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When it comes to unsprung weight, lighter is always better - right up to the point where it flexes or breaks! 馃槀馃槀
Is it though? I prefer the way heavier rims make a vehicle feel.

I had a set of TSW Nurburgrings on my mustang, ended up putting the 17 inch steamrollers back on because the car rides and drives so much better with them.

Personal preference.
 

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I can think of few reasons for the ST and RS having steel over aluminum, but I really have no idea why they would develop two different types.

1. The car is built to a price point. If their is a significant price difference between the two parts, and steel is usually cheaper.
2. Steel is stronger and/or resists the nvh, torque and suspension forces these cars can generate. Aluminum is strong, until it breaks. It is not as elastic or forgiving as steel when it reaches the limit.
3. The arms are shared not just by the focus, but by another sister vehicle like an Escape or Transit. So the cost of developing both types may be justified and have other applications or virtues we haven't considered?

To bad we don't have a focus engineer to ask. :(
 

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Im running the aluminum arms they are about 3 lbs lighter and sexier looking. No place to clip on the brake deflection stuff from ford racing though.
 

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Im running the aluminum arms they are about 3 lbs lighter and sexier looking. No place to clip on the brake deflection stuff from ford racing though.
Bingo!!! Thats a game changer!!! RS comes with the brake deflectors and obviously an option for the ST.. good call!!!
 

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I can think of few reasons for the ST and RS having steel over aluminum, but I really have no idea why they would develop two different types.

1. The car is built to a price point. If their is a significant price difference between the two parts, and steel is usually cheaper.
2. Steel is stronger and/or resists the nvh, torque and suspension forces these cars can generate. Aluminum is strong, until it breaks. It is not as elastic or forgiving as steel when it reaches the limit.
3. The arms are shared not just by the focus, but by another sister vehicle like an Escape or Transit. So the cost of developing both types may be justified and have other applications or virtues we haven't considered?

To bad we don't have a focus engineer to ask. :(
The electric focus was heavier, they come in at 3,640 thanks to the batteries. They might have been trying to offset some of that weight? The electric was also more expensive, so maybe thats how ford justified the more expensive arms (especially when the electric came with a tax credit to offset that price to the customer.) On a higher production run like the standard focus, that extra cost would hurt the bottom line to greater extent
 

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Rock auto sell both, stamped or forged for Focus St at the same price. There is a severe duty one also with some kind of protective paint. No idea of the weight of each one.
 

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3 lbs less, but less than what? Is that a 10% savings or a 50% savings?
 

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3 lbs less, but less than what? Is that a 10% savings or a 50% savings?
Just to ballpark it...
I dont have the parts to weight them but per the amazon listing of the Moog stamped vs forged aluminum ones, shipping weight is 12.4 pounds and 10.5lbs, respectively. So that is a 15% weight savings. If the aluminum is actually 3lbs lighter, then you are looking at 22% (just assuming 10.5lbs and 13.5lbs. Actual savings would be greater if parts are lighter than what i am quoting and the 3lbs is accurate.

I mean is this a performance gain and worth the ~$185 cost for the arms (moog prices at rockatuo and shipping/tax/discount for me,) probably not. But if you need to replace your ball joints any ways and dont want to drill out the joint and bolt in new ones, then the price difference vs the stamped arms is worth it to me.
 

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Just to ballpark it...
I dont have the parts to weight them but per the amazon listing of the Moog stamped vs forged aluminum ones, shipping weight is 12.4 pounds and 10.5lbs, respectively. So that is a 15% weight savings. If the aluminum is actually 3lbs lighter, then you are looking at 22% (just assuming 10.5lbs and 13.5lbs. Actual savings would be greater if parts are lighter than what i am quoting and the 3lbs is accurate.

I mean is this a performance gain and worth the ~$185 cost for the arms (moog prices at rockatuo and shipping/tax/discount for me,) probably not. But if you need to replace your ball joints any ways and dont want to drill out the joint and bolt in new ones, then the price difference vs the stamped arms is worth it to me.
I'm getting ready for a front suspension general refresh at 113,000 miles currently and this looks like the ticket for the last part in the chain...鈥.
 

