Hi guys, it was brought to my attention that there is a kit available to convert vw polo engines to a hyabusa cylinder head, such motors are often seen in hillclimb cars here in Germany. There are 2 companies that produce the kits, however one has closed down, further research found similar kits available to convert mini engines to a BMW K1000 head. This got me thinking, maybe there is a possibility of fitting a motorcycle head to a daihatsu engine. The GSXR 750 has a similar bore size and pitch as the K3-ve, and when photos of the corresponding head gaskets are overlayed the bores, head bolt pattern, and coolant galleries appear to line up unbelievably well. A GSXR750 head in original form should easily flow 150hp, not to mention the vast array of aftermarket cams, intakes, headers and so on. Second hand heads are available on ebay for as little as 80euros. After investing some thought into the subject I am thinking the k3 timing cover could be easily modified, timing sprockets would be fairly simple to adapt with some lathe work, an older style carby intake could be used leaving the factory daihatsu ecu in place to handle ignition, eliminating the need for an aftermarket ecu. The biggest hurdles would be the larger coolant galleries on the front right corner of the k3 block, and ofcourse oil supply (possibly and external line could be used) and oil return/drainage.
Its definitely a cool idea, but what I dont know is, which direction does a motorcycle engine turn? Does the firing order match or would custom camshafts be needed? And what galleries are for oil supply on the k3 block and gsxr cylinder head?
Hopefully someone could help fill in the missing pieces, and if it looks like it could work I will look at making up a template from the head gasket and checking it against my old motor.