air cooled insert head

 


looks like my insert aircooled head wasnt too off the mark!!..wonder which came first?




this on ebay, pinasco i think, upgrade for scooter engine.

You never know Nigel, your other "one off" modifications may be all the rage aswell!

Kind Regards

Eddie

yeah ill have too keep my "mist cooling" system under wraps....at least till our next meeting..  or maybe my 17mm spanner gear lever mod...   

Not 100% sure for the reason of head inserts? What's the thinking here? Also mist cooling? A bit like water injection?

lots of manufacturers tried water injection, it was on Mick D's NSR on a regular basis, but junked when electronics advanced and took over, I think its a great idea for a bantam especially those with only three gears,! keep us informed how you get on with it and Go for it Nigel.

The head Idea is great for testing different comps/shapes, but I'm not convinced about it, I feel the way its made would be critical to how/if its works in service, but great for experimenting on the dyno or in testing sessions.

regds Derek

Evening Dan,
in the early days of my engine build i had hoped to keep the engine looking like a standard b175 engine and gave the cylinder head to a company, who develope villiers kart engines, to try and get the cylinder head up to modern standards. They kept the head for some time and were unable to help me. So, i noticed that you could buy inserts for some water cooled heads and decided to give that a go and had the b175 aircooled head machined up to allow this kind of set up and had an insert made to my spec. I felt it was the way to go as it would be easier to have any changes to the squish band ect and also having other inserts made to fit without the possibility of ruining a complete head with one slip up on the machining front.

The "mist cooling" is an external set up. Mist can improve cooling of heated surfaces by up to 70% more than air alone. Air cooled engines can lose a significant amount of power (and sieze) as they get hotter and the addition of mist, as and when the temps get high, would help reduce this. If you can catch the steam produced and condense it back to water, you can have hot water for a nice cup of tea when you arrive back into the paddock...  ....everyones a winner:lol!: 

Whilst in Canada I got involved Totonto Research in water injection on a diesel ... Worked well with a T.R.´d instrument called a `hydro-shear´which emulsifired the mixture of 20% water 80% diesel....

There´s plenty of information on different forms of water-injection on the web...

It´s Old Hat, of course, and was used during the war in aircraft for a boost on take off -- just a squirt water into the intake maniifold... Messerschmidt had Direct Injected fuel into the cylindder but I´m not sure if they injected the water that way....

Need´s to be done cleverly otherwise enormously expensive difficulties follow....

Cheers1

Hi ,
I don`t want to rain on any ones parade but for a race bike 2t engine, water injection so far, fails to live up to initial expectations. Sure it works and a lot of extra torque can be produced but the exhaust pipe is so dramatically cooled and takes so long to recover and regain max power, that lap times are slower than without it . Both Honda and Aprilia tried it and eventually junked it , significantly, piston engine fighter air craft used it to great effect, but these engines don`t run a tuned pipe , and run at almost constant revs.
However , what you describe Nigel, sounds intriguingly different , hope it works for you and I look forward to enjoying a cuppa with you !

Cheers, Trevor

Right Trevor!
I must confess we did it to clean up the exhaust for underground mines diesel dumpers not for a boost of power.

A Japanese engineer wrote a long, mathematical treatise on the subject where he claimed reduction in exhaust emissions plus an increase of power.

The aircraft had it for a boost on take-off and definitely used Open-Pipes...

That´s a talking point:   when did resonant pipes hit the scene?  1948 or 1955? Or somewhere between?

Yet I wondered if you squirted a little water in, now and again, what effect that might have a on highly tuned 2-stroke. Particularly into the transfer area where the air-fuel temperature   has been raised by primary compression. Not too much mind...

... perhaps iced toníc water with a dash of gin...

Yaaawwwnnn!