Coilovers are in!

[Chief Gilly]

Installed a set of coilovers this week. What a difference in ride quality. I had H&R Sport springs with Tokico struts and I thought they looked/handled well. I set the ride height about the same with the coilovers. Going over bumps is so much better now and the feel of the steering wheel is like I have more control. I should have done this a long time ago. Bang for the buck? Hell yeah!
I went with Bilstein HD struts, #250 springs and MM C/O kit with MM C/C plates.

 

[TBapp3]

So the kit is coil overs front and rear?

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[SaratogaSaleen]

Glad you're happy with the coil over modification ... What spring length did you choose and how did you decide on that length?

I'm looking to do the same thing ... Figured out what tension I should select but not sure on the length.

 

[Chief Gilly]

So the kit is coil overs front and rear?

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In my research I found the rear is best with a watts link or panhard/torque arm setup and regular coil springs. So I have Bilstein shocks with MM torque arm springs, FRPP upper control arms with MM replacement bushing and MM adjustable HD lower control arms. I have yet to install the panhard bar yet.

 

[Chief Gilly]

Glad you're happy with the coil over modification ... What spring length did you choose and how did you decide on that length?

I'm looking to do the same thing ... Figured out what tension I should select but not sure on the length.

I went with the 12" spring. It would take it from at least stock ride height down to slammed. Plenty of travel to cushion potholes and crap. My research found 12" was the way to go and I think that is correct.

 

[TBapp3]

Keep sharing the info guys this is something iv been thinking about as well!!

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[Chief Gilly]

Keep sharing the info guys this is something iv been thinking about as well!!

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The mustang is for the most part 50-50 weight front to rear, +/- a few pounds.
So the spring rates should be approx. 50-50 front to rear. The wheel rate is the spring rate measured at the wheel. The front coil wheel rate is 25% of the spring rating. So a #600 coil spring has #150 wheel rate. A Front coilover wheel rate is 90% of the spring rate because of the changed position. So a front coilover spring rated at #600 would be #540 wheel rate. This why I believe potholes and such are not as bad because a lower spring rate can be used to achieve the same wheel rate.
The rear coil spring wheel rate is 50% of the springs rate. So a #250 rear coil spring has a #125 wheel rate. A rear coilover spring is 110% of the springs rate. So #250 coilover spring has #275 wheel rate.
Ideally, like I said, you want 50% up front 50% at the rear. This would make the car neutral. If you watch Nascar you know what I mean, otherwise it means the car does not oversteer or understeer. Panhard bars, anti-swaybars, rake of car, caster/ camber all have an effect but then it gets complicated.
So because I have #250 coilover up front I have #225 wheel rate. I have #375-440 coil spring in back, take the average= #407. 50 %= #203. So to sum up I have #225 coilover wheel rate in front #203 coil wheel rate in the rear. This setup makes my Mustang a little loose...loose is fast
Adding a bigger front sway would cause the front to tighten (or rear to loosen). A larger rear sway would make the rear tighter (front looser). So a sway bar should be the last thing to buy when doing suspension or once you are satisfied with the spring setup you have. They make adjustable sway bars for this very reason. You could adjust the balance without having to change springs.

Hope this is info you were looking for.

 

[BAzombie]

Wow Chief, that made my brain hurt.


When I was looking into spring rates for my UPR coilovers I come across articles about knowing the weight at each corner of the car. Then matching front rates with rear rates in relation to corner weights, ect. Along with stuff like you're talking about. It was all very confusing.

With all the planning I was doing with my shortblock and turbo kit I didn't want to dig that deep into the suspension info. I was recommended a 12"/200lb spring from LateModelRestoration.com and went with that. The coilovers were more a necessity for the turbo kit then for suspension mods. I figured when I get to suspension I can always buy a different spring if needed.

 

[Noterminator]

Keep sharing the info guys this is something iv been thinking about as well!!

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Do it. You've got plenty of people who will help. Suspension mods are fairly easy. The hardest part is accepting the prices lol.

 

[Chief Gilly]

Wow Chief, that made my brain hurt.


When I was looking into spring rates for my UPR coilovers I come across articles about knowing the weight at each corner of the car. Then matching front rates with rear rates in relation to corner weights, ect. Along with stuff like you're talking about. It was all very confusing.

With all the planning I was doing with my shortblock and turbo kit I didn't want to dig that deep into the suspension info. I was recommended a 12"/200lb spring from LateModelRestoration.com and went with that. The coilovers were more a necessity for the turbo kit then for suspension mods. I figured when I get to suspension I can always buy a different spring if needed.

