- Joined
- Dec 11, 2020
- Messages
- 614
The Zimmerman rotary intake valve is superior. Full circle banded crankshaft would ice the cake for power and compliment the Zimmerman style valve.
Hi Terry, I found a few of your famous titanium/needle bearing rods a while back for a Rossi R65 marine engine. Need to install it. I'm amazed by the very minimal dimensions of these rods. I have to ask, have you ever experienced a structural failure ever ?We made a 45 size Ti rod years ago with 1 mm rollers
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Hi Terry, I found a few of your famous titanium/needle bearing rods a while back for a Rossi R65 marine engine. Need to install it. I'm amazed by the very minimal dimensions of these rods. I have to ask, have you ever experienced a structural failure ever ?
exactly, I-beam shape would function just fine.I can't remember any actually coming apart but we did get some back that bent with hydraulic.
Today I'd make them I beam shaped and not worry as much about the weight...
Thanks, a lot of work has already been done and we hope to have some production engines available in the next 6-8 monthsWell he chose a good engine size to work with. Since from what I'm hearing there are outlawing 20 and 30% nitro car fuel. 60% in a little motor like this will make it fly. The Zimmerman disc is a really good choice as well. Is that motor going to show up this year Hope so. Thanks for expanding the hobby
This is great news. I hope you will succeed in your ambitious plan:
-In Europe some nations have limeted sale, distribution and storage of high nitro content fuel. Some to a previous standard of 25% and now further down to 16% - in accordance with EU legislation to be enforced by member nations.
- Will your design address the challenge of only low nitro fuels commercially available ?
Or
- Will the design only cater for those few diehard racers that will apply for and be accepted to go beyond the law?
Congratulations Mr. Ricky....we need some new ideas and energy in our sport.
Do not let the nay sayers and so called experts discourage you.
Good luck with your new endeavor.
Charles
Look like A-90 Russia but sadly owner business passed away Same your Optima 21? Will be believe more powerful than CMB or NR
Thanks Brad - I think I may have an old Picco that comes with 2 head buttons. The community came forward and has given me plenty of information on combustion chambers so we have plenty to work from now.In the 1990's Picco's came with 2 head buttons foe low or high nitro fuel. There has been a couple of posts on squish bands and volumes and bowls.
Brad
Hi Allan,Look like A-90 Russia but sadly owner business passed away Same your Optima 21? Will be believe more powerful than CMB or NR
Thanks for your support.
Re Fuel composition - This is something that I have been looking at as I generally run tethered hydros and we use straight fuel with zero nitro, just 20% castor, and the rest is methanol so I have been discussing with Profi about different combustion chamber shapes and volumes depending on the application.
As far as I can ascertain, no manufacturer produces an engine designed to be used with nitro percentages as high as 60%. They often come shimmed for around 25% nitro and people will modify the combustion chamber volume for their specific needs.
We will test a few different combustion chamber shapes and volumes to see what works best with different fuels but it would be interesting to hear what people have done to adjust their commercially available engines to suit nitro contents around 60%, Can anyone share their combustion chamber volumes and/or squish clearances, it would give us a head start on development?
Once we have completed the testing we will be able to make recommendations for what combustion chamber to use and what volume/squish clearance we have found works best. This will give most users a starting point to adjust their engines from.
I wouldn’t worry about needle bottom ends at all on a .21. I have not seen needle bottom ends on a .21 CMB in many moons either. I’m not aware of the new CMB Beta .21 having them either. I have a bronze bushed rod in a Nova .46 that has raced now for 4 years and it’s not out of spec. Fast engine that I’ve ran hard at times. Jeff LutzThanks Terry, now you know why i have been so interested in your dyno project.
re needle roller rod bearings, we did look at it but it proved difficult if not impossible to fit this within a standard .21 bolt pattern. Then there are more issues related to the balance ratio with the rotating assembly. Im not saying it’s impossible but the amount of development required is just too much for our first engine.
As an alternative we are looking at DLC coatings to ensure crank service life as well as reduced friction
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