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  • #16
    Re: Sport Glass Gold Kitplanes Article

    Originally posted by IcePaq View Post
    Since air racing does see a few engine related mayday pull-ups, I'm surprised nobody tried the porsche turbo flat six.

    Once you go racing, reliability as compared to stock suffers greatly.

    They are twin plug head engines and we rarely rebuilt ours in a porsche 935 that accumulated 60,000 racing miles about half of which were at 750hp.

    I understand the "it's a car engine" guys will chime in but what's limiting HP on the current lycoming and continental engines is that the designs were made to keep everything "low stress" in the interest of safety.

    This is done by keeping piston and valve speeds down, managing cylinder pressure, and managing temperature such that aviation engines are in a pretty low stress environment.

    It's cool that many can use the current lycoming/continental designs and race them without raising the stress much but we aren't seeing the stellar reliability of the stock offering once you change the basic engine/gearbox/prop. package even the slightest bit.

    An engine program to raise the revs would surely cost more than taking a porsche turbo 3.3 liter......or whatever size you want from 2.0 to over 4.0 netting you anywhere from 450hp all the way to 750hp that lives long enough for a 24 hour endurance race (in a car).

    The engine shape is similar to the engines it would replace.

    With two separate haltec/megasquirt/(insert any other name brand) engine management systems, you can achieve some measure of reliability and have tuning for each cylinder's mixture and timing.

    If you're already impacting reliability, why not have twice the horsepower available?
    750hp @ 8000 rpm. How much to develop a gearbox? How long to make it reliable?

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    • #17
      Re: Sport Glass Gold Kitplanes Article

      Originally posted by IcePaq View Post
      Since air racing does see a few engine related mayday pull-ups, I'm surprised nobody tried the porsche turbo flat six.

      Once you go racing, reliability as compared to stock suffers greatly.

      They are twin plug head engines and we rarely rebuilt ours in a porsche 935 that accumulated 60,000 racing miles about half of which were at 750hp.

      I understand the "it's a car engine" guys will chime in but what's limiting HP on the current lycoming and continental engines is that the designs were made to keep everything "low stress" in the interest of safety.

      This is done by keeping piston and valve speeds down, managing cylinder pressure, and managing temperature such that aviation engines are in a pretty low stress environment.

      It's cool that many can use the current lycoming/continental designs and race them without raising the stress much but we aren't seeing the stellar reliability of the stock offering once you change the basic engine/gearbox/prop. package even the slightest bit.

      An engine program to raise the revs would surely cost more than taking a porsche turbo 3.3 liter......or whatever size you want from 2.0 to over 4.0 netting you anywhere from 450hp all the way to 750hp that lives long enough for a 24 hour endurance race (in a car).

      The engine shape is similar to the engines it would replace.

      With two separate haltec/megasquirt/(insert any other name brand) engine management systems, you can achieve some measure of reliability and have tuning for each cylinder's mixture and timing.

      If you're already impacting reliability, why not have twice the horsepower available?
      Going to need a gear box engineered and built. Most likely need a whole new crank design due to harmonics too Then you still have an auto engine in an airplane which has been proven over and over and over again to be an ill-conceived idea. Plus Mooney already did it. Made mid 200s for HP with any sort of reliability. I know a couple of guys that owned them, and both said they were pretty terrible. https://en.wikipedia.org/wiki/Porsche_PFM_3200
      Last edited by Race5; 10-13-2016, 06:16 PM.

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      • #18
        Re: Sport Glass Gold Kitplanes Article

        Porsche gave up after millions, and millions. Why would anybody even try?

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        • #19
          Re: Sport Glass Gold Kitplanes Article

          Here's a great article on the engine development for the GP-5 "Sweet Dreams". I think this is about the most successful application of an automotive engine for use in air racing and there we A LOT of mods needed to get to this level.

          Sky Critter

          Comment


          • #20
            Re: Sport Glass Gold Kitplanes Article

            Originally posted by IcePaq View Post
            An engine program to raise the revs would surely cost more than taking a porsche turbo 3.3 liter......or whatever size you want from 2.0 to over 4.0 netting you anywhere from 450hp all the way to 750hp that lives long enough for a 24 hour endurance race (in a car).