200lb is fine, I wanted a little more rigidity. MM suggested , with the 375-440lb rear progressive, to go 350lb up front. When I run the numbers I came up with 250lb for balance purposes. Right now I still have H&R sport coils in the rear (@ 270lb) and my mustang handles great. I think once I put the 375-440lb springs in the back it may make the back too stiff wanting to come around if I get on it too much coming out of a corner. I like experimenting so I can update once I put the stiffer rear springs in. I do have the Steeda front swaybar in so thats adding to the front stiffness.
What springs are you running in the rear with the 200lb up front?

 

[TBapp3]

Lots of great info, I don't know who has the powers but this thread should become a sticky!

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[BAzombie]

200lb is fine, I wanted a little more rigidity. MM suggested , with the 375-440lb rear progressive, to go 350lb up front. When I run the numbers I came up with 250lb for balance purposes. Right now I still have H&R sport coils in the rear (@ 270lb) and my mustang handles great. I think once I put the 375-440lb springs in the back it may make the back too stiff wanting to come around if I get on it too much coming out of a corner. I like experimenting so I can update once I put the stiffer rear springs in. I do have the Steeda front swaybar in so thats adding to the front stiffness.
What springs are you running in the rear with the 200lb up front?

For the time being I'm still running stock rear springs. I'll be cutting them enough to drop about 1.5" in height.

Once I'm done getting everything buttoned up and running I'll start looking for rear springs. Still to much left to buy now. Plus I'll be hampered with the fact that I'll only need 2 rear springs and not a full set of 4.

 

[Chief Gilly]

For the time being I'm still running stock rear springs. I'll be cutting them enough to drop about 1.5" in height.

Once I'm done getting everything buttoned up and running I'll start looking for rear springs. Still to much left to buy now. Plus I'll be hampered with the fact that I'll only need 2 rear springs and not a full set of 4.

I think with having 200lb coilovers up front the H&R super sports would work best. Maximum Motorsports, I'm 99% sure, will sell the rear and front spring sets separately. So you can buy just the rear springs from them. Too bad you are upstate as i could sell you my used ones cheap. I would highly recommend their LCA w/adjustable perch. They really help out the rear, plus then you can adjust the ride height all the way around.

P.S. I buy my coilover springs from Summit, same spring $10 less. Their Summit brand is made by Hypercoil also.

 

[Finallyverted]

I second bapps idea sticky.

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[Chief Gilly]

An update on suspension upgrades for anyone interested;

I installed MM Torque Arm Coil Springs in the rear.(removed H&R Sport Springs) The Spring rate for the MM torque arm I installed is 375-440 lb/in. (H&R coils were 250-285 lb/in.) The first few hundred miles or so the ride was pretty harsh. So I got back underneath and re tightened every bolt I touched on the install and found the upper control are attachment to the axle was loose. So I tightened everything up (it actually said to re-tighten after a few hundred miles in the instructions...duh). And this mustang is now on rails! Bumps with the higher spring rate are a little more noticeable but well worth the trade off. One thing I noticed was on the upper control arm attachment to the axle there are teeth on the bushing to bite into the control arm. So if you torque the snot out of those bolts with the axle hanging, not at ride height, you would be binding up the bushing once it was at ride height. Every time you raise up the body and let the axle hang you are twisting those bushings.
At 95,000 miles my rubber bushings were dry rotted. When I purchased the new FFRP upper control arms from MM it came with new Rubber bushings at the body attachment. I bought the replacement rubber axle bushings that MM sells, as they recommend staying with rubber on the Upper Control Arms. (I went with the 3 piece Urethane bushings on the LCA body torque arm attachment and the Teflon-lined spherical bearing at the axle attachment).
My Mustang is awesome to drive now, much much better than stock, absolutely no wheel hop now. If you guys think installing new coil springs like H&R or Eibachs on all 4 corners gives you a better handling ride installing the Coil-overs up front and these torque arm coils out back is like night and day in comparison. I had H&R Sort Springs up front, don't get me wrong it was better, but like I said the Coil-overs are a different realm of control.

P.S. I have the bushing removal/install tool if anyone on Long Island needs to borrow it if installing new bushings.

Next Up I would like to see how 350 lb/in coil-overs work up front as that is what MM suggested to begin with. I have 200 lbs/in now.