Cylinder head

[Bill Sheehan]

I've never had a problem with the 37 head. My blown car runs a 37 head (with a lowered CR) and doesn't oil plugs despite having two stroke in the fuel. That said I do have a nice fat spark created by a properly rebuilt ML magneto - the higher you rev, the bigger the spark.(which tends to be the other way round with new fangled coil systems)

I've only ever had one engine that oiled it's plugs with a 37 head. It was built years ago and had a slightly slack re-bore from the start. It did do a zillion miles much of it in competition. Malcolm borrowed it when he was building his Ulster and I fitted a L/C head before he took it away. It still burnt oil but it didn't oil its plugs. We always referred to it as 'Old Smokey'. It's still on the floor in my garage - I might even re-build it one day.

I imagine Charles' engine is bored properly and doesn't burn much oil if any at all. His re-built magneto will probably overcome most things! Whilst I don't criticise anyone who uses electronic ignition, those that know me will understand it when I say I'd rather poke my eye out than use such a thing myself!

Steve

In all these years I haven't heard of plug-oiling problems with the '37 head until now, but would suggest it's subject to the condition of the rest of the goodies.  I was convinced of the difference from an early head back in the mid-Seventies when visiting Barry Risely in a Hobart suburb during a two-week tour of the Island..  As there aren't many places where you can accurately check your oil in Tassie (!), I was not surprised to find the top of his house was level with the street.  He entered his block via the next street below.  He doubted I could get up onto the rear parking level in my '25 Chummy and he was correct - I got half way, not helped by the ruts and waterways on the steep surface.  His '29 Chummy was in good condition and he told me he also could not get up the rise until he fitted a '37 head (& nothing else).  He sailed up with ease every time.  As one who always believes in what actually happens rather than rely on theory alone, I was convinced of the value of the later head, and I know many who still are.  Even a small increase in Neddies surely must be helpful?   Cheers,  Bill