MoTec

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Jaws

New Member
Joined
Dec 4, 2019
Messages
3
After reading, and talking to a local MoTec dealer, we are going to make the switch to this brand.

It has been stated on this forum that they are hands down the best available. And our dealer is an expert at programming. He has worked with a number of racers at Reno, and was scheduled to work with the P-51 Galloping Ghost before they had their accident.

Like the dealer told me, it does cost a bit more, but it is cheap insurance.
I'm the new guy I'm sure you heard this before. is anyone using dual over the counter ECU? how are they installed? re you using sharing sensors o
After reading, and talking to a local MoTec dealer, we are going to make the switch to this brand.

It has been stated on this forum that they are hands down the best available. And our dealer is an expert at programming. He has worked with a number of racers at Reno, and was scheduled to work with the P-51 Galloping Ghost before they had their accident.

Like the dealer told me, it does cost a bit more, but it is cheap insurance.
After reading, and talking to a local MoTec dealer, we are going to make the switch to this brand.

It has been stated on this forum that they are hands down the best available. And our dealer is an expert at programming. He has worked with a number of racers at Reno, and was scheduled to work with the P-51 Galloping Ghost before they had their accident.

Like the dealer told me, it does cost a bit more, but it is cheap insurance.
After reading, and talking to a local MoTec dealer, we are going to make the switch to this brand.

It has been stated on this forum that they are hands down the best available. And our dealer is an expert at programming. He has worked with a number of racers at Reno, and was scheduled to work with the P-51 Galloping Ghost before they had their accident.

Like the dealer told me, it does cost a bit more, but it is cheap insurance.
 

Jaws

New Member
Joined
Dec 4, 2019
Messages
3
I'm a new guy here. I'm interested in a dual ECU on P-port 13b. is anyone running one? Are using dual sensors or sharing sensors, firing one ignitor per ECU at the same time and one injector per rotor with sperate ECU? Tracy's ECU's are not available. Just asking questions?
 

rv7charlie

Well-Known Member
Joined
Nov 17, 2014
Messages
544
Location
Jackson
I'm a new guy here. I'm interested in a dual ECU on P-port 13b. is anyone running one? Are using dual sensors or sharing sensors, firing one ignitor per ECU at the same time and one injector per rotor with sperate ECU? Tracy's ECU's are not available. Just asking questions?
If you're serious about flying a rotary, I'd strongly suggest subscribing to the Flyrotary list; that's where you'll find most of the rotary guys who are actually flying (at least the ones that bother with being present on the interwebs :) ).

Controllers: Tracy's controllers for a/c have dual redundant controllers, with relay switching for the injectors and ignition coils. The only common sensor is the crank angle sensor, which is somewhat difficult to duplicate on a rotary without some fairly serious machine work. No convenient way to add a 2nd CAS to Tracy's controller, but it could be done. Would require both hardware and software mods to the controller.

Individual, isolated control of rotors is a very bad idea, for a couple of reasons. The 13B/Renesis is a 2-per-rev engine, like a 4 stroke 4 cylinder, but unlike a piston engine, there's no torque reversal between power strokes due to the long duration (relative to crank rotation) of the power stroke. But if you lose one rotor, you get torque reversal and the engine dynamic balance goes really wonky (redneck layman's terms) and can get destructive quick. Anecdotal evidence: one builder/flier flew an ERacer (canard pusher) for years and hundreds of hours using a Mazda 4 speed transmission in 2nd gear, and it was very successful. But one day he fired it up, and for some reason only one rotor was firing (I've forgotten what he used for fuel/spark; might have been the stock distributor & a carb). It destroyed the transmission while running at idle power. The other reason to avoid the idea is that even without the destruction possibilities, you've lost over 1/2 the power of the engine; not just a bit over 1/4 of the power you'd lose in a 4 cyl engine. In many airframes, you may not have enough left to sustain flight even if everything stays in one piece.

Dual redundant controllers could be done using Mega/Micro-Squirt hardware; it would just require a relay board to do the injector/coil switching, and a bit of monkey-motion to add in-flight mixture control.

Charlie
Renesis FWF in progress on an RV-7
 

Neil Unger

Member
Joined
Oct 27, 2019
Messages
13
Jaws,
Motec is a top of line ECU but very complicated and heavy on the bank account. If still looking try fueltech or SDS who does now make one for the rotary. Reduction drives Look at Rotarpower. Many choices, your decision.
 

rv7charlie

Well-Known Member
Joined
Nov 17, 2014
Messages
544
Location
Jackson
I've heard rumors that SDS was in discussions with someone to make a rotary controller, but the SDS website still shows 'fuel only' for rotaries.

Another potential option for dyi is
https://speeduino.com/wiki/index.php/Speeduino

A well respected former controller mfgr is looking at it with interest as a next gen rotary controller.

Charlie
 
Last edited:

AIRCAB

Well-Known Member
Joined
Feb 6, 2015
Messages
55
Location
Vancouver Island
Rv7charlie, I was under the impression, from reading Ross Farnham posts from the last 10 years , we was anti rotary.

Steve
 

rv7charlie

Well-Known Member
Joined
Nov 17, 2014
Messages
544
Location
Jackson
Rv7charlie, I was under the impression, from reading Ross Farnham posts from the last 10 years , we was anti rotary.

Steve
Historically, that's been my impression as well. But he reads this forum, so if he now has a different opinion, he'll likely speak up.

Charlie
 
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