            The engine shape is similar to the engines it would replace.

            With two separate haltec/megasquirt/(insert any other name brand) engine management systems, you can achieve some measure of reliability and have tuning for each cylinder's mixture and timing.

            If you're already impacting reliability, why not have twice the horsepower available?
            It could be a good idea, but I believe the current front runners in the sport class are already making around 750 hp. Maybe if the Porsche had less cooling drag than aviation engine it would make more sense.
            Random Air Blog

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            • #21
              Re: Sport Glass Gold Kitplanes Article

              Originally posted by CJAM427 View Post
              I legitimately had a dream about this last night, I was trying to figure how to help Team One Moment (Race 30) keep their engine cool. I don't think I came up with a solution haha. What's different with the Lycoming that makes it seem more reliable than the Continental?

              I am very excited to see what Tom's Lycoming powered Legacy can do!
              Well, my opinion, and that is all it is at this point, is the Lycoming just has more meat in it. It is about 80 lbs heavier than the Continental. Although that figure varies a lot depending on what is on the engine..

              Now, that being said, in a stock to stock normally aspirated comparison, the Continental makes more power, hands down. I attribute that to the much more efficient intake system flowing from the top down. The Lycoming system is less ideal, and I suspect part of the lower horsepower output. Another stock to stock comparison that is rather important to me is cylinder longevity. How many have seen a Continental with low compression before TBO? (Time Before Overhaul) It seems like every Cirrus I've seen has had a top end at less than 800 hours. Most Lycomings (run properly) will literally take a cylinder to TBO.

              One byproduct that is going to be a concern for me is the 580 cylinder vs the 540 cylinder. The 580 is a one time use cylinder, no boring.. There isn't enough wall thickness to allow for an overhaul. The 540 can be bored, and is actually a stronger cylinder because of the extra material. I ended up with the "There's no replacement for displacement" theory and went with the 580 in the hopes that I can make it last long enough. It has worked for #39 for a while..

              When you go forced induction, the intake inefficiency of the Lycoming can be overcome pretty easily. Although to really maximize the intake system it takes some pretty drastic changes from 'stock', which I'm planning to do. The more I learn about Turbo's, the more I like it. It is going to be difficult to fly cross country and not throttle it up. Although when I get the fuel bill, I'll probably remember to pull it back to 250 kts.

              Donald got it correct on who has run what, as I see it.
              Unleashed Air Racing

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              • #22
                Re: Sport Glass Gold Kitplanes Article

                I seriously doubt any are making north of 550 hp.

                Gearboxes don't need to be created by a U.N. resolution and 10 billion dollar budget to work for air racing while every other form of motorsport has no trouble making them.

                Some tractors make 20,000 hp and thier gearboxes handle it.

                Unlimited hydroplanes ran huge HP with piston engines where the shock loading was intense enough to snap quill shafts on Griffons because the engine revs. changed so rapidly.............which I haven't yet seen in an airplane unless it was a 60 year old part with fatigue.

                Thier gearboxes didn't grenade making the cost too prohibitive to race.

                We have a record holding mile racer that's daily driven on the street that puts down 2700hp at 10,000 + rpm. through our custom made billet transmission based on the stock unit's basic design.

                It's shifted clutchless and the shock loads are insane yet it doesn't break and it wasn't a bank breaker.

                The porsche opposed six makes 750hp within a tight rule set and does so for races that run 24 hours.

                It's easily a 1000hp engine outside of IMSA GTO/GTP rules and will likely deliver that horsepower for an entire reno race week.

                The mile racers are starting to show up with 1500hp porsche opposed sixes.

                If you show up in the class being discussed with a 1000hp engine, you will rarely have to run the full power level for the entire race...........until someone else shows up with the same power level.

                The Nascar V8s ran 900hp until the end of 2014 for great lengths of time but they are awful wide.

                An inline six package can be made very narrow and many are known to be capable of 2000hp (nissan RB and toyota 2jz).

                The biggest issue to deal with extended running of high boost levels in turbocharged planes is how to manage the heat of the exhaust piping between the head and the turbos.

