Installation Instructions For Cornerkiller Front Steer Suspension Kits
This set of instructions have been put together so the average guy should be able to put an updated suspension kit on their hot rod or street rod project. You do not need to understand, or have a degree in front end geometry to be able to successfully install the hub to hub Cornerkiller Custom Suspension Kit. Updating your project to 11″ cross drilled and slotted disc brake rotors, coil over type suspension, and rack and pinion steering for improved handling and performance can be accomplished if you have basic welding skills, can read a tape measure, and use a level.
Here is a list of the things you will need for a successful installation of your Cornerkiller Suspension Kit
Working off of a level surface is a must with these instructions. The floor must be level from side to side, a level surface from front to back is best but not required.
- A Tape Measure a 20′ tape that measures to a 1/16″ is ideal.
- Levels a 4′ level and a 6″ magnetic level work best.
- A Welder. I use a MIG (wire feed) to tack everything in place, but a TIG or a stick welder will also work.
- A Square a quick square works well but a carpenters square is sufficient if that’s all you have.
- A Scribe and a Permanent Marker or Soap Stone
- A Hand Held 90 degree Grinder and a Cut off wheel
- A 5/8″ x 18 TPI Tap to clean the threaded bore in the upper control arms
- Jig Sticks – 2 flat bars 1″ wide 1/8″ thick 13 1/4″ long with two 1/2″ holes 12 1/2″ center to center
- A set up Wheel and Tire. This needs to be one that you will be using on the finished project and will need to be inflated to the pressure that it will be run at on the vehicle.
In most cases the best place to start is the beginning. Using these instructions you will be starting from the end.
Let’s get started.
Positioning Your Project
The first thing you will need to do is place the Vehicle into a level side to side work area. If working off a concrete slab, place a 4′ level on the floor at the vertical spindle center and make sure the floor is level from side to side. If it’s not, use a piece of sheet steel or 1/2″ plywood to level the floor. Once the floor is level position the project at the exact ride height and posture or rake that you want the finished project to be. You will be installing all components in a loaded state so there is no need to compensate for engine weight ect. This is the desired ride height and posture that you want the finished project to be when it’s all put together and driving down the road.
Establishing The Vertical Spindle Center Line
The factory vertical spindle line should be scored on the frame rail BEFORE the original suspension is removed. In some applications, like a ’53 to ’56 Ford F 100, it is desirable to move the vertical spindle center point forward 3/4 of an inch or so to better center the wheel and tire in the wheel well.
If the factory suspension has been removed prior to set up, you can simply use the set up wheel and tire to find where it is best centered in the wheel well opening and then mark the center of the wheel and tire on the frame rail.
It is imperative that the vertical spindle center line be located in the same place on both sides of the vehicle so a reference point on the frame rail that is consistent on both sides should be used to measure and make sure that both sides are in exactly the same place.
The Cross Member and Upper Brackets in this Kit are NOT Centered on the Vertical Spindle Center-line.
Once the vehicle is loaded into the work area, and the vertical spindle center line is established on both frame rails, you’ll need to put a level across the frame rails at the spindle center line to verify that the frame rails are level.
The first component of the kit to be installed is the center section of the cross member. If your vehicles frame is an open C channel, the frame rails will need to be boxed off before the cross member can be installed.
Boxing plates for specific applications such as 1964 to 1970 Mustang and 1948 to 1956 Ford trucks are available. If the frame rail is at a constant height, then flat plate steel of the same gauge as the frame rail may be used . The frame will need to be boxed for a minimum distance of 18″ centered on the vertical spindle center line to install the cross member.
Some people like to box the frame from the firewall to the front of the frame, I personally like to box the frame from front to back .
The cross member in this kit will need to be notched to establish both desired ride height and to fit between the inside of the boxed off frame rails. Before we discuss how to determine where the notches in the cross member will be located, we need to discuss the spindles.
