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ScaleBirdsScott

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Now my point here is that this airplane was originally designed for a 100hp 140lb engine. It has had Suzuki and Honda 6 cylinder engines installed in versions of it and now is working toward an appx 400hp 600lb LS3. I think it demonstrates there is a wide spectrum of engine choices which would work in not only the Titan but most any other homebuilt. The key criteria before making any choice is weight. I don't care what any engine is capable of power wise, first it must meet the maximum weight the cg can handle. So, someone who is building a similar airplane but doesn't have the deep pockets of a TFG could build a perfectly acceptable airplane with a stock 430hp LS3 and have 160 hp @ 2400 and 220 hp @ 3200 and use a 2 or 3 blade prop.
Without increasing weight a stock LS3 480 would supply 250hp @ only 3000 rpms. Now any airplane that can carry the weight of an LS3 can have 250hp @ a usable 3000 rpms. Why would most builders need a reduction drive when very very few would ever need more than the LS can supply usuably in direct drive. Expense is cut way down. Weight is lessened. There are fewer parts to fail and less chance of a harmonic issue.
If someones airplane cannot handle the weight then they move to a lighter and less powerful direct drive or a much lighter and smaller engine with a redrive. You have to compare wt/hp available whether its a redrive or not...THEN compare cost and complexity. There is a broad range from 180hp to 300 hp where a direct drive LS engine fits in just fine.........but the popular thing seems to be buying a redrive for all LS conversions rather than just when needed.
First, the Rotax on a T-51 is hanging way out in the nose (and has a gearbox BTW so it's revving super fast to get the good power/weight it has) Meanwhile if you look at an LS install on a T-51 that engine is buried back into the firewall. They share the same name, but a hotrod T-51 nowadays is not the same aircraft as one that's been rigged for LSA with the 912. Different landing gear, changes to the structure, the wing is completely different, the entire W&B is completely different. It's a heavier, more robust aircraft because it's dealing with more weight and a lot more power. You cannot simply say "I'll take the power output of an LSA Rotax powered T-51, but put it on the airframe with the all of the weight of one designed to fly with literally 4x the power.

So the idea that "very very few would ever need more than the LS can supply usuably in direct drive" is, I dunno, a total fallacy? An aircraft with 4-500 hp might indeed be a hotter ship than one designed for 120-180hp, but taking an aircraft tuned to fly at 4-500hp and giving it only 180 doesn't make it better for people who can't handle a hotrod. It just makes it likely dangerously underpowered for its bulk. If you want an aircraft made for 180hp or less as a 'common man's easy to fly beast' then it needs to stay light so that it still can climb out and perform with that power range. I'd say you want an engine under 300lbs.

Second, I can't follow all your math comparing things here but, your weight delta between an LS3 direct drive with 30lbs of front end bell housing, and an LS3 with a 85lb gearbox is, if I'm interpreting things, 55lbs. For a difference in performance of 250+ hp.

In my world of direct-drive radials (I'm all for the merits of direct drive BTW) if I could gain 10-20 hp with the addition of 10-20lbs I'd do it. Easy choice. If I could add a 80-lb gearbox and make a 9-cylinder radial that puts out 160hp into one that generates 250hp I'd still call that an absolute win. But these radials aren't designed to run any faster than their current RPM range so the gearbox gains me almost nothing. The LS engines are absolutely meant to go to higher RPM and so kneecapping it doesn't serve any good purpose.

The only valid reason to choose an LS engine and not put a gearbox on, is straight up cost. It's dirt cheap dirty power. If you want safety and simplicity, get an O-540. If you want performance, get a gearbox. If you want low cost... I guess an LS maybe? Or find a used O-540 or even an IO-360 or similar for probably about the same price.

