Table of Contents
Advertisement
turns is a 3.55 rear ratio, etc.... The other way to check the ratio out is to open the rear differential up and look
on the ring gear. While the rear is open change the fluid. This never gets done enough on the car.
Changing the gear ratio is one of the least expensive ways to improve your car's performance and it is easiest to
do before assembly, since the rear is out of the car. If you know you are going to change the gears get the 2.73
rear since these are the most readily available, the least expensive and the least abused. All of the gear ratios
work well with our car but we've found that installing an aftermarket 3.55 ratio really wakes the motor up. If
you change the rear end gears, don't forget to recalibrate your speedometer so that the speedometer reads
correctly.
www.Factoryfiveparts.com
EFI Engines
There are three things an engine needs; air, fuel and spark. If you allow more of each of these into the
engine, it will make more power.
Below is information for a pushrod 302 (1987-1995 Mustang) engine.
Throttle Body
Stock 87-93 Mustang size: 58mm
A 65mm throttle body work well up to 350hp. Ford Racing, BBK, Jegs, Summit Racing etc... sell many other
sizes.
Mass Air Meter
Stock 87-93 Mustang size: 55mm
In order to increase the flow of air above 5000 rpm, upgrade from the stock mass air sensor. Aftermarket 70
mm or 75 mm mass air units are an excellent choice and have proven effective. If the mass air meter is changed
make sure it is calibrated for the injectors you are using or you will have to change the injectors too. Pro-M or
Ford Motorsport meters work the best. Usually the mass air meter is larger than the throttle body.
Fuel Injectors
Stock 87-93 Mustang size: 19lb/hr.
The stock injectors are good for exactly that, a stock engine. If upgrading parts, step up to 24 lb/hr injectors.
They are good up to about 400hp. Make sure that you have the mass air sensor calibrated to the injectors you
use.
Upper Intake
The next logical step for breathing is a more free flowing intake manifold. There are a number of intakes
available from different companies (e.g. Edelbrock, Trick Flow). Ford also makes a good intake, the cast 1993
Cobra intake from Ford Racing.
has brand new 8.8" solid ales available with 3.55 gears.
www.factoryfive.com
529
508-291-3443
Advertisement
Table of Contents
