[deaks]

My car came with QA1 single adjustable coilover front shocks but the front end seemed high, they banged a lot on bumpy roads and I could hardly push the front down at all, even with the damping on full soft. Anyway I adjusted the ride height to the bottom setting but it's even worse now. Measurement is 26" from floor to wheel arch. I'm thinking that maybe the springs are wrong, or possibly shocks are too short but I haven't dropped one off yet.
Mick

 

[MSMach1]

Are you running a stock style Mustang front end?
I am trying to figure why you would have additional springs/coil over setup on that type of front end?
A picture would help out here.
In general, the spring is designed to support the car load and the shock controls the spring oscillation rate.

 

[Huskinhano]

Coil over has become such a buzz word. Look at a proper coil over system like the Street or Track. The spring and shock mounting point is moved to the lower arm and close to the ball joint. This does two important things. You get a longer shock that carries more fluid, runs cooler and has more finite travel. Same for the spring. The other is moving everything closer to the ball joint allows better motion ratio which is just saying they work more efficiently.

If it were me, the first thing I would be doing is removing it and installing a roller bearing spring perch, GT spec coils and a set of either Koni or Bilstein shocks. The Bilsteins sold through Street or Track are basically custom calibrated for our Mustangs. I have the Bilsteins and they are absolutely wonderful. I don’t have too much experience with Koni but I’m absolutely confident they’ll work equally well. Not going wrong with either.

 

[DonP]

Some pics might help. But I’d take measurements at the shock and compare it to QA1 specs. I believe the shocks should be about 2/3 compressed at static ride height. [Edit: QA1 site says 25-30%]
Looking at QA1 ads, it looks like the spring rate is printed on the springs.

 

[Tom1500]

The spring rate and spring length is most likely incorrect, leading to the suspension being near too or completely bottomed out, or the spring at coil bind. The compression damping is also very high on these shocks. Common issues with these QA1 coilover kits.

Do you have your current spring part number? Suggest someone here with a similar coil over kit will be able to recommend a suitable spring to fix your issue.

 

[deaks]

The spring rate and spring length is most likely incorrect, leading to the suspension being near too or completely bottomed out, or the spring at coil bind. The compression damping is also very high on these shocks. Common issues with these QA1 coilover kits.

Do you have your current spring part number? Suggest someone here with a similar coil over kit will be able to recommend a suitable spring to fix your issue.

Thank you, very useful advice. The spring doesn't look coil bind, i'm leaning towards maybe, shock length being wrong. I'm going to take one off and see what numbers and measurements I can get.

 

[Tom1500]

Thank you, very useful advice. The spring doesn't look coil bind, i'm leaning towards maybe, shock length being wrong. I'm going to take one off and see what numbers and measurements I can get.

Removing the spring and sway bar, but reinstalling the shock, you should be able to cycle the suspension by hand and see where you are at/ check for obvious issues. Depending on your LCA bush it may still take a fair bit of force to do this though.

Measure your ride height from the wheel centre to the guard lip so you have a reference off the ground.

 

[DonP]

View attachment 886516

In that picture the spring doesn’t look like what I see online for their kits.
The spring coils are smaller in diameter at the bottom where it sits on the ring.

 

[DonP]

A coil spring is just a wound up torsion bar. A smaller diameter equates to a shorter bar. Shorter is stiffer.

 

[GT289]

My car came with QA1 single adjustable coilover front shocks but the front end seemed high, they banged a lot on bumpy roads and I could hardly push the front down at all, even with the damping on full soft. Anyway I adjusted the ride height to the bottom setting but it's even worse now. Measurement is 26" from floor to wheel arch. I'm thinking that maybe the springs are wrong, or possibly shocks are too short but I haven't dropped one off yet.
Mick View attachment 886516

Gee. I'll play. (nice control arms ya got there)
What's the wire diameter on the spring/do you know the rate?
Usually single adjustable shocks only vary the rebound via the adjustment. And if the single knob does
vary both bump and rebound, it's almost guaranteed to not be the correct ratio. Roughness in bump on the front
end is softened through spring rate and the ability to correctly adjust bump & rebound in the shock.
Just a few things that come to mind.

ex-Global West GM
1991-1995

 

[deaks]

 

[deaks]

Hope this helps, coil thickness is 13.5mm. Note the top is not raised like a conventional shock but I believe the bottom position is different as well, due to the aftermarket arms.

 

[deaks]

 

[deaks]

Note the upper mount is flat, not raised.

 

[rpm]

500 lb is way too much spring. The Windsors usually take a 300 to 350 rate spring.

 

[GT289]

He’s right. Specs out at 500/in. I was thinking something at least 430-ish. And a double adjustable shock….

ex-Global West GM
1991-1995

 

[DonP]

Note the upper mount is flat, not raised.

That shock is either close to bottomed out or it is shorter that their current kits. I'd toss that old QA1 kit as a whole.
And I'd probably try it without a sway bar just to see how that works out while I waited on the new parts.

 

[deaks]

I'm not racing the car, just want a nice smooth ride over the bumps, as the roads are very poor round here. I don't know what should be on it because it was all fitted when I bought the car, just trying to make it work and that doesn't involve replacing it all.
Thanks for your replies. I might have to speak to QA1.

 

[rpm]

500 lb is way too much spring. The Windsors usually take a 300 to 350 rate spring.

Eh...nevermind. I was thinking of the springs where the shock mounts to the lower control arm.

 

[rpm]

Just checked with a buddy who has the Viking front coil overs, and he uses the 350 spring. His 65 has the best ride and handling feel of any Mustang I've been in.