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RV-7A with GM's LS1 V8

I saw the Mazda.... I haven't yet seen a substantiated equal weight Subaru.

Seriously? *sigh*

How much more substantiated would you like my data to be? I'm not going to go do the work, but I am curious just exactly what it would take.

A lot of builders use bathroom scales to weigh their Lycoming powered aircraft. Do we accept that their data is accurate?

-Dj
 
Most RV6As that I've seen on VAF with listed empty weights over the years are in the 1050-1100 pound range similarly equipped. I know of very few Lyc 6As weighing under 1000 pounds unless they have 320s and a wood prop.
 
Don't let the weight Federales get you down!

Hey Alt engine builders,

I experienced similar disbelief when I posted that I had built a 975 lb RV8A. That's with the pants and fairings, a 2 axis AP and 'some' paint. I eventually posted a pic of it on the scales at the local A&P before there was silence on the line. Not to say that everyone thought I was full of it. Some of the more math oriented did their own calcs based on what I posted, and completely got it.

So keep on building! Personally, I went with the Lyc on the RV because I'm lazy, and wanted to get in the air quickly. I would love to have that P85 tho...

Lance
 
I'd agree with Ross. Out of ~10,000 Lyc powered RV-Xs built, I'd bet that you could count every one that's within 5 lbs of the factory prototype, and not run out of personal digits. Might still be a safe bet at 20 lbs.

But back to the V-8. Details! Not that interested in a/c weight, but I'd love to see weights of engine, redrive, radiator, etc. Radiator face area & volume. Engine controller. Etc, etc.
 
There now seems to be a hang-up in the context that if the weight difference isn't actually 100 lbs, it doesn't matter......

Yes, actual empty weights of completed RV's vary. If you account for the variability of the average empty weight and say that the difference compared to a sub installation is only :rolleyes: 65 pounds, that is still significant.

There is always comments about naysayers ignoring the facts....

The fact is there are lots of people now flying RV's with Lycomings after swapping out a failed or unsupported sub. engine install. They know exactly what the weight difference is. The info is out there for anyone that actually wants to find it.
 
The fact is there are lots of people now flying RV's with Lycomings after swapping out a failed or unsupported sub. engine install. They know exactly what the weight difference is. The info is out there for anyone that actually wants to find it.

If you ask them, they almost always made other changes to the aircraft when making the engine swap, so they don't know *exactly* what the difference is, that is another reason why I actually weighed the components so I would know the difference, not simply guess at it like many do.

Scott, I'm really not sure what your argument is. We already know that some Lyc installations can be lighter than a Subaru installation. We also know that some Subaru installations can weigh the same as some Lyc installations. What is your point exactly?

-Dj
 
As we've seen countless times, some folks will take pretty well any opportunity to diss alternative engines, for any reason. Simple fact is that there are pros and cons to every engine. If you don't like the idea, don't use them.

Instead of congratulating people for the extra work and execution of the engine installation, they feel it's necessary to discuss all the possible pitfalls. Most anyone who did their own alternative engine install has already heard them all.

I posted this several months back: http://www.vansairforce.com/community/showthread.php?t=147804

Bjorn has no plans to remove his Subaru. I believe he's planning to install a more powerful one actually.

Back to the LS1 RV7A, There was an extensive article in Custom Planes a number of years back. I can't locate my issue any more unfortunately. I was certainly intrigued when I saw it.
 
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DJ good luck with your build.
Would be interesting to see the W&B of the V-8 RV.

Here is W&B of two very similar airframes to compare. Both were weighted on the same certified scales.

RV-7 IO360, Hartz C/S, Tip-up.
Empty: 1136 CG empty: 79.06

RV-7 EJ257 STI(modified Egg engine), Turbo, Intercooler, 3rd radiator, MT prop, Tip-up
Empty: 1237 CG empty: 78.39

Comparing to DJ's 6 cyl, this one is a 4 cyl (bit lighter than 6), with Turbo (30lbs extra), Rad & Intercooler (15lbs), but similar installation details and still comparably heavier than a Lycoming installation. The positive to this Turbo Subie installation is the big HP boost more than compensates for the weight increase. (acknowledging the many other factors the extra weight affects)
 
Here is W&B of two very similar airframes to compare. Both were weighted on the same certified scales.