                Air racers seem to be willing to spend huge on some equipment while not even considering spending a dollar on other parts that will give them an edge.

                That's why we still see magnetos and carburetors.

                It's really the only motorsport what I see this and I find it strange.
                Last edited by IcePaq; 10-13-2016, 11:29 PM.

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                • #23
                  Re: Sport Glass Gold Kitplanes Article

                  Originally posted by Dudewanarace View Post
                  Well, my opinion, and that is all it is at this point, is the Lycoming just has more meat in it. It is about 80 lbs heavier than the Continental. Although that figure varies a lot depending on what is on the engine..

                  Now, that being said, in a stock to stock normally aspirated comparison, the Continental makes more power, hands down. I attribute that to the much more efficient intake system flowing from the top down. The Lycoming system is less ideal, and I suspect part of the lower horsepower output. Another stock to stock comparison that is rather important to me is cylinder longevity. How many have seen a Continental with low compression before TBO? (Time Before Overhaul) It seems like every Cirrus I've seen has had a top end at less than 800 hours. Most Lycomings (run properly) will literally take a cylinder to TBO.

                  One byproduct that is going to be a concern for me is the 580 cylinder vs the 540 cylinder. The 580 is a one time use cylinder, no boring.. There isn't enough wall thickness to allow for an overhaul. The 540 can be bored, and is actually a stronger cylinder because of the extra material. I ended up with the "There's no replacement for displacement" theory and went with the 580 in the hopes that I can make it last long enough. It has worked for #39 for a while..

                  When you go forced induction, the intake inefficiency of the Lycoming can be overcome pretty easily. Although to really maximize the intake system it takes some pretty drastic changes from 'stock', which I'm planning to do. The more I learn about Turbo's, the more I like it. It is going to be difficult to fly cross country and not throttle it up. Although when I get the fuel bill, I'll probably remember to pull it back to 250 kts.

                  Donald got it correct on who has run what, as I see it.
                  Any idea how much of that 80 lbs comes from individual parts? Is it mostly in the cases, or do the Lycomings have "beefier" rods and crank? Looking back at most of the engine failures in the fastest Sport Gold guys, most seem to be centered around either melting pistons, or sticking rods through the cases (which is caused by failed pistons a lot of times). I think 99% of the issues are more centered around ADI systems, turbo setup and the fuel injection. My guess is that is where the Glasair really shines. His systems management is more on point than anyone else's right now. I had a long talk with one of the OG Rare Bear guys who told me what all it took to make just the ADI system work consistently under the varying G loads, etc. It's a far more complex thing than most people imagine it to be.

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                  • #24
                    Re: Sport Glass Gold Kitplanes Article

                    Really getting some good discussion!

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                    • #25
                      Re: Sport Glass Gold Kitplanes Article

                      Originally posted by Race5 View Post
                      Any idea how much of that 80 lbs comes from individual parts? Is it mostly in the cases, or do the Lycomings have "beefier" rods and crank? Looking back at most of the engine failures in the fastest Sport Gold guys, most seem to be centered around either melting pistons, or sticking rods through the cases (which is caused by failed pistons a lot of times). I think 99% of the issues are more centered around ADI systems, turbo setup and the fuel injection. My guess is that is where the Glasair really shines. His systems management is more on point than anyone else's right now. I had a long talk with one of the OG Rare Bear guys who told me what all it took to make just the ADI system work consistently under the varying G loads, etc. It's a far more complex thing than most people imagine it to be.
                      I can't say for sure where the weight is compared to the Continental. But, show me any competition aerobatic airplane with an IO-550.. Now think how many are IO-540's..

                      I suspect part of the weight is due to the casting of the engine case, primarily for the dynafocal engine mounts. It takes some extra material to hang the engine from the aft end, where as the Continental is a bed mount engine. It sits in a cradle basically. That makes it lighter, but you pay for it in engine mount complexity / weight.

