even involve PHB height. Which I take would have been just a bit outside the scope of Billy's tuning efforts for a dual-purpose street and road course build.


Norm
 
Thanks everyone for all of your detailed responses.

I forgot to mention I did do a full suspension build on a 2011 5.0 S197 that I had a few years back. It had GC coilovers (built for my spec), Whiteline sway bars, and pretty much BMR everything else.

With this 09 I'm not looking to get into all of that. I'm cheap with this car since it's an auto and I don't feel like it's the right platform to build. I'm looking to do a few mild suspension mods, going for a fun cruiser with occasional fun on the track, until I can get my hand's on a more capable platform (say manual 10-14 5.0 S197 or S550).

So I have to work with that in mind. The steeda shocks/springs 05-10 kit does seem to have good value at around $670. I'm open to any other suggestions though.

I'm also currently running a J&M 3 piece poly UCA (which I swapped in only because the stock bushing was dead) and GT500 LCA's. I also have GT500 Front lower control arms and GT500 strut mounts on the car. Do you think it's better if I change the J&M UCA to the Roush or OEM UCA? Will it make much of a difference?
 
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15
15
Exp. Type
HPDE
Exp. Level
Under 3 Years
Fort Worth
I think the 05-09s have taller spring rates from factory and if you are running on the original shocks and antisway bars you probably want to change all of that. Going from factory defaults to high quality new parts will make a dramatic change no matter what you pick. This post is golden for comparing and picking out springs and bars:


I think the increased cost of going from orange to yellow isn't worth it. You will get better benefits spending that money elsewhere. If you are dailying it and tracking it, a set of adjustable camber / caster plates will pay for themselves pretty quickly. As far as the springs go, there's no real downside to "picking wrong" - they are generally cheap enough that if you hate the way they feel you can replace them and sell the take offs pretty easily.
 

Norm Peterson

Corner Barstool Sitter
932
706
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
I'm also currently running a J&M 3 piece poly UCA (which I swapped in only because the stock bushing was dead) and GT500 LCA's. I also have GT500 Front lower control arms and GT500 strut mounts on the car. Do you think it's better if I change the J&M UCA to the Roush or OEM UCA? Will it make much of a difference?
Assuming that the J&M bushing is holding up, I wouldn't bother at this point. But keep an eye (ear?) on it.


Norm
 

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