Hi Ralph,
Thanks for sharing this data.

The issue, as I see it, is that these are two different aircraft (even if the same model) and probably built by two different people. We have absolutely no way to know what differences there are between these two aircraft from the firewall aft, and what weight difference that makes, including what choices the respective builder may have made during construction, primer, paint, equipment, etc. That leaves us to "guess" about the FWF weights, and I dislike guessing.

The only way we can use empty weight as a comparison is if the same aircraft was used to install both FWF packages, and nothing aft of the firewall was changed between the FWF swaps.

The proper way to compare the weight of two FWF packages is to weigh everything forward of the firewall, and compare those numbers directly. Anything else still leaves a lot of guesswork which leads us to having discussions like this thread. :)

-Dj
 
It is sad that a lot of information regarding successful engine conversions is supposed to be taken at face value, but when anything is detected as even slightly negative, a way is found to discount it. Anti alternative engine people are always criticized for being closed minded, but it appears to go both ways.

If weight differences in many instances of engine swaps are mentioned, it is discounted because engine swaps "always result in other changes happening at the same time" that makes the information useless.
How do you know that?
I know of numerous instances where it was not the case. Changes to airplanes (other than removing some alternative engines) rarely make them lighter, but even if that were the case, that would mean that the weight reduction change by switching to a Lyc would have been even more than 105 lbs, because the new changes likely added some weight.

Or in other cases were very similarly equipped airplanes have weight differences of 100 lbs or more, it is discounted because evidence is not being provided the proves the airframes are otherwise exactly the same.

If your goal is to know that the weight difference is 85 lbs vs 100 lbs, this is important. But a difference of 85 lbs is still not trivial and will have to be dealt with, which makes this info still useful to people working through the decision on what powerplant to use.

I am involved in experiments with RV's on just about a daily basis so I am not ignorant on the importance of the fine details. But I also know that when we are talking about big differences that influence performance, that info can be very useful as well, even if we don't know an exact # down to the pound or Kt.

Regardless of what may be thought, I am not anti alternative engines. These forums are full of older posts I have made regarding the subject, so I wont bother repeating any of it (and causing this thread to drift off the cliff any further after this).


What I am a big proponent of is full disclosure of the real world experience that experimenters have... all of the good and the bad.
That comes from years (decades actually) of dealing with RV builders via tech support and seeing the aftermath that results from them not going deep enough with there research.

If a subi engine installation can be done that results in an airplane with a power to weight ratio that is equal to that of a Lycoming, then the far right side of the experimental movement has failed a lot of people because there is tons of evidence to show that if it is being done successfully, only a small percentage that try are able to find the holy grail they seek.

If it is something easily within reach there must be a serious break down within the experimental culture.....
 
I'm afraid that the thread drift and off-topic debate (the topic being interest in this particular airplane, not alternative engine pros and cons) may have scared Mike (LS1RV7A) away, before he could get back to the keyboard to make his post #2 on VAF. That would be a shame.

In any case, Mike, thanks for stepping forward and letting us know the airplane is still flying. If you want to share more info, there's a lot of friendly interest. If a fella was to show up in LGB in a Super Six (a bit of an off-piste engine as well), maybe he could get a peek, maybe?

The racer in me just makes me curious about all the possibilities.

Hope to hear more! :)

Cheers,
Bob
 
It is sad that a lot of information regarding successful engine conversions is supposed to be taken at face value, but when anything is detected as even slightly negative, a way is found to discount it. Anti alternative engine people are always criticized for being closed minded, but it appears to go both ways.

If weight differences in many instances of engine swaps are mentioned, it is discounted because engine swaps "always result in other changes happening at the same time" that makes the information useless.
How do you know that?
I know of numerous instances where it was not the case. Changes to airplanes (other than removing some alternative engines) rarely make them lighter, but even if that were the case, that would mean that the weight reduction change by switching to a Lyc would have been even more than 105 lbs, because the new changes likely added some weight.

