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LOTUS/QED TWINCAM CYLINDER HEAD - 1991 MODEL

Lotus cars and QED have combined forces to reproduce the ‘Sixties favourite cylinder head’. Cosmetically identical to the last of the original equipment units (ie 1967-1974). Europa versions are also available. The availability of new castings allows us to offer our customers specifically modified heads in various stages of assembly.

QED SPRINT SPECIAL CYLINDER HEAD
This is our first uprate option using a fairly soft, standard lift camshaft with standard blueprinted springs. This unit gives 135+BHP at 6500rpm with 112-114 ft/lb torque at 5250rpm.
Option 1- New cylinder head complete with cam caps and all studs. Gas flowed ports, matched chambers, specified compression ratio, fitted with colsibro valve guides and heavy duty seat inserts machined to accept 1.325 exhaust valves and 1.565 inlet valves. Inlet seats radiussed and blended. Complete with valves.
Option 2- Cylinder head as option 1, but complete with kit of parts to enable customer to complete. Comprising additionally, valve collets and spring base plates, standard, blueprinted valve springs, retainers, pair of Q360 camshafts, cam bearings, cam followers, a selection of shims, assembly compound and data sheet.
Option 3- As option 2, but fully assembled, shimmed, painted and ready to fit.

QED ROADSPRINT CYLINDER HEAD
This engine is specifically produced for people with Sevens, 23B’s, etc who require a powerful but street useable engine. (Also very popular with Elan and Europa owners) utilizing our well-tried and proven Q420 camshafts, this unit gives 145-150 BHP below 7000 RPM with 118-120 ft/lb torque at 5000 RPM.
Option 1- New cylinder head complete with cam caps and all studs. Gas flowed ports, matched chambers, specified compression ratio, fitted with colsibro valve guides and heavy duty seat inserts machined to accept 1.325 exhaust valves and 1.565 inlet valves. Inlet seats radiussed and blended. Complete with valves.
Option 2- Cylinder head as option 1, but complete with kit of parts to enable customer to complete. Comprising additionally, valve collets and spring base plates, Q55 valve springs and retainers, pair of Q420 camshafts, cam bearings, cam followers, a selection of shims, assembly compound and data sheet.
Option 3- As option 2, but fully assembled, shimmed, painted and ready to fit.

QED RACE HEAD
Option 1- Fully machined head casting less seats and guides. Ports as cast for modification. Available only to recognised engine builders.
Option 2- Fully built up race head fitted with, typically, 1.4 exhaust valves and 1.625 inlet valves running in extra length bronze guides, seating on oversize seat inserts (aluminium bronze inlet, high chrome/nickel alloy exhaust). Lightweight steel spring retainers and collets on our own specification springs. Thin wall lightweight alloy steel heat treated cam followers. New steel billet camshafts. Inlet tracts opened out to accept 45mm carbs, with a compression ratio to suit.