Follow along as LMR walks you through all the steps to complete the 1993 Cobra-style brake booster install on your 1979-1993 Fox Body Mustang!
FOLLOW: 79 93 mustang , 5.0resto , cobra , brakes
One of the oldest past times in the long history of hot rodding has been to take other components from different trim levels of vehicles and install them on a lesser-equipped vehicle for an upgrade. Well, this is true for a '93 Cobra-style brake booster. Let’s take a trip back to the 90s; Ford Racing would release one of the best brake kits that there ever was, the M-2300-K brake kit for 87 to 93 Fox Mustangs.
This kit utilized upgraded braking components from the '93 Cobra R and the 94 and 95 Cobras. Amongst those components was the ‘93 Cobra brake booster. As time passed, the M-2300-K brake kit fizzled away into the archives, which forced enthusiasts to piece together their upgraded braking components. So, for years, Fox Mustang owners that installed better braking components would opt for a '93 Cobra booster because of its larger diaphragm, which would provide better pedal assist for upgraded braking systems.
Fast forward to today, 5.0Resto is proud to offer a brand new '93 Cobra-style booster. This booster is a direct fit for '93 Cobras and an upgraded unit for 1979 to 1993 Mustangs. It features a black e-coated finish and shares similar dimensions and tolerances to a factory '93 Cobra brake booster. Unlike other offerings, this is not a remanufactured unit. This is a brand new unit with all new components and pieces throughout. All the mounting studs are 3/8-16 thread pitch, so you can reuse your factory hardware if you choose. The actuator rod has the same inner diameter as the factory unit, which allows the plastic bushing to install right into place. Then this will be positioned over the brake pedal arm inside of the car.
On the engine bay side of the brake booster will be an adjustable brake booster pushrod that utilizes an 8mm wrench on the shaft and a 7mm wrench for the jam nut. Whenever the jam nut is loose, you can easily adjust the rod by hand and then retighten the jam nut. While we're on the topic of brake booster pushrod, it is required that you appropriately adjust this before installing the booster into the car. Failure to correctly set brake booster pushrod length will result in the pushrod being too long, and the brakes will drag, or the pushrod will be too short, which results in a low pedal; both of these situations can be very dangerous.
In typical LMR fashion, we have set aside a dedicated article on brake booster pushrod adjustment, so please check that one out. 5.0Resto’s '93 Cobra-style brake booster accepts popular master cylinders, including the SVO, '93 Cobra, and 94-95 GT master cylinders. In the box will be hardware to secure the master cylinder to the brake booster and new brake light switch hardware.
As we said before, this 5.0Resto '93 Cobra-style booster is designed as a stock replacement for '93 Cobras and an upgraded unit for 79 to 93 cars with upgrading braking systems. Now, when we say upgraded braking systems, we're talking about cars that have been converted to 4-lug rear disc or SN95 style 5-lug setups.
As far as fitment notes are concerned, there are a few. Because of the overall physical size of this booster, it will help if you elongate the holes in the firewall, and for pre-1991 cars, the old M-2300-K instructions state that you may need to “relieve” the inner area of the strut tower. This 5.0Resto ‘93 Cobra-style booster is great, especially since all you have to do when you take it out of the box is adjust the brake booster pushrod and install it on your car! No prep or paint is needed, and we break down the removal and installation steps below.
Now, we'll be the first to tell you that installing a ‘93 Cobra-style booster into a Fox Mustang isn’t the most fun thing to do because of the overall physical size of the booster, but it’s one of those things… it is what it is. Also, instead of going down the rabbit hole and explaining the differences between the boosters, this article will be focused on factory booster removal and the ‘93 Cobra-style booster installation. So depending on what you’re doing with your car will dictate how the installation process goes.
You’re either going to be in the middle of upgrading the rotors and calipers, whether it be a 4-lug rear disc or to a 5-lug SN95 set up in the front and rear and installing a new master cylinder, or like us; where everything is already in place and all you’ve been waiting on is a ‘93 Cobra-style booster. Regardless of where you’re at, this article will help provide a very detailed explanation of booster removal and ‘93 Cobra-style booster installation.
For what it’s worth, we will be working with our ‘93 silver hatchback, so a few of these steps will differ depending on the year range of your Fox Mustang.
Alright, folks! You have now successfully installed a ‘93 Cobra-style booster into your Fox Mustang. If, for some reason, you may have a few questions, give us a shout. We’ll be happy to hear from you and, of course, steer you in the right direction.
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