                      Now, all 540's are not created equal. The particular core engine I used was actually a TIO-540-AE2A. It is known for being one of the strongest Lycoming 540's in regards to pretty much everything. But, I wanted the roller cam because of an optional cam profile offered by LyCon. So, to get rollers, I had to use different cases, actually an AEIO-540 something.. I forget the last part of the designation. Basically it has the big bearings of the AE2A, but also capable of roller cam. Then the case was modified to take the 580 cylinders. (bored out) So the end result is a combo that isn't 'off the shelf' really.

                      In regards to pistons, I think you are correct in that anybody can melt any piston if it is run poorly. That is where the ADI really gets everything a bit more critical. The fine line between working and melting is tricky. Initially I'm planning on running as much as I can without ADI, and only develop that system after everything else is worked out and reliable. No need to go from zero to hero, that usually doesn't work out.
                      Unleashed Air Racing

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                      • #26
                        Re: Sport Glass Gold Kitplanes Article

                        Originally posted by IcePaq View Post
                        I seriously doubt any are making north of 550 hp.
                        ~edited down~
                        The biggest issue to deal with extended running of high boost levels in turbocharged planes is how to manage the heat of the exhaust piping between the head and the turbos.

                        Air racers seem to be willing to spend huge on some equipment while not even considering spending a dollar on other parts that will give them an edge.

                        That's why we still see magnetos and carburetors.

                        It's really the only motorsport what I see this and I find it strange.
                        Generally speaking, to cover the gear box / big horsepower development side of the conversation, it is just a matter of money at this point. Find someone who wants to put millions in this (that is what it would take) and it will happen. Or they can just go buy Strega and get the instant fame. I've hung V8's on airplanes so I know a little about what you are talking about. The car side gives you tremendous power for the money, not to mention low entry costs. Getting that power through a propeller is a totally different story. Literally the entire firewall forward package can be made or broken by the gearbox. What we ended up on the P85 seems to be working well, and it is extremely simple and low cost. But, 450 hp is the most you should really put through a standard fixed pitch prop flange. So if you're going north of that, totally new drive is needed. Geared Drives used to offer one with big power, constant speed options. I've just never seen one actually work. The Thunder Mustang drive is the only one I know of with the most hours on it, and they haven't been so reliable either.. I'd consider those pretty big budget too.

                        Props that can take 1000 hp are a totally different subject. Because we're not racing WWII fighters, ground clearance is an issue. That makes small props with big horsepower a rather difficult science.

                        Then you have the airframe.. What is available that can take 1000 hp, lets say 500 mph? Not much. The Legend, before it was a Turbine Legend could. I think we're over what a Glasair III should do, same with a Legacy. When you start developing a new airplane to take this power and speed, there goes a few more million just to design and tool up for 1 airplane.

                        Now, I'm not sure I follow the comment about spending money in odd places. I mean, to each their own, sure I get that. But, at the top of the Gold in Sport Class, there is some pretty big money spent on things that are definitely needed. I mean, I just dumped an additional $2K into my damn helmet which will do nothing for me speed wise, but maybe I can breathe in a fire. Stuff like that. At the same time, $300k to $500k in a true Sport Gold airplane is totally normal, some have a lot more.

                        I will not have a carb, or mags either. Now, not to defend mags, but if you know the power setting you are going to run, mags work. Top fuel drag cars run mags. You just can't be flexible with the power setting. I want an airplane that not only hauls ass racing, but hauls ass lean of peak across the country too, so I'm going electronic ignition. Not to mention if you go ADI, the instant flexibility of being electronic is worth a lot to me. But, fixed rpm, fixed power (manifold pressure), spark is spark, and mags don't need a battery.
                        Unleashed Air Racing

                        Comment


                        • #27
                          Re: Sport Glass Gold Kitplanes Article

                          Originally posted by Dudewanarace View Post
                          Generally speaking, to cover the gear box / big horsepower development side of the conversation, it is just a matter of money at this point. Find someone who wants to put millions in this (that is what it would take) and it will happen. Or they can just go buy Strega and get the instant fame. I've hung V8's on airplanes so I know a little about what you are talking about. The car side gives you tremendous power for the money, not to mention low entry costs. Getting that power through a propeller is a totally different story. Literally the entire firewall forward package can be made or broken by the gearbox. What we ended up on the P85 seems to be working well, and it is extremely simple and low cost. But, 450 hp is the most you should really put through a standard fixed pitch prop flange. So if you're going north of that, totally new drive is needed. Geared Drives used to offer one with big power, constant speed options. I've just never seen one actually work. The Thunder Mustang drive is the only one I know of with the most hours on it, and they haven't been so reliable either.. I'd consider those pretty big budget too.

