The original Special Tuning head 8 port head by Jim Whitehouse is the ULTIMATE Push rod head for the "A"Series has now been revamped and made available with larger inlet valves and special seats available to special order.Ports and combustion chambers are CNC machined and ready to use.Annealed befoer machining and pressure tested after build before sold.
Fitted with
C-AEA530 titanium top caps
It is supplied fully assembled with springs/top caps,Evo collets and uses larger 37mm inlet valves and 30.5 exhaust valves and will handle cam lifts up to .500"
Also in this kit is a set of correct length (.220"longer) push rods C-AEG583,plus the 4 front head studs
51K282 and manifold gasket
C-AHT380.
Standard S con rods Number 2 and 4 usually need modification for clearance owing to cam lobe configuration. Con rods ready to fit are available as C-AEG624.
Special 8 port cams are required. Special exhaust manifold
C-AHT343 is also required.
Combustion chamber is approx 20.5cc (compression ratio should be checked) to suit sensible compression ratios on big bore engines and from Jan 2012 the revamped head uses stepped guides which retain the valve spring platform as per all modern day race heads.
A special set of 8 port hilift roller rockers in correct sequence and spacings are also available as
C-AHT448 for this new head.
A fully programmable injection management kit is available as C-AJJ4065
Head Gasket GEG300,BK450 or
C-AHT189 Cometic type must be used
cylinder head nut torque setting is 50ftlbs, if using a Cometic type gasket the head must be relieved to clear the rivet on the gasket.