Only other case is if you have an actual 1930's era design you're building an experimental replica of, that indeed is designed for flying around on 200hp with a 450lb engine, and you don't want the risks and costs of rebuilding an actual old motor.
 

pfarber

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So the idea that "very very few would ever need more than the LS can supply usuably in direct drive" is, I dunno, a total fallacy?
What E/ABs need this? You say its a fallacy but I can't think of any mainstream (aka popular) HB's that need 400+ HP.

GA lives between 100-200HP, the sweet spot is 150-180hp.

The LS engine is to heavy, direct or geared, for 90% of the E/ABs out there.

Get me a 180-200hp direct dive engine that's less than 300lbs, then you have my attention.

Edit: And isn't over $10k installed.
 

ScaleBirdsScott

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You answered your own question, I think.

90% of homebuilt aircraft don't need 400+HP

And 90% of homebuilt aircraft can't handle a 400lb engine hanging off the firewall, such as an automotive V8.

My point is if your airframe can comfortably haul around a 400+lb engine then you almost certainly are talking about a serious flying machine, or a very old flying machine. In either case, it's automatically out of the range of mainstream E/AB. And with that sort of weight, you'd better have that engine producing as much power as you can to keep that engine and everything attached to it in the air.

So back to gearboxes, which is a common solution for engines whether they're 10hp or 10,000hp, it's not like they are black magic. The only risk factor that adding 2-3 gears in between the driveshaft and the swingy blade bits adds is that someone needs to do the maths, and people need to respect those maths. If the gears are meant to be lubricated a certain way, and to handle no more than a certain load from the propeller, and a certain weight, and so-on... know what that is, and obey the limits.

I'm going to be looking at some 4-cylinder engines with a gearbox within the next 6 months for our next aircraft most likely; when I do I'm going to make sure the person making the PSRU knows their stuff and can recommend a prop or at least evaluate whatever propeller we choose. I'm going to make sure that if they have a proposed lubrication schedule we have a way to stick to it, and hopefully there's a way to ensure through early stages of flight testing that we can check for wear and so-on.

If there's other stuff we should be checking I'm sure to figure it out.

I have been a fan of direct drive and I've been extolling their virtues for a few years now; so I'm certainly up on the benefits. I'd be all for a direct drive simplicity with large displacement and low RPM. I'd love a V6 or V8 if it had the displacement for direct drive, had the weight of 250lb or less, put out 160-180hp, and cost under $10k. I'd drop everything to help that come to market. It would fit a lot of warbird type cowls and look awesome. But I'm certainly not expecting such a beast to ever be made. (And if it were, lets be honest, most people would still throw a gearbox on it, easily push the engine to 5000 rpm, and gain plenty more power.)

So screw it, I'd even take a 250lb V6 with a gearbox if it was getting that 130-160 @ 4-5000 rpm, even if it cost $20k, that would be great. Still don't expect that to ever see market either.

Maybe in 10 years I'll learn enough about making engines to hire the people who know even more about engines to make it happen. Or I'll just find that, hey, electric is all we need.
 

AdrianS

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The issue with PSRUs is torsional vibration. If your system goes resonant, the torque peaks are huge.

My experience is with dynamometers, and I've seen a 3 cylinder diesel shear a drive shaft on a dyno that would easily hold a 700 hp v8.

There's a company that we've used that supply TV dampers for engine dynos; they need to know:

Crank & Flywheel inertia
Driven inertia
#cylinders
Firing order

and a bunch of other things, as well as the usual torque & rpm, before they will supply the coupling.

Just bolting a soft coupling (ie pin and bush) in line is not a good idea. Been there, done that, heard the bang ;).
 

