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Discussion Starter #1
I just finished installing the front springs on my Whippet street rod and they chatter quite loudly when the suspension goes up and down. The insulators are in place at the top of the springs. Looking at the picture attached, are they in the correct position? Also, they compress about 1 1/4 inch. Is this enough, or are these springs too stiff for my ride? I don't know what the rate is on them, nor have I weighed my car yet.
 

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Discussion Starter #2
Sorry, but I uploaded the photo twice now, but it doesn't come up in my post. What I have is the cut end at the bottom on the outside, towards the tire.
 

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Discussion Starter #3
No help! What's up?

Doesn't anybody on this site know how to install MII coil springs correctly? I would have thought someone could help!
 

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Discussion Starter #5 (Edited)
Thanks for your reply, Willys. I was hoping I would get your attention. I tried twice to upload a picture here, but for some reason, it does not show up on my post. But if you would like to check my journal, I was able to upload a picture there. I'm sorry if I sounded frustrated, but my post was moving further down the list and wasn't getting any responses. I'll see if I can figure out the photo upload problem when I get home tonight.

Update: I think I may have been able to attach the photo.
 

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I'm not an expert but...It appears the lower control arm is pretty straight which is a good sign. 'As for the spring, it looks like it is in the correct position. I'm using a stock MII and there is a small indent that the end of the coil fits in and it is toward the tire side and looks like your spring in the way it is positioned. The trouble I had was the first springs I put in had the lower arm was at a pretty good angle and I couldn't get any motion by jumping on the front end. I put in another set that was supposedly for a Mustang with a 4 cyl. engine w/o air but the spring is physically longer although compresses more. I will have to wait and see how it handles.

Barry
 

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Discussion Starter #8
Thanks guys. I'm thinking the spring rate may be too high as when I jack up the front of the car, the cut end of the spring comes up and out of place making it necessary to pry the inboard side up for it to seat properly again. Perhaps that's why it chatters; the spring come partly out of place when the car is bounced, then settles back in, making the noise. Mind you, I don't have the shock in yet, so I will try that tonight and see if it limits the travel enough to prevent the spring from going out of place.
 

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Whippetguy said:
Thanks for your reply, Willys. I was hoping I would get your attention. I tried twice to upload a picture here, but for some reason, it does not show up on my post. But if you would like to check my journal, I was able to upload a picture there. I'm sorry if I sounded frustrated, but my post was moving further down the list and wasn't getting any responses. I'll see if I can figure out the photo upload problem when I get home tonight.

Update: I think I may have been able to attach the photo.
At first glance it looks like your lower control arms are too long. Every Mustang II IFS that I've seen or installed had the springs pretty much straight up and down with the lower control arms level with the ground. At least those that had proper geometry anyway.

Here's a pic of my truck with a Heidts Mustang II unit installed (using stock upper and lower control arms). Note the angle of the springs is almost 90 degrees to the ground. They will angle just slightly when the weight of the front sheet metal is added on but almost vertical is the way they're supposed to be. Yours have quite an angle to them and that might be your problem.

 

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The angle may be the problem but if you are still in the building stages, you can't tell a thing about how the springs will be with the car finished. Even the perfect spring will be fully extended on an unfinished car. It will do funny things in that condition. I must assume you are using a commercial setup that someone has proved in test vehicles.

Once your car is done and if the front A-arms are not parallel to the ground then you should worry. If they are angled down but the springs are still bouncy, try torching off 1/2 coil at a time to bring the front down. Works great for minor adjustments. If the springs are too stiff already torching off coils will just make them stiffer and you will need new softer springs. To see what to get you need to weigh the front of your car. Here is an easy poor-boy to weigh it using a home 200# bath scale.
 

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Discussion Starter #11
Centerline, if the lower control arms were too long, my camber would be way off, which it isn't. Maybe the angle of the photo exagerates the angle of the spring. I will take a straight on shot tonight to show the angle better. All my suspension points and upper spring mount locations are to MII spec, as measured on a stock MII crossmember. The control arms I got second hand "new", but I believe they are Heidt's control arms (correct me if I'm wrong) so I can't see the lower spring mount being out of place.
Willys, the car is very nearly finished with only the fenders and hood to go on. My lower control arms sland down only slightly, but should settle down. It does seem like the lower spring seat doesn't match the spring angle, though, and I'm not sure why, or if anything needs to be done about it. I've heard of the bathroom scale trick. I'll have to try that sometime.
When I get a better picture, maybe you guys will have a better idea of what's going on.
 