You are setting the vehicle up at your desired ride height. Use of a 2″ drop spindle or a stock ride height spindle do not affect ride height, but rather how deep onto the frame rails the cross member is placed.
Your horizontal spindle center point will be in the same place with either spindle. 2″ drop spindles allow you to install the cross member 2″ lower in the frame rails to provide better oil pan to rack clearance. This is highly recommended on some applications like the 1964 -1970 Ford Mustangs.
Previously we established the vertical spindle center point and scored it’s location on the frame rail. Now we need to establish the horizontal spindle center point. To do this the following formula works well.
All Measurements in these instructions are examples to show how the formulas work!
Please use the measurements from your project!
Stand the set up wheel and tire on it’s tread surface as if it were on the vehicle. Measure from the ground up to the highest point of the tread surface. This is the inflated tire diameter. I will use 28″ as an example, but you will need to use your inflated tire diameter in the formula to develop your horizontal spindle center.
We need to divide the inflated tire diameter by 2 and subtract 1/4″ for the flattening of the tire under the weight of the vehicle. So 28″ divided by 2 = 14″ – 1/4″ = 13 3/4″ By the example 13 3/4″ is the horizontal spindle center point. This is where the horizontal center of the spindle will be located with a 28″ tire no matter what your ride height is set at.
2″ Drop Spindle Vs. Stock Ride Height
On the initial installation a 2″ drop spindle does not change the ride height. You are choosing your ride height on the initial set up of the vehicle. 2″ drop spindles allow you to mount the cross member 2″ lower in the frame rails and allows more clearance between the oil pan and the rack and pinion. The Cornerkiller Custom Suspension kit is designed to lower the vehicle at least 2″ and can lower the vehicle up to 6″ with a stock ride height or a 2″ drop spindle. Since the vehicle is set up at your desired ride height, you can determine whether you need a stock ride height or an optional 2″ drop spindle like this :
Measure from the ground up to the side of the frame rail @ the vertical spindle center point 13 3/4″ (By our example) and place a mark on the frame. If this mark comes out below the frame rail it’s ok, this is a common occurrence and will depend on where your ride height is set at.
If it comes out more than 2″ below the frame rail, you should rethink your ride height. If the horizontal spindle center point comes out in the lower 50% of the frame or below, a stock ride height spindle will be best for your project unless your project requires a 2″ drop spindle for oil pan to rack clearance. If it falls in the top 50% or above the frame rail, you will be better off with a 2″ drop spindle for your project. Some applications like a 1964 to 1970 Mustang require a drop spindle for added Engine clearance.
Using a stock ride height spindle, the lower control arm mounting hole will be located 3 1/2″ below the horizontal spindle center when the cross member is installed and tacked into place.
With a 2″ drop spindle the center of the lower control arm mounting hole is 5 1/2″ below the horizontal spindle center point.
Our example uses a 28″ tall tire so our horizontal spindle center is @ 13 3/4″. For our example we’ll say that 13 3/4″ measured from the floor comes to 1″ above the bottom of the frame so we will use a stock ride height spindle.
If we subtract 3 1/2″ from 13 3/4″ that would place the center of the lower control arm mounting hole @ 10 1/4″ off of the ground when the cross member is installed.
The cross member needs to be located so that it is level front to back as well as side to side , so the lower control arm mounting holes will be 10 1/4″ from the ground at all four points when the cross member is tacked into place.
Marking the Reference Points
This is a good time to mark the 4 reference points on the frame rails where the front and back walls of the cross member will be located. The cross member with this kit is 3 1/8″ wide from outside to outside of the front and back walls. It is off set not centered on the vertical spindle center when correctly placed. You will need to measure (1″) forward (towards the radiator) and (2 1/8″) behind (towards the firewall) of the vertical spindle center point to correctly locate the cross member. Mark the 4 reference points all the way around the boxed off frame rail. These are the points where the front and back walls of the cross member will be located.
When figuring where the notches will be placed in the cross member, you should keep in mind that the notches in the front side of the cross member and the notches in the back side will almost always be different. You need to do the math at all four points.
