It's been suggested to me by someone more knowledgeable that the engine could be damaged by holding the engine at its RPM of maximum torque using prop loading, even under ambient pressure. Ron, I stand corrected!
Where the HP and Torque curves cross on your graph are arbitrary and depend on the scale of units used. The most efficient point with lowest specific fuel consumption is usually at max torque.
Dino
It's nice to see you sharing your development work where all can benefit. The setup looks promising.
Where the HP and Torque curves cross on your graph are arbitrary and depend on the scale of units used. The most efficient point with lowest specific fuel consumption is usually at max torque. 10,000 rpm looks like a good red line. If it is, plan on ground running at least a few hours at max rpm to verify all is well
If you are starting with a clean sheet you might consider this approach. Establish what is the max diameter of prop you can use. Efficiency of low speed gyros usually benefit from large props (stability issues excepted). Gear the prop to about 2500 rpm which in your case would mean a 4:1 ratio. If you go with a lower rpm you will make less noise. A higher rpm up to a limit of 65% mach tip speed will make more noise. Now the hard part. Select a prop AF (activity factor is similar to solidity ratio on a rotor and is adjusted by blade width or number of blades) that will absorb the power at 10,000 engine rpm. Finally set the blade pitch to give about 9500 engine rpm static.
Dino
Here's what is available today. These are dealers, so there are title and dealership fees, but sales tax won't apply since I am out of state.
(I like dealers rather than private sellers, since they are ready to crate and ship at a moment's notice, and the couple extra bucks in paperwork fees more than pays for itself off when it comes to shipping, the freight companies charge that much less since they are also dealing with commercial locations that have docks and lifts.
Carburetor models:
$3000, 5k mi + $500 title, S/H
$3200, 4k mi + $500 title, S/H
$3200, 7.6k mi + $500 title, S/H
FI Models:
$4000, 3.1k mi + $600 title, S/H
$4500, 6.6k mi + $600 title, S/H
$4500, 10.7k mi + $600 title, S/H
$4500, 5.1k mi + $600 title, S/H
$4500, 7.5k mi + $600 title, S/H
$4800, TBD mi + $500 title, S/H
Air Trikes PSRU, delivered from Canada, $1800
Pressure Clutch (not centrifugal) w/flexible coupling, $500
PSRU adapter, complete engine mounting kit, and double-thick core aluminum racing radiator w/cooling lines $2000
Complete SS Exhaust kit with muffler, EGT sensors (4), and vibration damping mounting system $1000
Engine prep (includes removal, bead blasting & polishing, and all custom work to adapt engine, ancillaries and electricals for gyrocopter installation, leak-down test data, & complete tune-up) $1000
Final S/H to your shop $199
TOTAL DELIVERED PRICE, ready to bolt-on to your mast and keel including engine from the lowest-price listed sled above:
$9999.00
Prices subject to change without notice, call for latest pricing.
Here's what is available today. These are dealers, so there are title and dealership fees, but sales tax won't apply since I am out of state.
(I like dealers rather than private sellers, since they are ready to crate and ship at a moment's notice, and the couple extra bucks in paperwork fees more than pays for itself off when it comes to shipping, the freight companies charge that much less since they are also dealing with commercial locations that have docks and lifts.
Carburetor models:
$3000, 5k mi + $500 title, S/H
$3200, 4k mi + $500 title, S/H
$3200, 7.6k mi + $500 title, S/H
FI Models:
$4000, 3.1k mi + $600 title, S/H
$4500, 6.6k mi + $600 title, S/H
$4500, 10.7k mi + $600 title, S/H
$4500, 5.1k mi + $600 title, S/H
$4500, 7.5k mi + $600 title, S/H
$4800, TBD mi + $500 title, S/H
.
This seems like a pretty good deal. SS Motorcycle headers will fit those engines and only run about $1000 new. Does the tach/instrument cluster come with the wiring harness, rectifier, fuses and EFI?
How do you verify mileage/hours on the engines if they are already out of the sleds?
Are they rebuilt? Cleaned up? Just out of curiosity, how did you come by so many engines?
I run a snowmobile salvage business that deals only with yamaha sleds.