... Every piston I have ever seen from Diamond has been "monstrously" heavy. I am currently trying to get one of my vintage clients to change from Diamond to JE... The Diamonds are cheap though...
Sorry to dig so far back into this thread. But in general I respect what FordBoy posts; which left me very puzzled by this response to my selection of Diamond for custom billet pistons. Reading tonight about Dutweiler's continued use of Diamond pistons in Speed Demon engines reminded me of this puzzling statement. Was FordBoy being sarcastic? If not, I'll try some sarcasm of my own- maybe he should try to get Kenny to "change from Diamond to JE". 
Thanks Jack, for calling me out on this. An apology and an explanation are in order.
No sarcasm was intended in my comment. However, in retrospect, my use of the adjective, "monstrously", was way too negative and inaccurate. Diamond has been around for a long time, has a wealth of knowledge about piston manufacturing, and produces a great product many use and endorse. I certainly apologize for any perceived slight to them or their reputation.
AND, far be it from me to tell Ken Dutweiler how to do anything. His record stands on its' own.
Let's talk about pistons though, while recognizing that everyone's experience with various manufacturers is going to be different. Why is that?
Some reality about pistons is that the mass of the piston, (and the piston assembly), has a vital influence on how the piston performs. IF, as in the example offered, the Dutweiler built turbo engines for Speed Demon, the need is for high temperature strength and the ability to shed that heat from the mass of the piston, that particular piston will probably need greater section thickness, even with oil jet piston cooling. And, therefore, that piston will be heavier than a piston for a normally aspirated engine of the same displacement. So for a normally aspirated application it would probably be "too" heavy.
That is my point about the other example, my client with a normally aspirated MGB. The Diamond produced piston is quite a bit heavier than it could be, for that bore diameter. Why so? Not every piston manufacturer has a "light weight" forging for every bore diameter. Some manufacturers do not have even standard style forging blanks for every bore diameter. Why? Because forging dies are an expensive cost, and if there are very few sales for a given bore size, it is simply a poor business choice to have a die, or multiple dies, for an application that loses revenue. The Diamond piston is just "heavier", and the client has had some component failures. A lighter piston would reduce the component stresses and reduce the failure rate. Not every manufacturer can produce a "lighter" piston assembly for the application. MG's are not as popular as a race engine platform as the small block chevy. Stands to reason, and that is why there are more manufacturers producing more choices for chevy engines.
In the last 20/25 years, one of the goals has been to increase bhp output by increasing the rev limit. Lighter components are the reliable pathway to increased rpm's. I have used lots of JE pistons over the years and have always been satisfied. The caveat is that for the most part, they were for smaller (less than 3.5" bore) bore diameters. And they were not the lightest pistons. Usually Cosworth pistons were lightest, and not always available. Availability, or lack thereof, causes a search for an alternate manufacturer.
And since this current permutation of the Milwaukee Midget is going to be normally aspirated, AND have a higher working rpm limit, (and that does not account for 5' 17" sized feet . . . . . .
) the smart choice is to go with the "lighter" type piston assembly. Supplier to be determined, but Wossner has a forging to suit the application.
Disclaimer: This is my opinion, and my opinion only. My opinion is influenced by my personal experience, and the experiences of others in the industry whose experience and opinion I trust and value. I reserve the right to change my opinion at any time, without any notice. I'm kinda fickle that way . . . . . . .
AND, it is also important to note that there is always, "some disagreement", between professionals in the industry, about what is or is not, important. Only the end user can determine if a part is adequate for the intended application. And that is usually determined by destructive testing . . . . . . . . Da**!! I hate when that happens to my guys.
Fordboy
Topic: Milwaukee Midget (Read 3576969 times)