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Rear coilover mounting

djtrixx

New Member
Hello my fellow bucketeers! Hope everyone is having a great summer....

I'm putting together the rear suspension on my '23 t, and hit a mental block. I have a pair of qa1 140# coilovers, and am mounting them now. I've read here the standard angle is 20 degrees for mounting, but is that at ride height? Or is that a free weight? Right now I have my front end on and assembled, engine and trans in (not bolted, will have to come back out), no gas tank, body, or battery in. The rear of the frame is on jack stands, where I'd like the final ride height to be. If the 20 degrees is at free height with no weight, that angle would increase considerably. Any quick help is appreciated :)

Thanks!!!!!!!!!!!!!!!!!
 
You don't have to mount them on an angle. The 180 number you refer to is the spring rate, eg: 180 lbs will compress the spring 1'', vertically.
By moving the top mount inwards you give the rear end more leverage on the spring, making it feel softer. They do look a bit nicer on an angle though. I would think 180 lb springs a bit heavy for a T Bucket. It's all a bit of a gamble as you say without having battery, fuel etc in the rear. Springs are cheap enough though and easy to swap out once the car is done if needed. Cheers.
 
You need to contact who you got the shocks from and find out what the ride height is for that part #. The ones we sell are 12.5" so you would take 2 pcs of sq tube and drill the holes 12.5" apart and use that for mock up at ride height. Then when you install the shocks and add all the weight it should be right if you got the right spring on it.
 
I think most common are either 150 or 160 lbs. if you mount at an angle that reduces the spring rate nominally. used to be a chart in the speedway catalog , spring rate loss = angle .


dave
 
With the shocks mounted at angles it also keeps the rearend even more stable taking stress off other parts.Also looks better JMO.
 
Here is a pic of straight up shocks they are the same ones just look longer straight. My kid did me a favor and in stalled them when I was at work. He is a great welder but had some rework. one looks crooked but they where straight up changed ride height alot due to angle.
tbucket003-3.jpg


After at angle.Same shocks.
Just before I sold it due to financial things you under stand being married.:spank:

tbucketsale005.jpg
 
My coil overs are mounted at 25 degrees from vertical and 12 inches center to center on the mounting bolts. They are the same units that Ron Pope from RPM sells.

IMG_2718.jpg


Jim
 
There are several factors at work here. As stated, the inclined angle from perpendicular softens the spring rate. The distance from the center line of the tire tread also reduces the spring rate. If I recall correctly this can have a very large effect on spring rates as the leverage exerted by the rear end acting as a lever with the mounting point for the shock becoming the fulcrum. For example if the distance from the center of the rear to the center of the tread were 36 inches and the mounting point for the shock was 18 inches from each end then the rate of the spring would be reduced by 50%. (18/ 36=.5) This distance also has the same effect on the ability of the shock to control wheel bounce over bumps. Ideally the lower coil over mounting point should be as close to the wheel as possible with as little angle as possible. Both the shock and spring work best when mounted vertically.

Al
 
Mine are mounted almost vertical. This was done and there was not really much room to angle them due to my tank, body, and roll pan. I have no complaints other than the spring rate I have is a tad soft. I wil' be upgrading these coilovers to some new ones with a bit more rate.
Bens27217.jpg
 

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