The EC Big Valve Tillotson JT-207 Cylinder Head with 32mm Intake and 27mm Exhaust Valves with 5mm valve stems.
The Head Comes with 32mm Intake and 27mm Exhaust Valves; 5mm Stems. Precision Multi-Angle Job, Valve Bowl area, cleaned up match to the seats. The valve work is performed on Rotter Seat & Guide Machine for accuracy and precision. Heads are vacuum checked after the valves are installed to ensure your air-fuel mixture and combustion happens in the cylinder.
The Heads Milled to ~18cc Combustion Chamber to increase compression. The intake and exhaust runners are not ported to allow the engine builder or assembler to build the ports to their specifications.
EC offers CNC ported heads for those that need a fast setup out of the box. Springs, Retainers, Rockers, Gaskets, Seals, or valve covers are omitted.
Head Specs:
Intake: 32mm, 5mm
Exhaust: 27mm, 5mm
Combustion Chamber: 18cc, Non-Hemi
Multi-Angle Valve Job
Compression Ratio Examples(Final Result will vary on Engine Measurements):
Predator Hemi, Flat Top, .035" Deck height,
w/.045" Thick Head Gasket 9.22:1
w/.010" Thin Head Gasket 10.48
Tillotson 212, Flat Top, .000" Deck height,
w/.045" Thick Head Gasket 10.48:1
w/.010" Thin Head Gasket 12.19:1
Tillotson 225, Flat Top, .000" Deck height,
w/.045" Thick Head Gasket 10.87:1
w/.032" EC Copper Head Gasket 11.49:1
EC 228R, Flat Top, .000" Deck height,
w/.045" Thick Head Gasket 11:01:1
w/.032" EC Copper Head Gasket 11.63:1
EC 236R, Flat Top, .000" Deck height,
w/.045" Thick Head Gasket 11:37:1
w/.032" EC Copper Head Gasket 12.01:1