1979-2023 Mustang K-Member Buyers Guide

When looking into replacing your Mustangs k-member with a lightweight version, there can be many options that you will sort through to find out what is the best choice for your project. Choosing the correct tubular K-member will come down to what you want to achieve on your project. Selecting the correct K-member comes down to two essential steps:

• Step 1: What engine will you be running?
  • Push rod, Coyote Swap, Modular, Godzilla, or LSX Swap
• Step 2: What suspension and a-arms will you be running?
  • Factory A-arm with coil spring or coil overs
  • Tubular A-arms with coil spring or coil overs

What are the benefits of running a tubular or aftermarket k-member on your Mustang?

The most common reasons people install a k-member on their Mustang include weight reduction over factory k-members, extra clearance for headers, oil pans, and turbo piping. Even though the k-members may weigh less than your factory k-member, that doesn’t mean they are weaker. Many manufacturers, such as UPR, will use chrome moly tubing to ensure that the k-member is safe and reduces flex under even the hardest launches or corning at the track.

Step 1: What engine will you be running?

The engine you will run in your Ford Mustang will be vital in selecting the correct aftermarket tubular k-member. If you want to keep the factory-installed engine or swap a different engine into your Mustang, you will need to ask yourself this main question - What engine are you going to run in your Mustang? Some of the most popular options include:

• 302/351 Windsor-based engine
• 4.6L/5.4L Modular engine
• 5.0L Coyote Engines
• 7.3L Godzilla engine
• LSX

Shop our complete line of Mustang K-members below. NOTE: Pay attention to fitment and product notes to ensure the engine you plan to run in your Mustang matches the k-member fitment.

Step 2: What Suspension Are You Planning On Using?

Once you have chosen what engine you will be using in your Mustang, the next step you will need to decide is what type of suspension you are planning on using on your Mustang. This will come down to two choices:

• Will you want to retain factory coil springs or switch to coilover suspension?
• Do you want to retrain factory a-arms and run aftermarket tubular a-arms?

Factory Spring Setup v. Coil-Over Suspension

Factory Coil Springs:

Your choice will be limited if you want to retain the factory front springs and a-arm setup. We highly suggest you look at fitment notes and ensure the k-member you selected supports factory coil springs. This is a popular option for many Mustang enthusiasts as it allows you to keep the factory coil springs and strut assembly. This combination is tried and true on the race tracks and tends to have less NVH than coilovers. Here is a common option a lot of Fox Body Mustang customers go with that want to retain factory front suspension, run tubular front control arms, and a 5.0L pushrod engine:

1979-1993 - Windsor Base 302/351 Only

• BMR Premium Spring Perch K-Member Kit - Standard Ball Joint - Black Hammertone

Coil-Over Setups:

To save additional weight and convert to a coil-over setup, you must decide how your Mustang will be used/driven. The spring rates on coil-overs will help you dial in your Mustang, allowing the best performance on the track.

Use the below information to help you choose which coil-over spring rate will best suit your Mustang driving style, or refer to the Mustang Coilover Conversion Guide for additional information.

Please Note: Increased noise, vibration, and harness (NVH) can be expected when converting to coil-over. You will also want to check the product notes on each coil-over for the correct strut fitment. Coil-overs will have specific fitment depending on the strut you plan on running.

Choose Your Coil-Over By Driving Style

Once you have chosen your K Member, you will want to select the coil-over best suited for the driving style of your Mustang.

• Street/Strip Driving/Drag Racing - LMR suggests a 12"-14" 150lb-200lb spring setup. These kits will give your drag Mustang a great weight transfer for the strip. These spring rates will help with overall weight transfer on the drag strip. The taller springs used on these applications will allow the vehicle's front end to raise and allow the rear end to squat more. If your Mustang is a drag strip only vehicle, then you will want to lean more towards the lighter end of the spectrum, 150lb-175lb, with a taller 14" spring. For a daily driver that you occasionally take out on the weekend, the higher 175-200lb rates and 12" springs will be better suited for you.
• Street Driving - LMR suggests a 12" 225lb-250lb spring setup. These kits will give you adjustable ride height and improved handling characteristics. Normally, these rates offer you the best overall ride quality for a daily driven street vehicle. You will purchase the K-member of choice and the following coil-over kits on step 2 for these setups.
• Performance Driving - LMR suggests a 10" 275-300lb spring setup. These kits will perform better than a normal street kit but can still be used for light track use. The 275lb or higher rates can heighten NVH and overall ride quality on the street. These applications would be recommended for occasional street use only.
• Auto X & Road Race Driving - LMR suggests a 10" 350lb-400lb spring setup. These kits will perform greatly on the track for any auto x and road racing events. Due to the high spring rates on these coil-overs, the ride quality will be sacrificed with these kits. If you are going this route, we recommend these to be for competition/off-road applications only.

Other Parts to Consider While Purchasing A K-Member

Caster Camber Plates:
All aftermarket k-members with coil-overs will require spherical bearing caster camber plates. The best rule to follow here is to make sure you match brands. For example, if you run a Maximum Motorsports K-member, ensure you run Maximum Motorsports A-arms and caster camber plates. If there isn’t a matching brand, just be sure you get good spherical bearing caster camber plates.

An example of this would if you owned a 1996 SVT Cobra and you opted for the following Team Z k member kit, you would be best to choose the following caster camber plates: Team Z Caster Camber Plates (94-04)

• Team Z Matrix Tubular K Member Kit w/ 12" 150lb Springs - Modular (94-04)

Motor Mounts

For most Mustang K-members, engine mounts are not required; however, there are a few exceptions, such as Team Z Motorsports. Be very careful and read all fitment notes on K-members, as some are incompatible with certain brands or styles. Late Model Restoration works hard to note all of this in the vehicle fitment notes on our product pages.

In closing, always double-check all fitment notes on the parts you purchase to reach out to our knowledgeable customer care team with any questions you may have before making your k-member purchase.