Thanks Troy and Chris for the fill in! Excuse the abbreviated slandering. I got frustrated like a stuck throttle.

Chris, Harleys are not my thing but my cousin has bought these heads after damaging the stock harley heads and it has made his custom hardtail a beast. So far amazing acceleration throughout and much better economy. Before fitting them for him I got them heat proof coated along with jet coating his headers. The latter does make a difference but surely not this much.
The

Benny said - "I would not expect to see any change from 5 - 6K mark."

Am I reading this right - $5,000 to $6,000 per head - US dollars? Or is this an RPM / powerband comment?

That'd be Australian dollars, I'm pretty sure.

On a side not I got a quote from roton (rotary valve maker) for 7-8000 pounds for a one off A series rotary valve head ready to bolt on or bolted on if I supplied the engine and custom pistons. This is a head that increases the flow to almost double the best twin cam heads and has many other advantages like up to 15 to 1 compression ratio or 12 to 1 with low quality fuels.
If this falls through some could contact Roton for the juicy bits.

http://www.rotonusa.com/advantages.html
http://www.rotonusa.com/roton_system.html

read 1-5 its very enthralling.

As mentioned in the website, rotary valve cylinder heads have been around almost since the invention of the infernal combustion engine.
Dunstan Engineering in South Australia made some single shaft versions for the old Holden six cylinder engine in the late 50's & early 60's. I believe that it was the third version that had a front drive that allowed the engine to be used in a car, previous versions being used in boat applications.
They were alleged to be good for 12,000 rpm which is when the rods stretched. [that's about 60mph/100kph in first gear of an old Holden]

A friend in a nearby town has one of these heads but all of the previous efforts, including the Dunstan ones had the same basic problem as the sleve valve engine, the sealing in of combustion gasses & of oil after a relatively short time in service.

If this mob has actually overcome that problem then the days of the poppet valve could well be numbered in new car engines.


Dunstan link

Its a good story about Dunstan, thanks for the links as I forgot his name.

Quote:

a hemi combustion chamber is best used with forced induction. otherwise its hard to get CR high enough without causing problems with gas flow and spark propogation. Its also hard to run big cams to suit NA applications with such a high included valve angle. been through all that with the 2T-G Toyota engines.

This is no ordinary hemi/wedge hybrid, It uses the best of both worlds. I agree with normal hemi designs and boost who wouldnt after those puerto ricans embarrassing the world with little toyota 4 cylinders.

Does anyone has pictures of this remake? I sent Mikko an e-mail asking some pictures of the head, but he didn`t reply yet! Is just for shut the mouth of some unbelivers here in Portugal! Can anyone send me?

Last I heard he is making a new 4 cylinder alloy block copy of halve a Dodge hemi VCT V8 and so he could use the production heads.

I wish