New MED 1275 cylinder head castings now available

New to MED, brand new A-Series head castings are available now as a DIY kit or a fully-modified and assembled unit, ready to bolt on. 

Our supply of original 12G940 castings began to dry up four or five years ago, around the time we moved our workshop from Hinckley to Lutterworth.

A once-vast collection of 1275 used cylinder head castings had been gradually depleted, as many overseas customers didn't have a donor casting to send in, or the shipping was uneconomical. 

With usable castings becoming more difficult to find, the price has also been gradually creeping up. 

Factor in damage or cracks from previous mishaps, and we'd often find that even the best looking donor castings were not suitable for modification. Sometimes we'd discover cracks after two or three days of machining, which could be especially frustrating...!

So moving forward, it was inevitable that a new casting would eventually be required if we wished to continue producing our popular MED modified heads. We've modified several thousand cylinder heads since the 1980s, for both fast road and race applications.There's two main advantages to the new castings - no coolant has ever pumped through the water jacket, so no corrosion, and we have them cast with performance in mind, so there's far less machining required to increase flow.

Once cast, the heads are actually CNC machined rather than modified by hand, with hardened exhaust valve seats installed and the valve seats initially cut with a three-angle design to match our 21NS stainless steel race valves. 
As you can see above, the ports are already accurately CNC machined out to a larger diameter, designed to match our 'standard' size inlet and exhaust manifold gasket, part number MED-1914-SG. These are based around a 36mm diameter inlet port and 30x26mm exhaust.

The inlet ports are machined out to the largest recommended size, still giving good clearance to the pushrod bores either side. You can also see from the image above that we no longer have the excess material around the valve guide bosses that can be so laborious (but essential) to remove when modifying a standard head.  Here is a fully assembled cylinder head. Note that the chambers are also CNC machined the same in both volume and shape, the valves are seated perfectly level to give equally consistent valve spring pressure, and the extra two '11-stud' holes pre-drilled.  

We even have our logo cast in to the top face of the head so you know it's one of ours!

  If you are keen to build up a cylinder head yourself, we can also offer a MED Road Competition Kit, as in the picture above. This comes with all of the components required, but with a cost saving on the labour involved. The cylinder head ports come supplied with a bare cast finish, apart from the final 40mm which is CNC'd, so will need to be carefully polished by hand to improve flow.

The valve guides will also need to be installed, bored to size and the valve seats finally cut to perfectly match the valves.  

Including a final reface of the head, our machinist typically takes around five hours to transform a kit to a completed assembly. Then perhaps a coat of paint...!

Both options are listed now on our five-port cylinder head page.