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The rise of FrankenEngine - An engine for the VP-21

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Joined
Nov 14, 2009
Messages
9,911
Location
Rocky Mountains
A bit of background:
A little more than a decade ago I decided I needed an engine for my Quickie project because the Onan was no longer available. I built a ½ VW with the intention of using that. Ultimately I decided that it wasn’t a good choice. This lead to thinking about building an engine from scratch and make it a for profit project. At the time I had access to the equipment and time to do just that. To keep it all manageable I decided to use as many off the shelf parts as I could to keep the custom work, and cost/time to a minimum.
Life changed for me and Pete introduced the O-100. The O-100 was so close to what I had designed (market niche, not design) I decided the project was no longer a commercially viable one. I no longer have the resources to build such and engine - but I haven't given up. I'm still working on an inverted 810 B+S, even if it ends up being just for my Quickie
With the O-100 in limbo and supply of the little v-twins looking a little precarious maybe it’s time to resurrect that old project? Thus, this new thread.

Objectives:
Gather ideas, in the spirit of the VP-21 and Motorcycle Of The Air threads, to design an engine suitable for this class of EABs. Project is to be open source so individuals can build from scratch, use cottage industry parts or buy complete FWF packages.

Controlling parameters:
Opposed 2 cylinder.
4 stroke direct drive
Maximum RPM = 3600 ………… less is better.
30+ Horse power. 40 would be better. This means 60 cubic inches (1.0L), or more, if we use 0.5 Hp/cu/ in. as a base line.
80 pounds maximum weight ready to bolt to the engine mount, minus prop and exhaust.
Should run on 85 octane E10 or low Sulfur Diesel (not both – pick one)
As many off the shelf (OTS) parts as possible. Minor modifications acceptable. This means those that can be done with hand tools or at ANY machine shop.
The OTS parts should be sourced from current production or past vehicles that have been produced in million+ quantities.
Simple. No dual OHC, VVT, variable compression, 12 valves per cylinder or antimatter containment fields.
Unless someone comes up with another option it will be presumed that this will mean a clean sheet engine case/block is needed along with either clean sheet heads or those built in the fashion of the ½ VW or ½ Corvair.
Past engines to use as templates:
Onan
1/2 VW
1/2 Corvair
Aeronca E-113
Conteniental A-40
O-100
Franklin 2 cylinders
 
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