Engine recipe: the Duratec 2.5L track build, part by part

The 2.5L Duratec is a favorite for a reason. Here is how we would put one together from our own catalog, from the block up.

A recipe is a list of ingredients and the order you put them in. This one is for a Duratec 2.5L built for the track. Pick your compression, pick your cam, and let us help with the details.

1. The foundation

• Skip the building and start with a finished 2493cc 2.5L Duratec shortblock, or
• start from a bare 2.5L Duratec block and build it your way.

2. Pistons and rods

Our 2.5L Duratec long rod and piston kit comes in five compression ratios: 9.5:1, 10.5:1, 12:1, 13.5:1 and 14.5:1. Pick the one that matches your fuel and your class.

3. Bearings and fasteners

• King race series main bearings and rod bearings.
• ARP main stud kit and ARP 8740 head stud kit.
• Esslinger-spec Cometic head gaskets.

4. The head and the valvetrain

• Cylinder head: the Pro Series big-valve head, or the Pro Series turbo head if you are running boost.
• Valves: flat face intake and flat face exhaust valves. Our flat face valves reduce chamber volume about 1cc, which helps high compression builds.
• Pro-Series dual valve spring kit.

5. The cams

Esslinger Pro-Series Duratec cam sets come in Stage 4, Stage 5 and Stage 6, plus a turbo cam set. Solid cams need the right 31mm cam buckets.

6. Set the timing right

Use the cam and crank timing tool set and check it twice.