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If you got the lower arms second hand "new" they could be a custom length for a custom application. Seen it before. Get the measurements from Heidts.
 

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Discussion Starter #13
I've double checked all my measurements and everything is to stock MII specs, including the angle of the springs. This was further confirmed when I bolted the shocks to the top mount and the bottom mount lined right up without having to force the bottom end of the shock over to insert the bolt. It seems like the lower seat should be tilted to match the angle of the spring, but all the lower control arms I've seen are made this way. This leads me to think that my springs are too stiff, allowing the bottom end to came off the seat when the front end rises. I believe the springs are for a V8 MII. The diameter of the wire is about .680. Does anyone know if this jives with a V8 spring?
 

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I don't see a shock inside the coil so if you are jacking the car, the weight of the wheel/spindle causes the assembly to fall away from the spring cap and the spring becomes loose. The proper shock, properly installed will hold the spring compressed slightly and the spring will remain seated where it belongs. Bouncing the car without the shock installed really is not telling you anything and I would expect some weird noises. Having said all this, have you considered installing a set of adjustable coil overs with about 350# springs?

Trees
 

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This is an image of a Mustang II IFS with the spring in the proper location.



Looking at yours it would seem that the pocket for the spring on the lower control arm is too far out and is positioning the lower end of the spring in a location that may cause problems down the road. I don't believe what you have meets Mustang II specs, at least not for the spring location.

What kit did you use? I'd call the manufacturer and ask why the springs are angled so much. One more question... Did you mix and match parts, ie.. lower control arms made by one manufacturer, cross-member and top hats made by someone else and then use the stock upper control arms? If you did that might have contributed to the problem.
 

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Discussion Starter #16 (Edited)
:confused: :confused: :confused: This is getting somewhat confusing. The upper spring hat is straight out of a stock MII cross member. It is installed in the original location. If it was any further out, the upper control arm would not clear it. The pocket in the hat where the spring seats is at the angle you see in my photos. With the lower A arm completely out of the way, the spring naturally sits at this angle, not straight up and down. Centerline, where did you get that illustration of the MII geometry? It sure doesn't jive with the original cross member I had. The attached photo shows the stock upper spring hat with the slotted area where the upper arm mounts level side to side,as it was originally. You can see that the spring pocket is angled outward. If the spring was mounted vertically, it sure wouldn't seat very well at the top end, and wouldn't come any where near the bottom seat.
I do have the shocks mounted, but there is still enough travel for the spring to come unseated at the bottom end.
If you still doubt that my springs are at the correct angle, take a look at the installation article on Heidt's web site where they installed a MII front suspension in a 66 Mustang. You can see that the spring is at an angle similar to mine. It does seem that the spring arches slightly at the bottom, though, which reinforces my thinking that I need a more compliant spring. I think I'll phone Heidt's tech line on Monday and ask them about my problem. I'll let you know what they say.
 

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I like how you boxed in the lower A-arm area, especially since you are using strut rod eliminator A-arms. That is a huge weak point in Heidt's X-member. they don't box that in and there have been several reports of fatigue cracks and the lower A-arm breaking completely loose.

I think your creaking is normal and will go away when the whole mess gets seated and broken in.
 

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I have never seen a MII spring on that much angle when the lower A arms were level.

I think that spring is on way too much angle. I see lots of room for the upper hat to move out. Not the A arm mounts, but just the coil spring hat. Also, your hats are level. If you are to run the springs on any kind of angle, the upper hat must match the angle of the top of the spring.

You said you are using a stock hat straight out of a stock crossmember.

I went and looked at the heidts install article you refer to and yes, the springs look angled. They do not look as angled as yours though. Also, the upper hats are angled to match the spring.

I thought when you buy a crossmember you get the upper mounts also.

I don't think that a smaller wire will make the spring end settle in better. If the spring rate was too stiff that car would be sitting alot higher.

Maybe you can heat the last coil in each end until it matches the seat angle. Then quench it. You will lose some ride height doing that though and if you aren't careful you will have he car sit unevenly.

Or make an angled shim to fit in the top. Bolt it down so it doesn't move around.

Later, mikey
 

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Don't quench the spring after heating it. Let it settle and cool slowly. High carbon steel must be tempered after heating and quenching, if not it will be very brittle. Heating and cooling slowly loses the springiness but since it is the last coil that is static, doesn't matter. And it does look like the geometry of the hat is off. Why didn't you use either the entire stock X-member or the entire aftermarket one?
 

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