OPTION: In FIG 3 you may notice a large area at the rear of the head has also been welded. This is done so the use of a standard BK450 'A' series head gasket can be used.

This extra welding is not required if using our special made Cometic twincam conversion head gasket.

 

Unit D, Scotlands ind est, Coalville, Leicestershire, LE67 3JJ   TEL:+ 44 (0) 1530 830369    FAX:+ 44 (0) 1530 833171

FIG 2: CYLINDER HEAD FRONT SEAL PLATE

FIG 4: CYLINDER HEAD RE-SURFACED

 

 

Build guide page 2:

FIG 1: STEP PLATE WELDED INTO PLACE

FIG 3: OIL DRAINS DRILLED & TAPPED 3/8 BSP

Welcome to Morspeed performance tuning

CYLINDER HEAD CONVERSION

The step plate has to be alloy welded into the cylinder head FIG 1, the original BMW head design used a chain to drive the camshafts, the chain was run through oil for lubrication, this is now blanked off by the step plate allowing the use of an external dry belt to drive the camshafts. once the step plate is welded into place the 'over hang' will need machining flush with the original head front face. When the front plate supplied in the conversion kit is fitted FIG 2, it will now give an oil tight seal.

 

 

 

 

 

 

 

 

 

The cylinder head is force fed with oil to lubricate the camshaft journals & buckets through a small hole, this oil hole needs to be blanked and re-drilled to match the oil feed hole in the 'A' series block, this is a simple operation wich requires moving the hole over by only a fraction and then drilling at an angle so as to break into the original oil feed channel. Oil needs to drain back from the head into the engine block as fast as possible otherwise the cylinder head will simply just fill up! this is achieved by making oil return drains, the head already has 2 large return drains but these need to be blanked and re-drilled then tapped to accommodate pipe fittings. We use 3/8 BSP. FIG 3

RETURN TO HOMEPAGE

Once the required step plate has been welded into place and the oil return drains drilled and tapped the cylinder head will need to be re-surface to ensure a perfectly flat head gasket seal, it would also be a good idea at this point to work out how much capacity is needed in the combustion chambers depending on the compression ratio you intend to run. FIG 4 on this build we required 20.0cc in each chamber.

Now all that is required is the cylinder head to be re-assembled with its valves and springs.