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Just to ballpark it...
I dont have the parts to weight them but per the amazon listing of the Moog stamped vs forged aluminum ones, shipping weight is 12.4 pounds and 10.5lbs, respectively. So that is a 15% weight savings. If the aluminum is actually 3lbs lighter, then you are looking at 22% (just assuming 10.5lbs and 13.5lbs. Actual savings would be greater if parts are lighter than what i am quoting and the 3lbs is accurate.

I mean is this a performance gain and worth the ~$185 cost for the arms (moog prices at rockatuo and shipping/tax/discount for me,) probably not. But if you need to replace your ball joints any ways and dont want to drill out the joint and bolt in new ones, then the price difference vs the stamped arms is worth it to me.
It's one of the cheaper ways to save weight on the suspension. But does it really make a make a significant difference? 3lbs on the arms is nothing compared to 3lbs off the brakes or 3lbs off the wheels lost. But weight loss is weight loss, even if the gains are not as dramatic as weight lost further out from the fulcrum.

Piecing this together, you could make a pretty expensive front end upgrade here. ;-) I mean, if cost were no object... These arms, powerflex caster bushings and powerflex camber bushings, with Hardrace roll-center tie-rod end. This could be a great performance mod with adjustable camber, better caster, roll center correction, and a lighter and stronger arm... Looking at around $1k in parts now.
 

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It's one of the cheaper ways to save weight on the suspension. But does it really make a make a significant difference? 3lbs on the arms is nothing compared to 3lbs off the brakes or 3lbs off the wheels lost. But weight loss is weight loss, even if the gains are not as dramatic as weight lost further out from the fulcrum.

Piecing this together, you could make a pretty expensive front end upgrade here. ;-) I mean, if cost were no object... These arms, powerflex caster bushings and powerflex camber bushings, with Hardrace roll-center tie-rod end. This could be a great performance mod with adjustable camber, better caster, roll center correction, and a lighter and stronger arm... Looking at around $1k in parts now.
I even bought the Powerflex (non adjustable) bushings already - maybe I'll rebuild my old arms with those, if the balljoints are still good...鈥...
 

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If they only made that center cutout a little smaller or drilled 3 holes instead of the one large one for the air deflector to fit this would be a great upgrade!
 

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It's one of the cheaper ways to save weight on the suspension. But does it really make a make a significant difference? 3lbs on the arms is nothing compared to 3lbs off the brakes or 3lbs off the wheels lost. But weight loss is weight loss, even if the gains are not as dramatic as weight lost further out from the fulcrum.

Piecing this together, you could make a pretty expensive front end upgrade here. ;-) I mean, if cost were no object... These arms, powerflex caster bushings and powerflex camber bushings, with Hardrace roll-center tie-rod end. This could be a great performance mod with adjustable camber, better caster, roll center correction, and a lighter and stronger arm... Looking at around $1k in parts now.
looking at hardrace's site now (thanks) would the aluminum arms be compatible with everything? The roll center ball joints i dont think would work, the stamped part has the three rivits to drill out and the aluminum arms seem to be designed a bit differently. You have me really considering just doing the hardrace rc ball joints and tie rods (what is the price, all i see is wish list?)
 

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different topic but has anyone compared the weight of the ST front caliper vs the RS Brembos?
 

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different topic but has anyone compared the weight of the ST front caliper vs the RS Brembos?
Yes, Brembos are lighter overall but its a bit of a trade off. The loaded Brembo caliper is lighter than the cast ST bracket and caliper combo but the rotor is heavier (no escaping the weight going from a 335mm disc up to a 350mm, more so if you were like me going from the 320mm '13 rotors.) I believe its a net savings up front all said and done but not significant. If you do the rear frankenbrake at the same time, you add weight from the caliper bracket and larger rear rotors. I noted it somewhere when i did mine but no idea where i wrote it down at. Only way to really save weight on brakes while still going bigger is if you spend money on a two piece rotor or go bonkers with carbon/ceramic. :) still, i much like my brembo's good bang for the buck, especially if you need a brake job already
 
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