Or in other cases were very similarly equipped airplanes have weight differences of 100 lbs or more, it is discounted because evidence is not being provided the proves the airframes are otherwise exactly the same.

If your goal is to know that the weight difference is 85 lbs vs 100 lbs, this is important. But a difference of 85 lbs is still not trivial and will have to be dealt with, which makes this info still useful to people working through the decision on what powerplant to use.

I am involved in experiments with RV's on just about a daily basis so I am not ignorant on the importance of the fine details. But I also know that when we are talking about big differences that influence performance, that info can be very useful as well, even if we don't know an exact # down to the pound or Kt.

Regardless of what may be thought, I am not anti alternative engines. These forums are full of older posts I have made regarding the subject, so I wont bother repeating any of it (and causing this thread to drift off the cliff any further after this).


What I am a big proponent of is full disclosure of the real world experience that experimenters have... all of the good and the bad.
That comes from years (decades actually) of dealing with RV builders via tech support and seeing the aftermath that results from them not going deep enough with there research.

If a subi engine installation can be done that results in an airplane with a power to weight ratio that is equal to that of a Lycoming, then the far right side of the experimental movement has failed a lot of people because there is tons of evidence to show that if it is being done successfully, only a small percentage that try are able to find the holy grail they seek.

If it is something easily within reach there must be a serious break down within the experimental culture.....

Scott, you asked me to take the Rotax 912iS increased cooling requirements at face value a couple months back where your comments made no logical sense and you said you couldn't provide details to back up your statements.

Deej provided you with a item by item breakdown of weight yet you immediately discounted those figures. You also took the opportunity to start the usual war against alternative engines against a post from a new member and what was hoped to be an interesting and informative thread for many others here on VAF. As Deej asked- what is your point? Hardly welcoming.

I did a side by side comparison in the April 2005 Kitplanes pitting my 6A against Les Davenport's 360/ Hartzell RV6A. At the time of test, I weighed about 35 more pounds than Les' empty. Performance was pretty comparable as I outlined in the article. I was as curious as everyone else in how they would compare and figured a side by side was the best way to judge that. Those who may be interested can read about the test near the end of this page: http://www.sdsefi.com/rv14.htm

I can see from your many posts you feel everyone should have a Lycoming in their RV. That's fine. Your opinion is crystal clear. We got it.

Can we get this thread back on track if the OP has not been scared away already?
 
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Scott, you asked me to take the Rotax 912iS increased cooling requirements at face value a couple months back where your comments made no logical sense and you said you couldn't provide details to back up your statements.
What I did actually say was that the U.S. representatives of Rotax (the ones that work directly with OEM customers) actually advise OEM customers that it will require more cooling system capabilities. And I also said that I myself didn't understand the scientific reasons for it, but that doesn't mean it is not real. If you are not willing to accept that, it is your prerogative. What would be my motive for making that up? Unless you assume that it implies an improperly engineered engine installation. If that were the case then all the OEM customers are making the same mistakes (including the designer and manufacturer of the engine).


I can see from your many posts you feel everyone should have a Lycoming in their RV. That's fine. Your opinion is crystal clear. We got it.

Actually it is crystal clear that you don't, but I will refrain from any further thread drift.....
 
As we've seen countless times, some folks will take pretty well any opportunity to diss alternative engines, for any reason. .

There are a lot of negative views out there on auto conversions for the simple reason that so many people have had negative experiences using them. RV builders who have gone down that road without success (and that's most of them) are often the most strident critics of auto conversions. It's a very expensive and massively time consuming FWF exercise to have to remove an auto conversion and replace it with a Lycoming as so many have been forced to do to achieve reasonable reliability.

A very good friend of mine ripped out the auto conversion in his RV6A and replaced it with a Lycoming. After years of never-ending issues with the gear box, the engine management system and cooling problems he finally gave up and bit the bullet. It cost him a pile of money and in the end he became a very vocal critic of auto conversions.

