Designed for Ford Parts.

Engines:

In the early days most challenge car were built with spec Mustang running gear (engines/trans/rears).  Nowadays with the proliferation of not only spec legal series cars, but monster open track customs, we can only tell you what fits 9with respect to engines etc)… we can’t tell you what to use!

Whether you are racing in the FFR-NASA Challenge seires or running an open class racer, you still have to select an engine and transmission to use with this car.  We’ve built cars for our racing programs using the full range of Ford small-block and big-block engines.  The aftermarket is alive with parts and services related to this category.  Additionally, today’s modern running gear provides reliable performance for less money.

It’s important when taking on this project to decide on an engine and transmission configuration that will deliver the power you need and is within your budget.  The challenge kit, like the Mk3 roadster is set-up to use the full line of Ford engines. 

You can easily install an original 289, a mustang 302, the popular and torquey 351 Windsor engine, the old 390/427 FE engines, the newer 429/460/514 crate motors, and the 4.6L SOHC and DOHC engines.  We have not had good luck with the 4.6 engines on the track and have found that 350 hp small blocks usually strike the best balance. 

Transmissions

The challenge kit is ready to accept the full line of Ford and many aftermarket transmissions.  While there is plenty of room in the transmission tunnel for older set-ups, we still prefer sticking with the newer running gear for affordability and durability. The stock Mustang transmission is either a T-5, T-45 or 3650.  We have run T-5’s in our race cars for years with excellent results.  Most racers choose the Tremec TKO transmission and upgraded heavy duty Ford Racing clutch.

Rear Ends and Gearing

The FFR three-link suspension requires that you buy an 8.8” solid axle rear end.  1987-2004 Mustang GT’s were equipped with a few different gear ratios.  The majority of the cars have a 2.73 ratio.  There were optional performance rears that used a 3.08 ratio and many cars were built with automatic transmissions and a fun 3.27 ratio. Keeping in mind that the T-5 is an overdrive transmission, you have some space to improve the gear ratio with aftermarket parts without compromising the street manners of the car.  The most common gear sets used on the track are 3.27’s.

Intake:  Fuel Injection vs. Carbureted

Before building the car you have to decide whether you’ll be using fuel injection or carbureted systems.  The EFI stuff on the Mustang works great.  You can use either the Mustang donor wiring harness and computer (for EFI set-up cars) or an optional aftermarket harness that we can provide with the kit (replaces the EFI stuff). 

If you are going to use the Ford computer/EFI stuff from the Mustang we’ll give you everything you need to make it work.  The EFI kit provides a new air filter set-up for the mass air meter, an alternate drive pulley assembly to accommodate the air pump and custom length fan belt.  Our assembly manual helps you figure out where to splice in the lights, signals and other electronics.  Pulling a wiring harness and computer from your donor car can be tricky so we walk you through that as well and we also offer factory new harnesses for those less brave souls.

Headers and Exhaust Parts

The kit exhaust parts are assembled and ready to bolt on, with all fasteners and gaskets.  The standard kit comes with the side exhaust assembly which includes a pair of straight tubes, the dual side exhaust units, and the fasteners/gaskets needed.   The side exhaust matches the look of original vintage cars.  The entire assembly bolts directly onto the stock Mustang exhaust headers in front and onto rubber isolated mounts in the back.