                          Props that can take 1000 hp are a totally different subject. Because we're not racing WWII fighters, ground clearance is an issue. That makes small props with big horsepower a rather difficult science.

                          Then you have the airframe.. What is available that can take 1000 hp, lets say 500 mph? Not much. The Legend, before it was a Turbine Legend could. I think we're over what a Glasair III should do, same with a Legacy. When you start developing a new airplane to take this power and speed, there goes a few more million just to design and tool up for 1 airplane.

                          Now, I'm not sure I follow the comment about spending money in odd places. I mean, to each their own, sure I get that. But, at the top of the Gold in Sport Class, there is some pretty big money spent on things that are definitely needed. I mean, I just dumped an additional $2K into my damn helmet which will do nothing for me speed wise, but maybe I can breathe in a fire. Stuff like that. At the same time, $300k to $500k in a true Sport Gold airplane is totally normal, some have a lot more.

                          I will not have a carb, or mags either. Now, not to defend mags, but if you know the power setting you are going to run, mags work. Top fuel drag cars run mags. You just can't be flexible with the power setting. I want an airplane that not only hauls ass racing, but hauls ass lean of peak across the country too, so I'm going electronic ignition. Not to mention if you go ADI, the instant flexibility of being electronic is worth a lot to me. But, fixed rpm, fixed power (manifold pressure), spark is spark, and mags don't need a battery.
                          I think that whole lean of peak thing (taken to an extreme) is one of the main reasons we see so many Cirrus not making it to TBO. They seem to all run them WAY LOP all the time.

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                          • #28
                            Re: Sport Glass Gold Kitplanes Article

                            Originally posted by IcePaq View Post
                            I seriously doubt any are making north of 550 hp.
                            This data tag from the engine in Relentless could be a joke, but for what its worth... https://www.facebook.com/relentless4...type=3&theater

                            Random Air Blog

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                            • #29
                              Re: Sport Glass Gold Kitplanes Article

                              The props and hubs exist in the 1000s of turboprop applications of many different sizes, blade area, and length.

                              Because of this, the gearboxes also already exist.........you just have to change ratios or eliminate a stage since many are around 15:1 reduction.

                              This is surely less expensive than fabricating one from scratch.

                              For our car with a custom gearset, we simply gave the fabricators the stock unit, desired ratios, and the replacement gears showed up in the mail.

                              These gears handle clutchless shifts while being driven with up to 2700hp.......and have been since 2009.

                              We also replaced some of the cast housings with parts machined from billet.
                              Last edited by IcePaq; 10-15-2016, 06:18 PM.

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                              • #30
                                Re: Sport Glass Gold Kitplanes Article

                                Originally posted by IcePaq View Post
                                The props and hubs exist in the 1000s of turboprop applications of many different sizes, blade area, and length.

                                Because of this, the gearboxes also already exist.........you just have to change ratios or eliminate a stage since many are around 15:1 reduction.

                                This is surely less expensive than fabricating one from scratch.
                                Turbine power output is totally different than piston engine power output. The harmonics from a turbine are almost nothing compared to a 4 stroke piston engine. Constant load vs power pulses. Remember a prop is a giant tuning fork.

                                I ran into that with Unleashed. Because I have 10:1 compression and rather high horsepower output for a 4 cylinder (2 power pulses per revolution) there isn't a prop that exists to make me go faster. Hartzell won't even sell a blade that is thought to be better aerodynamically because of the vibration.

                                All of the above is true for gearboxes as well.

                                I'm glad your car applications work, but I'd be more impressed if you developed it for airplane use. You'd have a product to sell for sure.

                                Worth the read..
                                Last edited by Dudewanarace; 10-15-2016, 07:50 PM.
                                Unleashed Air Racing

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