We know that the center of the lower control arm mounting holes will be 10 1/4″ (by our example) from the ground (at all 4 points) when the cross member is in place, so we need to measure the distance from the bottom of the frame to the ground at all 4 of the reference points one at a time. It’s important to do the math at all four points to compensate for any inconsistencies in the frame rail and to avoid the possibility of welding a gap. You want a good tight fit with the cross member and it must be level front to back and side to side.
I’ll start with the driver’s side reference point that is 1″ forward (towards the radiator) of the vertical spindle center point. For our example lets say that from the bottom of the frame rail to the ground is 13 1/4″ .
If we subtract the distance of the lower control arm mounting hole to the ground 10 1/4″ from the distance of the bottom of the frame to the ground 13 1/4″ that gives us a difference of 3″.
We would then measure on the left front corner of the cross member from the center of the lower control arm mounting hole up the side wall 3″ and place a mark. This is the location of the horizontal notch in the cross member.
Next we’ll measure for the drivers side rear. I like an inch or two of rake on my projects so the drivers side reference point behind the vertical spindle center from the bottom of the frame to the ground we will say is 13 1/2″.
If we subtract 10 1/4″ from 13 1/2″ we have a difference of 3 1/4″.
Measure from the center of the lower control arm mounting hole on the back side of the cross member up the side wall 3 1/4″ and place the mark. this needs to be done at all four points for the cross member to fit tight and come out level.
We now have a horizontal notch marked on all four corners of the cross member so we need to figure out where the vertical cuts will be. It is important that the Cross member is centered between the frame rails. Frame rails almost never run parallel so once again the front and back vertical cuts will almost always be different.
Measure the over all width of your cross member. The one for our example is 31 1/4″
Measure the inside to inside of the frame rails at the reference points forward of the vertical spindle point. For our example we have a measurement of 25 3/4″.
This is an Example Please use your measurements in the formula!
Here’s the formula : 31 1/4″ – 25 3/4″ = 5 1/2″ now divide 5 1/2″ by 2 = 2 3/4″
Measure from the outside edges of the cross member in toward the center 2 3/4″ on both sides of the front of the cross member and place marks. These are the locations of the vertical notches on the front side of the cross member.
Repeat this procedure using the reference points for the back side vertical cuts.
Now you should have a vertical and horizontal cut marked on all four corners of the cross member. Simply lay your square on these marks and draw a line around it. This marks the notch that will be cut out. Once the notches are cut out test fit the cross member into the frame rails. Tack it into position when you have verified that you have a tight fit and a measurement of 10 1/4″ from the center of the lower control arm mounting holes to the ground at all four points. You can massage the notches with the grinder if necessary to achieve perfect placement of the cross member.
Placement of the Upper Control Arm / Shock Mount Brackets.
These brackets are referred to as Top Hats
With the cross member notched and tack welded into it’s proper location it’s time to set the Top Hats. We will need to prepare to do a mock-up of the suspension. Use the 5/8″ x 18 tap to clean out the bore in the upper control arms. Lube the bore in the upper control arms with the lubricant of your choice, I recommend Dry graphite but anti-seize works too.
Locate the 4 bushing adjusters for the upper control arms and screw the jam nuts all the way up to the bushing end. Install the adjusters into the upper control arms all the way until the jam nut comes into contact with the control arm. Screw them back out so you have a distance of 1/2″ between the control arm and the jam nut. This places the adjusters in the middle of the adjustable area for caster and camber settings.
Install the upper control arms on to the Top Hats with the 11″ long 5/8″ bolts that were provided with the kit. Be sure to install the Belleville washers on the inside of the bushings at all 4 locations. The cupped shape faces the bushing. There is a left and a right Top Hat. Install the upper control arms so the ball joint is pointing down with the shock mount facing out. The upper control arm mount is higher toward the front of the vehicle. This is a built in 3 degrees of positive caster or an anti – dive angle. Set the assembled Top Hat / upper control arms to the side.
