NineMeister

Oh, OK, this was not clear from your initial question. Obviously I haven't got a clue what your Yanmar diesel looks like, but my view would be the same for any engine development project in that you should have a long hard look at the piston first with a view to making it as light as possible. Once all avenues here have been progressed, including exotic materials like MMC (which is stronger than 2618 so you can make the part with thinner sections) you could then look at the pin material to make a saving. However, on the assumption that your piston is not currently ideal, a regular high grade carbon steel pin will do the job nicely enough whilst also having greater fatigue strength and longer working life than the DLC coated Ti pin.

Incidentally, the machine shop I work with already make ti & steel pins for a lot of superbike teams as well as F1, one of the clever options they use are non-parallel bores for the steel pins to remove material from lower stress sections of the pin and can hence save another 25-30% from the total weight without compromising the strength and life of the part.

Indycam

http://images.google.com/images?q=ya...N&hl=en&tab=wi


I'm gunna have the baddest yanmar in the harbor !

Stock its only 5.5 hp ,
I wanna pump it up to at least 6 .

CWay27

How could he misunderstood you if your original post doesn't mention anything about yanmar engine?? They're talking about a 4.0L project and you jump in with carbon coated rod for diesel engine......... Was it a joke??

NineMeister

Sure looks like it....

Indycam

I asked a person who I trust , a general question about an item .
He gave an excellent answer .
I made a joke .
He gave another excellent answer .
I joked around some more .
You posted .

The Good info is in Colin's posts .

NineMeister

Don't fret, no offence seen or taken; in any case, I'm always happy to play fantasy engine tuning with other like-minded petrolheads, otherwise I wouldn't be here.

Indycam

Cool , the pin you talked about , "non-parallel bores" , the "gun bore" is offset to one edge ?

NineMeister

No, the pin is symetrical about the centreline, the outside is obviously parallel but the bore is profiled (undercut), the aim is to even out the bending stresses through the section of the material, but you will need a CAE design package to deduce the actual profile required.

forklift

forklift

"lets see, if I had an extra $x,xxx.xx I would buy x and get x bhp and drop my lap times by x seconds"

Now about that $x,xxx.xx....

NineMeister

Life would be sooooo dull if you did not have the odd fantasy that with (usually huge) effort you could change into a reality. Bring on the dreamers, join the club now!