Aluminium & Iron Cylinder Heads - TR3-4A

High Port Cylinder Heads

These brand new cylinder heads are designed, as closely as possible, to resemble the original, late, TR4/4A units. All fully machined cylinder heads are supplied with lead-free compatible valves & valve seats as appropriate, all core plugs and push rod tubes are fitted. If higher compression ratios are required, up to 0.150” may be safely removed from the head face. Note: We recommend you use all new hardware, and use uprated components for uprated engines.

Plain cylinder heads This is the plain spec to allow maximum flexibility if serious modifications are planned. The head is supplied with the basic machining work done, but without valve guides or valve seats. Push rod tubes are installed and hardened valve spring seating washers are supplied with alloy heads. (Part nos. 511695X & 511695AX)

Standard bare cylinder heads Machined cylinder head to suit standard valves. Valve guides are fitted and reamed to take standard stem valves.  Valve seats cut ready for standard size valves, this spec cannot be re-machined for larger valves. Push rod tubes are installed and hardened valve spring seating washers are supplied with alloy heads. Requires final assembly.  (Part nos. 511695 & 511695A)

Standard loaded cylinder heads Fully machined and assembled, ready to fit. This spec cylinder head is standard size with lead-free compatible valves. (Part nos. 514748 & 514748A)

Modified Cylinder Heads

Our range of gas flowed heads are available to suit all needs. On some heads the work is carried out to the customers' own unit, the more popular heads may be available on an exchange basis. All heads are supplied with stainless valves, bronze-alloy valve guides and valve seats suitable for unleaded petrol unless requested otherwise. These cylinder head specifications are based on a 9.5:1 compression ratio on an 87mm engine. Please advise us of the engine capacity and any planned changes when ordering.

 Stage II cylinder heads – uprated road Modifications include gas flowed ports and reshaped combustion chambers. New standard diameter valves are reshaped  and fitted with new guides and uprated spring valves. (Part nos. TT1112, TT1112N & TT1112NA)

Stage III cylinder heads – fast road/competition Further modifications to the ports and chambers. Large inlet valves are fitted with new guides, uprated valve springs and alloy valve caps. (Part Nos. TT1113BUL, TT1113N & TT1113NA)

Stage IV cylinder heads – competition Fully gas flowed and ported to competition spec. Large inlet & exhaust valves fitted with bronze valve guides, uprated valve springs and alloy valve caps. This spec is only available on new castings. (Part nos. TT1124N)

For detailed specifications please call your local Moss branch.