Install the Lower control arms onto the cross member. The front side of the lower control arm runs almost parallel with the cross member while the back side of the control arm angles toward the rear of the vehicle. Install the 4 remaining Belleville washers at the inside of the control arm bushings (cup shape facing the bushing). Block the control arms up so that they are straight out level with the ground. Install the spindle on the lower control arm. There are 2 spacers provided on each Ball joint. The flat washer style spacer goes on top of the ball joint boot, then the spindle goes on, next the 3/8″ thick spacer, and last the slotted nut. All four ball joints are assembled in this order or you will not be able to properly seat the ball joint taper into the spindle.
Stand the spindle up so it points straight out sideways at zero camber. Zero camber can be determined by placing a 6″ magnetic level vertically on the caliper bracket bolt holes on the back side of the spindle. Install the upper control arm / bracket assemblies making sure that the Upper control arm mount is higher in the front than in the back and the shock mount pointing out. Set the bracket down on top of the frame rail. Line up the brackets on the reference point marks.
The Tophats need to be set using three critical measurements.
You need 12 1/2 ” between the upper shock mount and the lower shock mount in a loaded state. Install the Jig sticks to hold the brackets at this measurement.
- You need 9 1/4″ with a straight up vertical measurement from the center of the lower control arm mounting point to the bottom of the upper control arm mounting tube at the vertical spindle center point. This point can be established by measuring 1/4″ down from the weld on the upper control arm mounting tube on the front side of the bracket (top hat) and place a reference mark. We can add 9 1/4″ to the center of the lower control arm mounting hole to ground measurement (10 1/4″ by the example) 9 1/4″ + 10 1/4″ = 19 1/2″ (please use your measurements in this formula) this will give us the distance from the ground to the reference point on the top hat. The Top hat can be mounted as much as an inch higher than this but the 9 1/4″ measurement is optimal. The top hat can be trimmed at an angle to achieve the first two critical measurements. Sometimes with extremely low ride heights it is necessary to build a platform on the frame to set the top hats. The goal is to achieve these first two critical measurements.
- You need the front of the upper control arm mounting tube to be 3/8″ higher than the back side of the tube from a true horizontal plane. I accomplish this by setting the 6″ magnetic level on the outside of the frame rail and measure to it with it level.
- Once these 3 critical measurements are set, adjust the top hat in or out to achieve zero camber then tack weld into place.
Remember that these measurements are for a 28″ tall tire and a stock ride height spindle.
If you’re using a different size tire or a 2″ drop spindle your measurements will be different.
Please use these as an example and do the calculations with your measurements.
Mounting the Rack and Pinion
The proper placement of the Rack and Pinion brackets on the cross member is important to avoid the possibility of Bump Steer. The steering arms on the rack need to run parallel to the lower control arm when it is installed and parallel to the ground.
To do this bolt the rack brackets onto the rack and pinion with the spacers in between the two. The spacer is there to provide clearance between the tie rod end and the lower control arm. Install the tie rod ends onto the steering arms on the rack. Install the tie rod ends up through the steering arms on the spindles.
On the front side of the cross member you will find reference lines scored into place to center the rack from side to side. Line the rack brackets up with these lines and place the rack up against the front of the cross member. Raise or lower it until it is a at point where the steering arms on the rack are parallel with the lower control arms and the ground.
In cases where you have chosen an extremely low ride height, it may to be necessary to C – notch the bottom of the frame rail for additional steering arm clearance.
It is important that the rack and pinion steering arms do not run down hill or up hill to the spindle. Once the proper location is found, either mark the position of the rack brackets or tack them into place. You can now remove them from the rack assembly and weld them down to the cross member without the risk of damaging the bushings.
Set your initial alignment specifications and confirm your final geometry. If everything is good to go you can weld it all down solid and do a final assembly.
Please read these instructions from beginning to end at least twice!
If you have any questions you can shoot me an email to
or give me a call @ 503-268-7453