Hi Tim,
Great progress on the new engine. Looks great and I truely want to hear it run. It will be great if we can do a 6 cylinder MOD fest one day. Be so good to hear a bunch on the water again.
Alan
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Hi Tim,
Great progress on the new engine. Looks great and I truely want to hear it run. It will be great if we can do a 6 cylinder MOD fest one day. Be so good to hear a bunch on the water again.
Alan
Thanks for your support.... Plan on an event next year. Possible boats are Van Weele, Kurcz, Welch, Austin (as many as 4 boats), Brill/Weinert (rumor is they just bought the Dunn rig) and others. That's a minimum of 5 so far.
Others with a stock, mod, or alky Merc 60 or 66 cubic inch six interested to run a special event please respond. Hydros for sure, perhaps runabouts too. Let's get a roll call going.
Tim
If all goes well obver the winter I plan on restoring my Jerry Waldman Sid. Doug Kay is finishing up my two 75-H engines so might also bring that to run with our MOD engine.
Alan
Here, aluminum screws are installed with Loctite 271 (high strength). Loctite is dripped into the holes and the screws driven slowly to extrude the liquid into the threads by hydraulic pressure, assuring complete thread fill.
Once cured, most of the screw will be milled away along with the angled portion of the reed cage. This leaves a solid flat flange surface into which re-located mounting holes will be drilled and tapped in the newly modified pyramid reed block.
Is there a secret formula to determine reed area versus cylinder capacity
There is no formula that I know of as pertains to displacement. There are five metrics that I use: 1) Combined port width at the apex. and 2) Combined effective reed area (outer 2/3 of reed). 3) Ratio of duct volume consumed to either of the above. 4) What will reasonably fit the duct without affecting ccase compression, and 5) What do the racing rules say: Are there any limitations or prohibitions?
Observations are that later model cages have steeper angles than earlier designs. This may have been be more related to packaging than flow capability. Also, engines accelerate better more with more reed area. My thinking is greater area allows reeds to respond more quickly even though top end performance is little affected.
Unless you work research with a flow bench (or dyno) and have a penchant for wringing the most out of your project, you're better off scouring the SAE database for tech papers on the subject. This is most certainly a well researced topic.
Tim
PS If any of you have a formula and care to share, please save us all some time & $$$.
I have a few SAE papers from a couple of Japanese guys on various things that are very good reading but not focused on reeds.
The angle is interesting I think OMC has some documentation on red angle re low speed and high speed differences
I have one on reed simulation that is in the public domain, I will dig it up.
I have always tried to find data on the 500cc GP bike engines but that clearly is locked away
Cheers
EDIT Found it
Attachment 49901Attachment 49902Attachment 49903Attachment 49904
Is this the simulation you refered to? A brief review proves the tools interesting.
http://www.torqsoft.net/reed-petal-design.html
The power of the internet for research is fantastic! The fact is engine architecture, packaging, and economics throttle unbridled design.
Anyway, here is the latest progress. The hardest part is done!
Hi Tim,
Engine is really getting there fast. At the rate your moving you will be running it in 4 weeks. Your making so many chips that you could sell bags of them to help with the cost of creating the work of art.
Alan