08-21-2009, 05:27 PM
Traction Lock
From the factory, most first generation Mustangs came with an open differential, meaning only one tire will spin once traction is broken. Many will install Traction Locks to help transfer torque more evenly between the wheels when traction is broken.
Gearing
The most common stock gearing was 3.25 in the first gen Mustangs, but many came with 2.73, 3.90, 4.11, etc gearing. Sometimes the stock gearing becomes too much for the owner, especially with the cars with 4.11s and 4.30s. In these cases, the gearing is often swapped for 3.25s or similar. Other times the 2.73s or 3.25s leave something to be desired in acceleration, and they are swapped for 3.90s, 4.11s, etc. Keep in mind when choosing a gear, that the first gen Mustangs do not have an overdrive gear from the factory, and when dealing with the steeper gears, you'll be pulling high RPMs at highway speeds.
Exhaust
The stock first gen Mustangs usually came with single exhaust, but even those with dual exhaust leave a lot to be desired, such as sound, and extra power. The stock exhaust manifolds are pretty restrictive in most cases, and often a lot of power can be found by installing a set of headers, usually from Hooker's Competition or Super Competition line of products.
Past the manifolds/headers, the stock tubing is sized on the small size and can be replaced for more power, along with new freer flowing mufflers. The most common choice for mufflers being Flowmasters.
Shifters
The stock shifters in these cars aren't known for their precise, short, or accurate shifts. If you're looking to improve on your shifting time, check out Hurst's Competition Plus shifter. Even if your particular Mustang came with the factory Hurst, it is old technology compared to the newer Hurst shifters, not to mention the fact that it is 30+ years old.
Carburetors
Many times the stock carburetors on the first gen Mustangs were much smaller than the motor would like to have. It is such an easy item to change, that its often one of the first things to be tossed in favor of, say a Holley 4150, which is the #1 choice of Mustang owners.
Springs
Most of the 30 year old Mustangs have worn out leaf springs in the rear causing them to droop. This is corrected by a new set of springs, and is often upgraded with a set of heavy duty leaf springs with a higher rate in order to make the car handle better. Rear springs are available in 4 leaf, 4 1/2 leaf, and 5 leaf versions, as well as normal, mid, and reverse eye configurations. The mid eye generally lowers the rear 1", and the reverse eye 1 1/2-2".
The rear springs can be complimented by a new set of front springs. An ever popular choice is the Grab-A-Track springs, which are available in both 620lbs and 720lbs rates. Either is much higher than the stock rates, and will lower the front 1", as well as offer less body roll and better handling.
Shocks
If you change the springs out for a stiffer aftermarket set, then you'll need a set of good shocks to compliment them. Not only will the handling be improved, but the ride will be smoothed out quite a bit by a good set of matched shocks and struts. Koni and KYB are two very popular choices for upgrading the first gen shocks.
From the factory, most first generation Mustangs came with an open differential, meaning only one tire will spin once traction is broken. Many will install Traction Locks to help transfer torque more evenly between the wheels when traction is broken.
Gearing
The most common stock gearing was 3.25 in the first gen Mustangs, but many came with 2.73, 3.90, 4.11, etc gearing. Sometimes the stock gearing becomes too much for the owner, especially with the cars with 4.11s and 4.30s. In these cases, the gearing is often swapped for 3.25s or similar. Other times the 2.73s or 3.25s leave something to be desired in acceleration, and they are swapped for 3.90s, 4.11s, etc. Keep in mind when choosing a gear, that the first gen Mustangs do not have an overdrive gear from the factory, and when dealing with the steeper gears, you'll be pulling high RPMs at highway speeds.
Exhaust
The stock first gen Mustangs usually came with single exhaust, but even those with dual exhaust leave a lot to be desired, such as sound, and extra power. The stock exhaust manifolds are pretty restrictive in most cases, and often a lot of power can be found by installing a set of headers, usually from Hooker's Competition or Super Competition line of products.
Past the manifolds/headers, the stock tubing is sized on the small size and can be replaced for more power, along with new freer flowing mufflers. The most common choice for mufflers being Flowmasters.
Shifters
The stock shifters in these cars aren't known for their precise, short, or accurate shifts. If you're looking to improve on your shifting time, check out Hurst's Competition Plus shifter. Even if your particular Mustang came with the factory Hurst, it is old technology compared to the newer Hurst shifters, not to mention the fact that it is 30+ years old.
Carburetors
Many times the stock carburetors on the first gen Mustangs were much smaller than the motor would like to have. It is such an easy item to change, that its often one of the first things to be tossed in favor of, say a Holley 4150, which is the #1 choice of Mustang owners.
Springs
Most of the 30 year old Mustangs have worn out leaf springs in the rear causing them to droop. This is corrected by a new set of springs, and is often upgraded with a set of heavy duty leaf springs with a higher rate in order to make the car handle better. Rear springs are available in 4 leaf, 4 1/2 leaf, and 5 leaf versions, as well as normal, mid, and reverse eye configurations. The mid eye generally lowers the rear 1", and the reverse eye 1 1/2-2".
The rear springs can be complimented by a new set of front springs. An ever popular choice is the Grab-A-Track springs, which are available in both 620lbs and 720lbs rates. Either is much higher than the stock rates, and will lower the front 1", as well as offer less body roll and better handling.
Shocks
If you change the springs out for a stiffer aftermarket set, then you'll need a set of good shocks to compliment them. Not only will the handling be improved, but the ride will be smoothed out quite a bit by a good set of matched shocks and struts. Koni and KYB are two very popular choices for upgrading the first gen shocks.
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