Winginitt

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First, the Rotax on a T-51 is hanging way out in the nose (and has a gearbox BTW so it's revving super fast to get the good power/weight it has) Meanwhile if you look at an LS install on a T-51 that engine is buried back into the firewall(?). They share the same name, but a hotrod T-51 nowadays is not the same aircraft as one that's been rigged for LSA with the 912. Different landing gear, changes to the structure, the wing is completely different(?), the entire W&B is completely different. It's a heavier, more robust aircraft because it's dealing with more weight and a lot more power. You cannot simply say "I'll take the power output of an LSA Rotax powered T-51, but put it on the airframe with the all of the weight of one designed to fly with literally 4x the power.
(Note: I saw nothing on the website to verify these statements)

The airplane is sold as a 3/4 scale of the original. If thats correct, the fuselage and wings and tail would be the same size no matter what engine is installed in it. I think the original version was powered by a Rotax and had fixed landing gear. As they decided to add more power, they obviously had to add some more strength, but the external size per their website shows a "one size fits all" specification for size.....only weight varies. So when you are landing, the lift available is not getting better when you add the weight of the engine, the redrive, the stronger mount, the retractable landing gear. It also says it has a scale 4 blade propeller. If you click on the attachment below, you will find that Titan once flatly stated on page 15 : Engines that are not appropriate for the T-51 airframe: Four and six cylinder opposed Lycoming or Continental engines are too wide to fit inside the airframe. Big V8 engines like the Chevrolet or Ford are too heavy and too large.
They further stated: Some considerations should be physical size and weight of the engine. The engine compartment width is about 23 ½ inches. The length is about 32 inches. The height is about 35 inches at the back and about 30 inches at the front. The weight should be limited to about 250 lbs. If the engine is heavier than 250 lbs., some structural modifications will need to be made forward of the cockpit. Also, some weight needs to be moved aft. Moving the battery is probably a good place to start, although that may not be enough.
https://web.archive.org/web/20101129151738/http://titanaircraft.com/files/t-51_brochure.pdf


[QUOTE="ScaleBirdsScott, post: 500383, member: 37379"]So the idea that "very very few would ever need more than the LS can supply usuably in direct drive" is, I dunno, a total fallacy? An aircraft with 4-500 hp might indeed be a hotter ship than one designed for 120-180hp, but taking an aircraft tuned to fly at 4-500hp and giving it only 180 doesn't make it better for people who can't handle a hotrod. It just makes it likely dangerously underpowered for its bulk. If you want an aircraft made for 180hp or less as a 'common man's easy to fly beast' then it needs to stay light so that it still can climb out and perform with that power range. I'd say you want an engine under 300lbs.[/QUOTE]

You stated that the LS engine gets moved "way back" in the engine compartment. I have an LS3, and its 26" long not counting the flywheel. If you add a reduction drive that pretty well takes up the quoted 32 inch length. I'm reasonably sure that a Rotax powered version sits farther forward due to its compact size and weight, but I would guess that the CG changes a lot with an LS and redrive. A properly built LS engine can provide 300hp @ 3000 rpms. (Note: If I converted correctly, I believe the 912 Rotax is about 28 inches long.)

So the idea that "very very few would ever need more than the LS can supply usuably in direct drive" is, I dunno, a total fallacy? An aircraft with 4-500 hp might indeed be a hotter ship than one designed for 120-180hp, but taking an aircraft tuned to fly at 4-500hp and giving it only 180 doesn't make it better for people who can't handle a hotrod. It just makes it likely dangerously underpowered for its bulk. If you want an aircraft made for 180hp or less as a 'common man's easy to fly beast' then it needs to stay light so that it still can climb out and perform with that power range. I'd say you want an engine under 300lbs.
What percentage of home built airplanes do you feel employ an engine using over the 300 hp an LS can provide without a redrive ? Did you ever read Ben Haas's experience with having too much HP ?
The airplane is "tuned" to fly with lots of different HP engines. One of the most common is a 245 HP Honda conversion. A properly built LS engine can provide 300hp @ 3000 rpms. A stock
LS3/480 provides 250 hp at 3000 rpms. I think a direct drive LS would compare very favorably with a 245 HP Honda with a redrive both weight and HP wise. Its components would all be under far less stress and it would have less tendency for harmonics due more evenly distributed power pulses. Probably cost less too. I'm surprised that you would make statements like "total fallacy" and "dangerously underpowered" when the company already has lesser powered LS engines and Honda engines out on the market and their airplanes are flying just fine with them. In fact they even state a max of 300hp on their website. http://titanaircraft.com/t51D.php

