You don't have to but I would get them in the near future. you'll know if you caster camber is off by looking at your tire wear. i would also get, later, offrack steering bushings, steeda balljoints and bumpsteer kit. better struts.

 

All of that stuff isnt necessary. Eventually your shocks/ struts may blow. If you do get c/c plates then get 4 bolt, not 3. The only other thing you might want to get is the bumpsteer kit.

 

Not to necessary, once you lower it, the suspension geometry is off, CC plates will help, maybe not to noticeable, but little things help it get to the correct specs once it's lowered.When a Mustang is lowered, the front roll center changes due to the new
position of the suspension pivot points. Lower the car too much and the
front roll center drops to well below ground level, and worse than that,
the roll center moves side to side as the body rolls, resulting in lost grip
and erratic handling. The lower roll center causes the body to roll more
easily. Countering this tendency usually requires a significant increase in
front spring rate to simply control the added roll due to the lowered the roll
center. This higher spring rate not only hurts ride quality, but it also
reduces grip on rough surfaces, as the stiffer springs cause the tire to skip
over bumps instead of following the contours of the road but i would get the offset steering rack bushings, the bumpsteer will be good also. The other stuff will just compliment your suspension more.

 

For a DD car that isnt seeing any autocrossing or a good amount of drag racing, its not necessary. But you are correct.

 

Offset steering rack bushings are what Saleen was alluding to. They're quite useful in some cases at restoring jacked up steering geometry.

If you don't get the CC plates I'll bet you 10 bucks you have substantially increased tire wear. It's just really hard to get a good alignment if you can't adjust the camber back to something approaching normal. You don't need lots of camber on a DD, so you're shooting for probably -.5 - -.8. The bumpsteer kit will help but it has to be set correctly or it can make things worse. You'll need to have your bumpsteer measured after you have the springs installed and they settle for a week or so.

Steeda ball joints will help with handling as well but aren't toally necessary. They're nice to have though. Shocks and struts will really help reign in the ride and you'll need them eventually anyway since stiffer springs wear the stockers out after a variable while.

As far as plates go, maximum motorsports or don't even bother. Ask anyone for 2 names of plates they'd buy and MM will be one of them, for a good reason.

 

Yep, MM 4 bolt here.

 

with a bumpsteer guage from Maximum motorsports. The camber spec i gave you has seemed to be the best comprimise between handling and tire wear. Stock is basically straight up which blows. You'll want to max out the caster and set just a pinch of toe in. Those specs always seem to be really well received by the tires. Stock never seems to work well.

For struts and shocks, I like Bilstein but they're rightly pricey. Tokico Blue's are fine and quite appropriate, Illuminas if you want adjustability. Koni also make nice units. The ball joints will repair handling issues and your stockers will probably never wear out. So if you're goiing to replace them it's for the handling correction more than durability. In such case, steeda X2 is my choice (and I hate steeda so that's saying a lot). CC Plates are cake...shouldn't take an hour.

FWIW, you've started down a road that has no end and no map. When you tinker with suspension and braking and power like stang drivers like to do, you have to abandon much of the specs for stock and change them correctly for modified use. Alignment settings are but 1 of those zillion changes. From here on it gets to be more trial and error than known values. Have fun.