We all know of similar instances whereby RV builders have converted from auto-conversions to Lycomings....but I've never heard of a single instance of anyone ripping out a Lycoming to replace it with an auto-conversion. That might be a point worth thinking about for those contemplating sipping the auto-conversion Kool-Aid.
 
I've been trying to stay out of this thread, but I really hate to see some of the discussions dive into personal attacks. Let's face it, the automotive vs. aircraft engine discussions rank right up there with the primer wars.

I think what sometimes gets in the way of thinking is that there is a problem to be solved, perceived or otherwise. In the case of Van's airplanes, they were designed and optimized for Lycoming engines. That's why they perform so well using the recommended power plant. :)

Now, if per chance there was an airplane that was clean-sheet designed for an automotive engine, well it just might work. And it might work better than installing an aircraft engine on it.

But for those who like to experiment, and the track record does show that automotive engines on aircraft designed for aircraft engines might suffer in the form of performance or reliability, we shouldn't hold them back. Educate them with the facts in that their performance WILL be different. Different doesn't always mean bad to everyone.

But having the same expectations as the rest of the Van's fleet has with regards to performance and reliability could be a stretch.

Some may just like to tinker, realizing there is not a problem to be solved. We can all argue about perceived costs, but again, the airplanes were designed for the Lycoming engines. And almost 10,000 flying airplanes kinda prove that something is working well.

My hat is off to those who continue to experiment. Let's help them, rather than polarize our community. :)

Vic
 
Ditto what Vic says!

I've said this before, but it's worth repeating. I'm all for alternative engines. I've built two, an RV9 and a Sportsman, with diesels. I've shared the good and the bad (with the RV9; The Sportsman has had no bad to share). Both have 500+ hours on them. Performance is equal to their Lycoming counterparts, with less fuel burn. The RV9 is lighter than the equivalent Lycoming, and the Sportsman is heavier. I'm happy.

What rubs folks wrong is, as Ross points out, is that any discussion on alt engines always degrades to a thread promoting Lycomings and bashing alternatives. I think we understand why: Because Lycoming is the "standard", everything else is judged against it. Fair enough. And because Lycoming is the "standard", all of the faults associated with Lycoming are also "standard". Everyone just accepts those faults because they're commonly known and commonly dealt with. This leaves an open door for Alternative engine bashing because they're different and they have different challenges associated with them.

As alternative engine experimenters deal with challenges, there is a lot higher risk of failure. As long as the "Alternative Engine Experimenter" is fully aware of the risks, is willing to accept them, and has the skills to deal with them, I say good for them; go for it. But when folks go that route thinking they're going to save money or time, or somehow have something more "modern" than a Lycoming, without understanding the pitfalls, then I think it's a good thing that these threads exist. People considering alt engines need to go into it with their eyes as wide open as possible, and be realistic about what they're getting into. We've seen in the past how certain companies have put shiny packages together and lured unsuspecting buyers into believing they'll end up with more "modern, cheap, reliable, smooth, quiet" etc, and it just hasn't turned out so well in many cases. At least by reading these threads, people cannot say they were't forewarned.

So I hope that we can stay civil as we make our points, not driving away those who share their experiences with alt engines. I, for one, am always very interested in learning from others' experiences and ideas. I truly enjoy seeing creativity and craftsmanship in something different than the "standard". There are many of us that simply enjoy trying something different, and sometimes it turns out well. Heck, if we keep at it long enough, someone might even come up with something better than a Lycoming! Not a bad thing.

Kurt Goodfellow
 
LS1

I would really like to know more about the RV7 that this thread began with what a cool setup sort of like those 3/4 Mustangs at Reno .Sort of like putting the Exp in Exp aircraft .I bet you could get around 300hp direct drive LS2 at less than 3000rpm .Sure would be a great thread with no bickering from the usual experts.
Bob
 
In for an ounce, in for a pound.