Second, I can't follow all your math comparing things here but, your weight delta between an LS3 direct drive with 30lbs of front end bell housing, and an LS3 with a 85lb gearbox is, if I'm interpreting things, 55lbs. For a difference in performance of 250+ hp.
The resultant HP gain per the added weight is quite an argument for HP/LB though.
I think that pretty clearly says that I agree that the amount of horsepower vs the weight of the redrive is a major consideration. What you aren't listening about is that no matter what the hp to weight ratio is, weight on the nose of an airplane is still weight, and some airplanes cannot deal with the additional weight of a redrive. It also doesn't do anyone any good to have 400 hp if their airplane isn't capable of using 400hp. Again, I point to Ben Hass's experience with having an overpowered airplane.

n my world of direct-drive radials (I'm all for the merits of direct drive BTW) if I could gain 10-20 hp with the addition of 10-20lbs I'd do it. Easy choice. If I could add a 80-lb gearbox and make a 9-cylinder radial that puts out 160hp into one that generates 250hp I'd still call that an absolute win. But these radials aren't designed to run any faster than their current RPM range so the gearbox gains me almost nothing. The LS engines are absolutely meant to go to higher RPM and so kneecapping it doesn't serve any good purpose.


Thats one way to look at it, but its not the best way. You know as well as I do that when an engine is run at higher rpms the stress on all its parts goes up exponentially and since the engine goes thru more cycles per second its life is shortened by wear. Both things are undesirable. GM tested some of these engines for months on end at high rpms and they survived, so they have "capability" to possibly do that. I wouldn't want to bet the farm, much less my life that it will work 100% of the time in an airplane. People talk about "piston speed" as the only consideration, but you also have to consider the valve springs, the alternator,the valves, rings, injector cycles,spark plugs, water pump, sensor life.....
If you think 4000 rpms isn't hard on an engine, put your car in first gear and drive just 5 miles @ 4000 rpms. While car engines will run at elevated rpms for quite some time, you will find that todays vehicles usually hover somewhere around a liesurely 2000 rpms on the highway and thats a whole lot closer to what a propeller uses too. Double the rpms and you exponentially increase the stresses.....not just double them. So the purpose it serves is reliability, longer life, and better economy besides saving the high cost of a redrive. While todays engines are capable of higher rpms they are designed to survive by normally ONLY running in the 2000 rpm range during long drives.

The only valid reason to choose an LS engine and not put a gearbox on, is straight up cost. It's dirt cheap dirty power. If you want safety and simplicity, get an O-540. If you want performance, get a gearbox. If you want low cost... I guess an LS maybe? Or find a used O-540 or even an IO-360 or similar for probably about the same price.
Priced any O-540s recently ? It will cost more than the home shop you want to have and then every year after that you will pay thru the nose to maintain it. Its already been proven that automobiles are more reliable than aero engines. The problem is almost never that the auto engine failed.....its usually the peripheral stuff. With aero engines, they maintain their reliability by throwing money at them every year with inspections and parts replacement......auto engines not so much.
 

Winginitt

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So screw it, I'd even take a 250lb V6 with a gearbox if it was getting that 130-160 @ 4-5000 rpm, even if it cost $20k, that would be great. Still don't expect that to ever see market either.
Here are 3 and there are a lot more.

You need to get out more and maybe read some old issues of Contact magazine.....maybe even buy the books they offered if they are still available. I think you might find it enlightening to see pictures of the Belted Air Power conversions.....they already did that 30 years ago along with a host of other builders and grass roots companies. And it doesn't cost $20K.

