b1driver

b1driver

Well Known Member
I have an I0-320 C1A that I'm converting the sump to so that it'll work with my 6A. I'm trying to finish up and have come to an unusual dilemma that a quick search here hasn't brought any threads on.. maybe I'm not searching for the correct terms. The mounting points on the engine are not exactly dynafocal and not conical, they have a cup to them on the backside that I was told by an A&P friend of mine that I need a certain type of bushing to make it fit right with the aircraft mount (dynafocal), but no specifics. Anyone have any info as to what this bushing is called so that I can source it, or better yet if you have a set that you'd like to part with? Thanks for any help you can give.

I do realize there is a type 1 and type 2 dynafocal mount but I'm not sure this is an angle issue, rather a design built into the engine because it came from a twin comanche.

Luis
 
The type 2 dynafocal mount is for Twin Comanche engines.
The Twin Comanche used prop extensions that altered the C/G point of the engine. The different angle of the mounts focused the dynamic center of the engine to that new point.
If your engine is from a Twin Comanche, you need the type 2 mount.
 
Thanks Mel, appreciate the quick reply. Im going to assume I have a type 1 mount, would purchasing the type 2 already fit the holes already drilled on the firewall. So these bushings that the guy was talking about wouldn't convert it? I apologize ahead of time for my ignorance on the subject.

The engine is in Salt Lake getting worked over before I install it and dont have direct access to it.. the mount was already installed onto the firewall when I purchased the pre-worked on kit. I'm in FL.

Luis
 
Disregard, just read from vans that dyna II engines are to be avoided and they are not supplying the mounts because of the scarcity. But I can get the case modified to fit dynafocal I mounts. Bummer.. THanks for the help Mel..

Luis
 
Just researched this last month, Dyna I & Conical style engine mounts are the only ones available now from Van's. Dyna II mounts no longer available. Divco Inc. in Tulsa can modify your crankcase from Dyna II to Dyna I configuration for $250.00. ECI does the same mod. I'm about to buy a batch of Twin Commanche IO-320-B1A engine parts and will be going this route to build my Rv9 motor. In the next month or so the parts I don't need will be for sale; cranks, cams, crankcase, acc cases, flywheels, gears ect, ect.



Don B.
RV9 Rebuild in Progress
 
Great Info Don, I thought it would be ALOT more to modify the case to Dyna I.... just gotta see about getting it down to Divco or ECI for modification now.

Luis
 
I don't know if this mod can be done with the engine assembled? Main guy there is very helpful and easy to deal with, call him.
 
Called and verified that indeed you have to part your case, but mine was close to that stage anyway so its not a big deal to go ahead and send them the case.. I can also vouch that its only 250 at Divco and thats where mine is going for the mod. Thanks a ton for the info fellas.

Luis
 
Before you go splitting your case and so on, you may consider touching base with Van's supplier of engine mounts.

When I had an issue with my -H2AD not fitting the standard mount (I knew I would, btw :p) , Vans put me onto them to source the correct tube to modify the mount. They probably cannot sell you a new mount if Vans is still stocking or "may" want to stock the Dyna-2 mounts in the future, but if there isn't any contractual limitation, you may be able to purchase a -6A Dynafocal-2 mount direct from them.

Super-12 is the company and the boss there, Steve, was more than helpful in getting me what I needed.
 
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