Kelford camshafts, Ford Coyote 5.0, GT350/GT500-heads

Kelford camshafts, Ford Coyote 5.0, GT350/GT500-heads

Kelford is a New Zealand camshaft manufacturer with roots in Christchurch dating back to 1968. Its profiles range from upgrades for street-driven cars to fully built race engines. Choose the cam around the rest of the engine and its intended use, rather than simply picking the longest duration.

This selection is for the Ford Coyote 5.0, GT350/GT500-heads engine. Profile differences, spring recommendations and required modifications are detailed below.

Technical specifications – available profiles for this engine

Profile GT-256-A

Stage 1 naturally aspirated profile for a 5.0-litre Coyote block with GT350/GT500 heads and the Coyote firing order. For a street car with an upgraded exhaust and ECU tuning, working to approximately 8500 rpm. Requires KVS257 springs and aftermarket pistons with deep valve pockets. Stock pistons are unsuitable.

Manufacturer profile information

Profile GT-256-B

Stage 2 naturally aspirated race profile for a 5.0-litre Coyote block with GT350/GT500 heads and the Coyote firing order. Suits a free-flowing exhaust and an upgraded intake such as individual throttle bodies. Works to approximately 9200 rpm. Requires aftermarket pistons with suitable valve pockets. Retains variable cam timing.

Manufacturer profile information

Profile GT-256-C

Stage 3 naturally aspirated race profile for a 5.0-litre Coyote block with GT350/GT500 heads and the Coyote firing order. Requires ported heads, high compression and a free-flowing intake and exhaust. Works to approximately 10200 rpm. Requires aftermarket pistons with deep valve pockets and KVS257 springs. Kelford recommends fixed cam timing.

Manufacturer profile information

Profile GT-256-TA

Stage 1 turbo profile for a 5.0-litre Coyote block with GT350/GT500 heads and the Coyote firing order. For around 1000–1700 hp with twin 54–62 mm turbos, working to approximately 8500 rpm. Compatible with stock pistons at the specified cam timing, but piston-to-valve clearance must be checked. Requires KVS257 springs. Kelford reports approximately 10–15% more power than stock cams, depending on the engine and tuning.

Manufacturer profile information

Profile GT-256-TB

Stage 2 drag profile for a 5.0-litre Coyote block with GT350/GT500 heads and the Coyote firing order. For around 1700–2400 hp with twin 64–75 mm turbos in seven-to-eight-second quarter-mile cars. Works to approximately 9200 rpm and retains variable cam timing. Requires aftermarket pistons with deep valve pockets and KVS257 springs.

Manufacturer profile information

Checking heights are shown with the duration figures. Net lift is the net valve movement specified by the manufacturer, while cam lift is listed separately. IVO/IVC denote intake valve opening/closing and EVO/EVC exhaust valve opening/closing. BTDC/ATDC mean before/after top dead centre, and BBDC/ABDC before/after bottom dead centre.

Installation and profile selection

Confirm the exact engine version, valvetrain design and the modifications required by the profile. Check cam timing and valve-to-piston clearance during installation. Springs, lifters and other supporting parts mentioned with a profile are not included unless the profile explicitly states that they come with the kit.

Examples of related vehicle applications

• Ford Mustang / F-150 5.0 Coyote -builds with GT350/GT500 heads and the Coyote firing order

The list covers versions with the specified engines only. Exact fitment and required modifications depend on the selected profile, cylinder head, lifters and timing system.

Kelford Cams