Thar OMG. Planning an OMFG version.
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robtharalson robtharalson is online now
Old, Bold rider
 
Join Date: Jan 2007
Location: Aurora, Colorado
Posts: 2,475
Garage
Vehicle Name Thar OMG. Planning an OMFG version.
Year 2018
Make Thar Engineering
Model TE 001
Color TBD
Packages initially, a full on roadracer. Eventually, a naked version.
History Ever since seeing a Moto Guzzi V8 engine at the Cycle World display in 1968 it has been an obsession to make one of my own.
Bodywork
Thinking of using a fairing with electrorheological fluid as the prime mover in adaptive aerodynamics. It would actually change shape in response to external conditions.

Electronics
All sorts of computers. Also no incandescent light bulbs whatsoever. Screw Edison.

Engine Mods
2018 Thar Engineering TE 001 Engine Mods 2018 Thar Engineering TE 001 Engine Mods 2018 Thar Engineering TE 001 Engine Mods
It's a one litre 90 degree V8.
Bore: 70.5mm.
Stroke: 32mm.
Theoretical redline at 5000 Ft/Min mean piston speed: 23,800.
Since I'm designing the engine from scratch it can be referred to as one big mod.
*********** Images *************
The green rectangles are the size of a 100 dollar bill.

First picture:
The transmission. A cassette configuration. Both shafts are "hard stacked" similar to a typical automotive trans. No gears slide on their respective shafts, and all selectors are on the countershaft. While it is pressure fed motor oil, there is also a small trochoidal pump mounted on the countershaft feeding out of a collector trough below the shaft that will maintain lubrication when the motor is not running, allowing practically unlimited coasting without worrying about trans component damage.

Second picture:
The counterweighted crankshaft with rods. The green objects are tungsten slugs / inserts for counterweighting. The drive gears which engage gears on the jackshaft are in the middle to mitigate torsional vibration without using a damper. A quick 100 node FEA shows little in the way of issues, but for my peace of mind a few added bracing ribs from the rod journals to the main webs will be added. According to my calculations the weight without the rods pictured will be ~ 15 pounds. Not bad! Another feature is the crank is coated with a petrophobic material which prevents oil from adhering to treated surfaces, at least a goodly portion of it. Heat is drawn away by oil, therefore it will take a lot of experimentation to determine how much area will be treated and how much will remain untreated to maintain an acceptable crankshaft temperature.

Oil is fed from both ends of the crank. There are several reasons for this: it insures the rod bearings get an adequate amount of oil at all times, something that cannot be guaranteed with conventional feeds from the main journals without jacking up the oil pressure to astronomical levels. With "nose feed" the oil pressure does not have to overcome centripetal acceleration to get to the rods, cutting down the parasitic from driving the oil pump by as much as 60%.

Third image:
It has a dry sump system using a gear type pressure pump and two stages of roots type scavenge pumps. Both of these are used to reduce drag: the reason why the pump impellers are not the typical trochoidal type is there is a considerable parasitic. Using roots type impellers for scavenging and gear type pressure impellers reduces it by as much as 70%. Additionally, the dry sump system actually evacuates air (or whatever you want to call the gases in the motor) from the engine, reducing oil windage and actually reducing the air pressure to well below atmospheric mean, again reducing windage drag.

To help keep the front wheel somewhere near the ground when accelerating the crankshaft turns backward, using a jackshaft between the crank and clutch. I'm willing to live with the complication and extra drag, roughly 3%.

Another innovation: no camshafts. Valves are directly actuated using ultra fast solenoid valves feeding tiny double acting hydraulic cylinders. This allows not only variable lift and duration, but also can control the compression ratio in a similar fashion as an Atkinson cycle engine by leaving the exhaust valve open during the first part of the compression stroke, bleeding some of the air charge out. Obviously this would also vent out fuel in a port injection setup, so direct chamber injection will be used. Another advantage is that in low load conditions cylinders can be selectively deactivated in echelon to save fuel.

Initially, magnesium will be used for the major engine castings, but I am consulting with several aerospace composite manufacturers on the feasibility of carbon / boron reinforced cermet matrix for the majority of the engine cases. Also, I am working with a producer of refractories to make cylinder liners using a process similar to Nickasil coatings underlain with Rhenium refactory to maintain as high an efficiency as possible. A similar surface treatment will be applied to the piston crowns and above the first ring land, the combustion chamber, and the heads of all the valves. Gotta keep as much heat generated producing power instead of warming the atmosphere.

I anticipate a dry weight of the entire engine to be under 120 pounds / 55 Kg in magnesium, and about ten percent less in composite.

Exhaust system
The exhaust system will be a bit ... different as well. Ordinarily a pair of four into one systems would be the easiest, pretty efficient, and simple as the crankshaft is single plane unit enabling all four pipes from each bank of cylinders to feed a single collector. But "pretty efficient" doesn't cut it hereabouts (DUH!), so after 20 years of learning as much as possible about exhaust gas / wave dynamics, acoustic theory, and brain crushing theoretical calculations what we have come up with is a system I have dubbed Thar EERS. Exhaust Energy Recovery System. Essentially it is an exponential tapered megaphone for each cylinder, the taper of which begins at the exhaust port and continues to a reverse taper end including a mechanical damper assembly which also serves as part of the EERS system. That's all I can reveal for the moment. Needless to say packaging eight megaphones on a road racer platform is going to be a real bear, but given recent field tests it appears to be worth the effort

Suspension
Electrorheological shocks front and rear, coupled to load cells and controlled by a pretty small computer. With response times about ten times as fast as magnetic damping, and 1,000 times as fast as solenoid controlled damping, it is as close to a full active system as it can be.

Wheel and Tire
Yup, it will have two of both. CF wheels.
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