I am having visions about using an F1 Rocket as a starting point and stuffing an LT 4 (650 HP supercharged ZO-6 engine) partway into a deeply concave firewall to keep the C of G manageable. The pilot would move to the back seat and the front seat would be gone. P51 style rad and scoop below. Bruce B would be taking another run at the altitude record if you put full length -4 wings on it.

It should be lighter than a 540 Rocket with 2 guys.
 
I am having visions about using an F1 Rocket as a starting point and stuffing an LT 4 (650 HP supercharged ZO-6 engine) partway into a deeply concave firewall to keep the C of G manageable. The pilot would move to the back seat and the front seat would be gone. P51 style rad and scoop below. Bruce B would be taking another run at the altitude record if you put full length -4 wings on it.

It should be lighter than a 540 Rocket with 2 guys.

Or, you could save a couple hundred pounds with...
https://www.youtube.com/watch?v=0LFXE6EBLLs

(Please note that the guy who posted the video isn't the guy who actually built the plane, even though he likes to pretend he is...)

edit: I think they've already unofficially beat the *unlimited* time to climb record to 10k feet (with a fixed pitch prop on the RV).
 
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As a diversion from our little discussion, I thought I'd mention something from my past.

When I was in high school, I thought that my HS could use a field goal kicker. So I gave it a try. Discovered I just couldn't do it. So all of my friends tried, and they couldn't do it, either.

So, it became obvious to me that kicking field goals just isn't possible, since neither I, nor anyone I knew, was able to do it successfully, though many tried and failed. Now, whenever the subject of field goals come up, I just say to give it up; it will never happen. It can't be done, and only fools would try.

Just thought you all should know, in case you had some foolish notion that you'd try to kick field goals.

Charlie
 
I would really like to know more about the RV7 that this thread began with what a cool setup sort of like those 3/4 Mustangs at Reno .Sort of like putting the Exp in Exp aircraft .I bet you could get around 300hp direct drive LS2 at less than 3000rpm .Sure would be a great thread with no bickering from the usual experts.
Bob

+1, well said.

Personally, I am particularly hoping for reliable, well engineered and tested geared engines, filling the gap between the Rotax 912 and the O-320. For some reason, none of the big players seem to have any interest in stepping in.

I am also not concerned about the auto engine itself, more about the added components (e. g. gearbox) and the engineering and testing associated with it. If it's done right, I don't see why a auto engine conversion couldn't be just as reliable as a 'real' aircraft engine. The engineering and testing part however seems to be an almost impossible hurdle to overcome for small companies.

Btw.: Our Lycoming IO360 recently developed two cracks in the crankcase. :mad: It was apparently caused by a bad cast, something that can only extremely rarely be found in an high volume automotive series production.
 
I used to have a 79 Camera, the engine and everything else was so troublesome that I would not use a Chevy engine to power my wheelbarrow.
 
When it comes to an LSX in an RV, I think we have to realize that the installation is likely to weigh in excess of 500 pounds with a gearbox. Yes, this can and has been fitted to an RV7 and some RV10s but will certainly require some mods to the aiframe and some re-thinking to maintain decent C of G ranges.

These are some of the questions I'd like to know the answers to from the OP.

As I said, I have a number of customers flying these engines in other airframes successfully. One will be supplying FF engine packages in 2018 and another is using the engine to power their new kit aircraft which has been flying for a couple years and should be on the market in late 2018 or early 2019.

The cost per hp and weight per hp is hard to beat on this engine if your design can accept that 500ish lb engine weight.
 
I am also not concerned about the auto engine itself, more about the added components (e. g. gearbox) and the engineering and testing associated with it. If it's done right, I don't see why a auto engine conversion couldn't be just as reliable as a 'real' aircraft engine. The engineering and testing part however seems to be an almost impossible hurdle to overcome for small companies.

No, it is not impossible. To be blunt, engineering and test doesn't get done because most of the folks doing them are ignorant in the dictionary sense (i.e. simply lack the required knowledge), and/or just blow it off.

