BrendAn Posted May 30 Share Posted May 30 answer all of those questions in part 2, comming soon, but in short: They rebuilt the engine from ground and up. They start off by precision welding the crankshaft to make it a solid “one piece†crank to handle the increased power. Next they machine the crank case half and install piston oil squirters which job is to keep the pistons cool under high loads. They change the overload clutch settings in the gear box, install forged pistons with 8.3:1 compression ratio which had Teflon coated skirts and ceramic coated crowns. add their fully sequential fuel injection system with lambda sensor and the ECU has auto-tune features and individual injector trim to balance out any EGT spread. And they add the turbo and turbo exhaust and tune, break in and test the engine for 99 minutes on their test bench. They've stressed the cranks to well above 200hp, and broken a few, so they know exactly where the limits are... More than 250 such engines have been built since 2006 and none has failed. Some has more than 1200-1500 hours. So they have a perfectly good track record! Hope this helps? found this on a kitfox forum. don't expect to convince nev but they seem to be ok. Link to comment Share on other sites More sharing options...
facthunter Posted May 30 Share Posted May 30 Sorry for that but we brought up collectively the two engine types. I'm NOT a fast typer. IF you want to understand what I'm saying I think you will cope with it. Nev Link to comment Share on other sites More sharing options...
facthunter Posted May 30 Share Posted May 30 I have no idea why that came out in darker print. Nev Link to comment Share on other sites More sharing options...
facthunter Posted May 30 Share Posted May 30 The last line of your post is not called for Brendan and all the extra things beyond the crank is not relevant either. Any way you look at this crank it's a bit light on to be the basis of a hotted up engine.. IF I owned one I'd want to know how the stretching/ failing cylinder retaining studs are going to be overcome. When you only have 4 you don't want any failing.' When you weld the crank you make the rods non removeable forever. The big end eyes are not split or do they change that too.? I doubt there's room to do that and how do you weld that side of the crank web with a conrod there? Nev 1 Link to comment Share on other sites More sharing options...
BrendAn Posted May 30 Share Posted May 30 14 minutes ago, facthunter said: The last line of your post is not called for Brendan and all the extra things beyond the crank is not relevant either. Any way you look at this crank it's a bit light on to be the basis of a hotted up engine.. IF I owned one I'd want to know how the stretching/ failing cylinder retaining studs are going to be overcome. When you only have 4 you don't want any failing.' When you weld the crank you make the rods non removeable forever. The big end eyes are not split or do they change that too.? I doubt there's room to do that and how do you weld that side of the crank web with a conrod there? Nev Just pointing out that edge seem to be having success with what they are doing with Rotax engines. It doesn't really have anything to do with the thread . Link to comment Share on other sites More sharing options...
facthunter Posted May 30 Share Posted May 30 You could do that without directing it at ME personally. I try to deal in facts and not make it a personal thing unless in response to someone. We all want answers here. Engines are a major cost item in the scheme of things I've build and modified them all my life and done quite a bit of tertiary study as well. Really good ones are rare' Reciprocating motors will always be way behind Turbine ones. Nev Link to comment Share on other sites More sharing options...
BrendAn Posted May 30 Share Posted May 30 I said I don't expect to convince you. It's not an insult. You can't be upset over that. Link to comment Share on other sites More sharing options...
Red Posted May 30 Share Posted May 30 1 hour ago, facthunter said: The last line of your post is not called for Brendan and all the extra things beyond the crank is not relevant either. Any way you look at this crank it's a bit light on to be the basis of a hotted up engine.. IF I owned one I'd want to know how the stretching/ failing cylinder retaining studs are going to be overcome. When you only have 4 you don't want any failing.' When you weld the crank you make the rods non removeable forever. The big end eyes are not split or do they change that too.? I doubt there's room to do that and how do you weld that side of the crank web with a conrod there? Nev Stretching/failing studs? Are you confusing 2 different engines here? or just mixing 2 subjects in one reply again (Jab through bolts stretching/failing and Rotax cranks spinning) Link to comment Share on other sites More sharing options...
rhtrudder Posted May 30 Author Share Posted May 30 On 28/5/2024 at 6:36 PM, facthunter said: Watch how they stop when shut down. A good motor will bounce back off compression. Nev Don’t think my 914 has bounced back, maybe something to do with the reduction gearing 1 Link to comment Share on other sites More sharing options...
Area-51 Posted May 30 Share Posted May 30 2 hours ago, rhtrudder said: Don’t think my 914 has bounced back, maybe something to do with the reduction gearing Rotax don't bounce back as direct drive setups may. They just stop; and clunk. Even rolling them over by hand they no way feel as free spinning as a 360 or such. 1 1 Link to comment Share on other sites More sharing options...
