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I have been looking at the Rotax 912ULS but do not want to mess with carbs and want more HP than the 100HP it offers. This EP915ECI is a core 912 engine with fuel injection and 1484cc big bore kit to push it to 120HP. It seems to offer a more modern version on a tried and tested core engine at a reasonable price. Looking for any experience with engine and customer service.
Here is another option if you don't want to use the big bore kit and only looking to replace the carbs.
I have a little Knowledge of the Edge 915. I think some of the biggest things that are more noticeable about this engine will be power. It's a beast.
The next thing is efficiency, I have had a few 912's apart, (new factory tested and old wore out) there are always 2 very rich cyc's and 2 cyc's that are in decent tune. This is a result of the old design of the carb system. With the Edge EFI system they trim each cylinder. So you get nice burn and max hp out of all cylinders.
Altitude compensating, accurately to keep max hp and efficiently.
And a bonus that happens with accurate fuel distribution is better fuel economy.
Second little bonus is Startability at all temps.
There are many internal modifications that are done inside the engine also that help with longevity also.
I know this is an old discussion, but this is my 2 bits.
We are still weighing our options with which engine to go with for our cruzer. What you state matches all of my research on their upgrades to the 912 engines and it looks very solid. It has been awhile since I did this research, but if my memory is correct there were a few things that concerned me about going that route. First it voids the warranty on the engine and there are only a few places that work on them. For me that was over 300 miles away. The other item was price. What was quoted me was more than the UL350is that I was also looking at. We are just starting the fuselage so we still have time to continue to research options. Appreciate the feedback.
Oh awesome, there is definitely a lot to consider when powering you plane. Sounds like you have some time to decide. I know prices of some engines have been going up like crazy. world supply problems. You have time to decide what is best for you. Have fun building. I decided to buy rather than build this time. Just so I can fly.
We were somewhat interested in the Edge 915 or their 912 with fuel injection but figured that this route wouldn't make much sense as their engines are not much cheaper than a Rotax 912iS or a 915 but come with a series of downsides: Factory warranty void, no redundancy (Rotax has redundant ECUs, critical sensors, fuel injectors, etc.), their engines haven't gone through the same testing, unknown long term service part supply, likely lower resale value, etc..
The SDS system is also getting good reviews, but also doesn't have any redundancy and a 912ULS + SDS is more expensive than a 912iS. I therefore think that the SDS only makes sense if somebody already has a 912ULS but wishes that he had the iS.
I understand Rotax has a new 6 cylinder prototype called the Type 936 - I assume it will not be available for some time and the price will probably be sky high.
I run an edge fuel injection on my 914 in my gyroplane. I plan to use one on my zenith when I build. The power is smoother and more reliable. You don't have to dink with carbs and it is just a better system overall.
My 914 is a big bore and puts out 140 HP for 5 minutes and 125 continuous. I use a variable pitch prop so it's a screamer.
IMO too much computer crap on the 915 series but if you need that much power it may be worth it.
Hi Heath, I have two questions about your high power Rotax:
- Do you run a welded crankshaft for this high power engine
- Which big bore kit do you use 1480 or 1622 cc, Zipper Edge or South Mississippi?
I considering a 1622cc on a CH 750 STOL. I fully agree with you about the carbs, however if they set up correctly the system is simple and light.
Yes a welded crank. It is similar to the zipper. I use a guy out of Nevada to build my engines and run about 140 to 145 hp.
Adding the edge system makes it incredibly simple and reliable
Is it generally accepted that crankshaft welding is recommended only on Edge big bore kits 140HP and above?
I am looking at Edge performance also. My primary concern is a firewall forward package. From reading other posts many people have gotten stuck at the firewall package, cowling, etc. I've asked the US dealer STOLcreek for some drawings to send to Skytek and see if their package is compatible, since they have packages for both the 912 and 914 and soon the 915 it seems likely they could put one together without too much effort.