I've been interested in alternative engines since the mid-90's. I knew a lot about engines, so how hard could it be? Bought a "tested" drive from a vendor, which turned out to be a mess in multiple areas.

Fast forward. After OSH 98 we measured and modeled the old drive, did a torsional analysis, tweaked the model inputs for a better result, designed a drive to match the new model, built that drive, and conducted live torsional telemetry for comparison to the computer model...tied to a truck in front of my hangar, with an obsolete FM transmitter, a cast off o-scope, and a Fluke multimeter. Crappy equipment, but we got great data, so much so that we designed a viscous torsional damper for the drive, then built and tested it, further reducing measured shaft and belt loads. When I flew it to S&F in the spring of 2000 I knew exactly what was going on up front. The Wheatstone bridge was still glued to the propshaft, protected by a strip of duct tape...which almost nobody asked about.

I was lucky; "we" included my friend and mentor Steve Crow, a very, very smart guy, so I had a huge push up the learning curve. Thanks Steve.

Point is, first, it required knowledge, deep knowledge, in an area totally unfamiliar to the average well-qualified builder. I simply didn't know what I didn't know, and what was on the message boards back then was mostly BS (still is). Second, it required a lot of work. But third, tools were available, it didn't require cubic dollars, and 90's was the Dark Ages compared to the tools available today. Remember, this was just two guys, with one at long distance.

Look around. Alt engines have already entered the mainstream. For example, Continental now says there are about 5000 Mercedes-based diesels out there. They're certified, the CD-135 and CD-155. Yep, the early ones were a mess...but you don't hear much about them now. The factory is all in, with committed engineers doing the work, getting the data, making the improvements. That's what it takes. Check back in another 10 years.

If a guy wants to "experiment" with TLAR design, then do the break, fix, break, fix routine until he has a useful system, well, fine. It's not a lot better than the 1000 Monkeys Method, but given enough time and effort it can work. Hopefully the guy is having fun with the challenge, but I assure you, the engineering and measurement method is just as much fun, and a whole lot more successful.

I have a real jones with vendors who use the Monkeys Method with customers, while convincing them they are "experimenting". Kurt covered that very well. If the customers really know what they're getting into, fine, but most don't.

Not to kick the dead, but I once walked down the road at S&F while having a conversation with Bud Warren, who informed me that "All that torsional stuff is just bulls####. I don't even think it exists." Kinda made my head spin, but it didn't seem like there was any point in trying to convince him. That's EAB.
 
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I'll agree with Dan here. Even in this day and age of relatively cheap diagnostic electronics to do TV studies, most would-be engine vendors don't bother with such studies. In most cases, this would save testing time and money.

Let's face it, until you have at least 250 flight hours on an engine package with nothing breaking and wearing appreciably, can you even start to say that the package MIGHT be safe enough for general consumption. That takes a while and a lot of fuel to accomplish and you still don't know if something might be lurking down the road.

It does seem that most prefer to just start flying and see if anything breaks and that's probably fine for the one-offs where you are only risking your own life.

Certainly in the end, you'll still have to get the flight hours on the prototype or a fleet of them to prove it all really works as advertised. Be prepared for those costs and time if you plan to be a FF package vendor.

I might add that there is far more to prove on a FF conversion than just that TV issues won't break something and the best way to do this is many flight hours.
 
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No, it is not impossible. To be blunt, engineering and test doesn't get done because most of the folks doing them are ignorant in the dictionary sense (i.e. simply lack the required knowledge), and/or just blow it off.

I've been interested in alternative engines since the mid-90's. I knew a lot about engines, so how hard could it be? Bought a "tested" drive from a vendor, which turned out to be a mess in multiple areas.

Fast forward. After OSH 98 we measured and modeled the old drive, did a torsional analysis, tweaked the model inputs for a better result, designed a drive to match the new model, built that drive, and conducted live torsional telemetry for comparison to the computer model...tied to a truck in front of my hangar, with an obsolete FM transmitter, a cast off o-scope, and a Fluke multimeter. Crappy equipment, but we got great data, so much so that we designed a viscous torsional damper for the drive, then built and tested it, further reducing measured shaft and belt loads. When I flew it to S&F in the spring of 2000 I knew exactly what was going on up front. The Wheatstone bridge was still glued to the propshaft, protected by a strip of duct tape...which almost nobody asked about.