Scotty 1 Posted May 30 Share Posted May 30 TOP PERFORMANCE AND NEW OPPORTUNITIES In addition, BRP-Rotax offers the 916iS/c as an alternative for IFR (Instrument Flight Rules) flights as well as for commercial flying, for example for flight schools and private pilots. The top performance of the 916iS/c allows for shorter take-off distances and steeper descent while maintaining maximum efficiency in cruise flight. For increased flexibility, the 916iS/c features multi-fuel technology (for MOGAS & AVGAS) which allows both classic engine fuel as well as aviation fuel. In this class up to 160 hp, the new propulsion system features fully electronic iS technology for increased performance, greater efficiency and simplified maintenance and servicing. This means that engine selection for maintenance and repairs can be carried out via the BUD system Aircraft (BRP Utility and Diagnostic Software for Rotax Aircraft Engines), in a similar way to the automotive industry. As a testament to BRP-Rotax’s confidence in this new propulsion system, the TBO (Time Between Overhaul) at product launch is 2,000 hours, which speaks to the value customers can derive from the engine. Link to comment Share on other sites More sharing options...
BurnieM Posted May 30 Share Posted May 30 (edited) Sorry Scotty1 but that is marketing speak; same as 915 but more power at more cost. I believe the 916 has a stronger crankshaft and crankcases but Rotax seem reluctant to confirm technical details. Edited May 30 by BurnieM 1 Link to comment Share on other sites More sharing options...
facthunter Posted May 30 Share Posted May 30 The Rotax has very little flywheel effect so has to idle faster and you are better to stop it as most do, From minimum idle speed. Nev Link to comment Share on other sites More sharing options...
facthunter Posted May 30 Share Posted May 30 I've tried hard to get details and what i get is some reinforcement of the crankcase and tapering the Parts where the crankshaft is pressed together so it's got more interference and torque testing to a higher figure. These shafts cannot be repaired. That is the factory statement. Nev Link to comment Share on other sites More sharing options...
BrendAn Posted May 31 Share Posted May 31 30 minutes ago, BurnieM said: Sorry Scotty1 but that is marketing speak; same as 915 but more power at more cost. I believe the 916 has a stronger crankshaft and crankcases but Rotax seem reluctant to confirm technical details. From what I have read the edge performance engine is popular because they get the horsepower without the complexity of the 916 . It's lighter too. It's interesting that they buy brand new crate engines from Rotax to modify on the understanding that all reference to Rotax is removed and replaced with edge labels. So edge absolve Rotax of any liability and provide their own warranty. The edge perf welded cranks have proven as reliable as the rest of the mods. They also made turbo and EFI kits for jabiru at one stage. I would love to know what output they achieved.. 1 Link to comment Share on other sites More sharing options...
facthunter Posted May 31 Share Posted May 31 Why would they want to do that with an engine that already has cooling problems and is not recommended to be used in Pusher situations . Nev Link to comment Share on other sites More sharing options...
BrendAn Posted May 31 Share Posted May 31 3 minutes ago, facthunter said: Why would they want to do that with an engine that already has cooling problems and is not recommended to be used in Pusher situations . Nev They didn't get much uptake in the jabiru kit so now they just supply parts for the people that own them. Doesn't mean I can't ask what the outputs were. Link to comment Share on other sites More sharing options...
skippydiesel Posted May 31 Share Posted May 31 (edited) Good-on-yah! BrendAn - welcome to the heretical questioning side😈 Edited May 31 by skippydiesel 1 1 Link to comment Share on other sites More sharing options...
facthunter Posted May 31 Share Posted May 31 Geez skip, what has that got to do with any facts? . Nev 1 Link to comment Share on other sites More sharing options...
Area-51 Posted May 31 Share Posted May 31 June 1st tomorrow... its now 18.21 EST... 🍩🧃🍫... ⏱📟⌛️📡🔭📪... 🤔.... should be an announcement any day now about a new engine that will change aviation for ever... 🤔🕰▶️ 1 Link to comment Share on other sites More sharing options...
facthunter Posted May 31 Share Posted May 31 We hear about such things frequently' . Trot it up. Nev Link to comment Share on other sites More sharing options...
Red Posted May 31 Share Posted May 31 5 hours ago, Area-51 said: June 1st tomorrow... its now 18.21 EST... 🍩🧃🍫... ⏱📟⌛️📡🔭📪... 🤔.... should be an announcement any day now about a new engine that will change aviation for ever... 🤔🕰▶️ A-51, at the risk of sounding like an idiot (yeah I know..again)😁 Is there something Incoming I missed? Link to comment Share on other sites More sharing options...
Area-51 Posted June 1 Share Posted June 1 13 hours ago, Red said: A-51, at the risk of sounding like an idiot (yeah I know..again)😁 Is there something Incoming I missed? No; just feels like its that time of year again when a "this will change everything" announcement happens, followed by six months of happy happy joy joy before "never heard of again" forum post emerges ☹️ Staying ahead of the bell end curve... 2 Link to comment Share on other sites More sharing options...
facthunter Posted June 1 Share Posted June 1 Yeah It rang a bell for ME too.. Nev Link to comment Share on other sites More sharing options...
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