Factory Five Racing Mk3 Roadster, Assembly Manual

Page: 190 / 277

190
www.factoryfive.com 508-291-3443
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 Motorsport division.
Heads
The 5.0 Mustang aftermarket is full of aluminum and cast iron heads for the small block Ford. Our
favorites are the
Edelbrock Victor Jr. and the AFR aluminum heads. These both flow very well, have
stock exhaust port heights which allows the use of our headers and not only give you extra horsepower
but also remove 50 lbs. in the process.
Cams
If you need to pass emissions testing, use a cam with a CARB number. We like the Ford E303 cam. We
have used it with success in our racecars both naturally aspirated and in boosted applications. If building
a more radical engine, match the cam to the combination.
Headers
Stock: 1½” OD
We’ve found that the Mustang factory headers work well for the stock engine. If you want to go to an
aftermarket set, the 1
⅝
” MAC shorty unequal length headers or Ford Motorsport 1 ⅝ ” unequal length
headers fit as bolt on parts. They will reward you with an approximate 5-10 hp bump in the top end. All
aftermarket headers use mandrel (smooth consistent bends) bent tubing. The stock ones are not and are
restrictive on non-stock engines.
If using a 351W engine there are two options, use 351W engine swap headers from Ford Motorsport (M-
9430-A58) or MAC (E358692) or if smog/catalytic converters are not necessary, use our full length 4 into
4 headers.
Timing
Most computer chips simply change the timing of the engine and slightly enrich the mixture. Using a
timing light, advancing the base timing to 14
°
will do the same. Higher octane fuel will be needed.
Under-drive Pulleys
Yes. They work well on all cars.
Oil Cooler
Not really necessary on small blocks or cars that aren’t raced heavily. They look nice when installed in
the smaller opening below the radiator opening. For supercharged/turbocharged or big block track cars
an oil cooler will help.
Factory Five offers an oil cooler with #8 Stainless Steel braided lines and mounting bracket for small