I was lucky; "we" included my friend and mentor Steve Crow, a very, very smart guy, so I had a huge push up the learning curve. Thanks Steve.

Point is, first, it required knowledge, deep knowledge, in an area totally unfamiliar to the average well-qualified builder. I simply didn't know what I didn't know, and what was on the message boards back then was mostly BS (still is). Second, it required a lot of work. But third, tools were available, it didn't require cubic dollars, and 90's was the Dark Ages compared to the tools available today. Remember, this was just two guys, with one at long distance.

Look around. Alt engines have already entered the mainstream. For example, Continental now says there are about 5000 Mercedes-based diesels out there. They're certified, the CD-135 and CD-155. Yep, the early ones were a mess...but you don't hear much about them now. The factory is all in, with committed engineers doing the work, getting the data, making the improvements. That's what it takes. Check back in another 10 years.

If a guy wants to "experiment" with TLAR design, then do the break, fix, break, fix routine until he has a useful system, well, fine. It's not a lot better than the 1000 Monkeys Method, but given enough time and effort it can work. Hopefully the guy is having fun with the challenge, but I assure you, the engineering and measurement method is just as much fun, and a whole lot more successful.

I have a real jones with vendors who use the Monkeys Method with customers, while convincing them they are "experimenting". Kurt covered that very well. If the customers really know what they're getting into, fine, but most don't.

Not to kick the dead, but I once walked down the road at S&F while having a conversation with Bud Warren, who informed me that "All that torsional stuff is just bulls####. I don't even think it exists." Kinda made my head spin, but it didn't seem like there was any point in trying to convince him. That's EAB.


If there was a LIKE button I would have pushed it
 
I think the Motus V4 motorcycle engine would be good for the 2 seat RV's. 160hp & 180hp versions weighing 150lbs for the engine only. This engine is being used in the Switchblade flying car. Seems like a better place to start than a heavy V8. The cost may be high, I don't know. Of course some sort of reduction drive would need to be developed, as well as other systems. True engineering development of a reduction drive is complicated - just look at the geared engine development during WWII - that took a lot of time, money, and engines. Still, this engine may be a good choice.
 
To throw some more gas on this fire in the form of ENCOURAGEMENT, sometimes an airplane can be made to perform better on an engine that is different than the original. The best example I can think of is the North American P-51 Mustang. Originally flown with the Allison engine, it became a real thoroughbred once the British mated it to the Rolls Royce Merlin engine.
Of course it was War, and costs were not a factor. :)

Vic
 
LS1- RV7

Good Day all,

Im the new owner of the black lawn dart with the ls1 in it. Feel free to ask any questions.

I love this thing
 
Good Day all,

Im the new owner of the black lawn dart with the ls1 in it. Feel free to ask any questions.
I love this thing
Talking RV7A N577AZ shown in #10 in this thread? Cool
What is empty weight?
Top speed?
Cruise Speed and FF?
PSRU brand/make and Prop?
 
The LS-1 plane has been parked outside @ X50 in Florida for at least a couple of months. I have not seen it fly.
 
Maybe 15 years ago, back when I still lived in Arizona and was still writing for Kitplanes, I had heard about an RV with a V-8. As I recall, and it's been a few years now, I came across this airplane at some airport and talked to the owner. The plane was gorgeous, he had a trophy wife/girlfriend, and he told me that he routinely cruised at redline at altitude. Don't recall the discussions about gross weight. I did not tell him that I wrote for Kitplanes.

I told Marc Cook, editor back then, of this encounter, and that I was no longer interested in writing the story. He concurred.

A year or two later, that plane was destroyed in a fatal accident.
 
GMC, he responded to me on YouTube.. Empty weight of 1412, fueled up at 1664, gross weight of 2400 (yikes) pounds!
 
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