4.3 V6  Mustang 002.jpg Velocity 002.jpg Bellanca V6.jpg
 

ScaleBirdsScott

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There's a lot of interesting points there. So my one flaw in my argument has been that I'm assuming Titan is still trying to get 425+ HP out of their LS conversions, and so they would have balanced their weight around the idea that they're using all of that 425+ hp to maintain the performance with such an engine. But it seems, however, that they're derating the engines to around 310hp with the gearbox so it's back to being on par with the Honda builds; And they're just eating the extra weight of the LS vs the Honda since, apparently, 300-ish HP is plenty enough for the airframe to carry around a 900lb useful load, and an extra 100lbs worth of engine weight is fine since it's cheaper, sounds better, and runs lower RPM regardless.

In any case, I've been following the Titan since about 2011, and have been to their shop and seen their various models at shows. Note that the brochure being linked is literally from the wayback machine c. 2010 so, maybe some things have changed in the interim. Titan's attitude was not to put big heavy stuff on the front. Until people kept doing it and lo-and-behold the thing flew pretty good. There's even a T-51 with a V-12 engine on the front. I'm sure that puts out some grunt. They've shortened wings for the higher-power versions, changed airfoils, and so-on. Some of them are built to prioritize safe handling, others top speed. There's no one T-51 Mustang, any more than there's no one Ford Mustang. Over the last 10 years looking for the ideal mix of features it's certainly evolved but you won't see that just from the website.

But lets look at some specs:

Empty Weight: 850 - 1,350 lb
Gross Weight: 1,320 - 2,250 lbs

We can assume the lowest number is the LSA version configured to be balanced by the Rotax. We can assume the higher number is the ship built to handle the V8. Lets say a 912 is 170lbs and a LS with their GB is 470lbs, that's a difference of 3000 lbs. Yet, the empty weight is a difference of 500lbs so there's at least 200lbs of extra structure and so-on added to handle simply the weight and power of a V8 over a Rotax. In any case, the useful load on the Rotax version is around 470lbs while the useful on the V8 with Gearbox is up around 900lbs. So the T-51 with V8 is rated to haul around 1000lbs more aircraft (500 of that being the aircraft and engine itself) than the Rotax version, With an engine getting what in one article claims is a derated 310hp at the prop.

If that's true, and a direct drive V8 could swing the same prop and generate roughly the same 300hp within a safe RPM range, I'd consider that actually a pretty good case for exploring the direct-drive.

(The other consideration with a PSRU however is that you can drop the prop speed even further. What about running the engine at 3000 RPM but swinging the prop at 2000? That's suddenly a nice big paddle moving a lot of air. Particularly for the replicas, that's also a big consideration. But it's not a requirement so it's a bit of a side issue.)

Back to the T-51, at this point each machine is using more-or-less the same overall sizing due to a common welding jig for the frame; but otherwise I would wager very few T-51 builds have the exact same configurations. Guys are putting all sorts of combinations together. I'm not a customer though, so maybe those who have more regular and first-hand contact can shed some light. I may even recall that the firewall itself has moved back over the years? In general looking back to specs from 10 years ago, or even just the Titan website today, doesn't really convey the whole story of the aircraft. There's been a lot of good development over the last 15-20 years.

In any case on the V8 installs of the T-51, the engine is indeed hanging back right against the firewall. The mini-merlin installs do the same thing from what I've seen, but the engine mounts aren't as heavy duty and there's a little more room all around. It's all simple stuff, trying to pull that weight rearwards towards the CG. But yes in this case, weight is weight. I just think, hey, we're talking about big engines here so 50 lbs one way or the other isn't make or break apparently.



When I'm talking about an available engine in any case, it needs to be at least somewhat commercially available: ie. Aeromomentum, Viking, Rotax, AutoPSRU's, Titan, etc. If the host engine isn't a currently in production auto engine (unless there's just countless stores of well-kept old stock waiting for a new purpose) and the gearbox and conversion package isn't a turn-key, off the shelf unit, it's not something anyone can design around for anything but a one off. And if there's a company I missed in the last 10 years who can sell me, you, and 100 other people year in and year out, a brand new V-type engine, with a well engineered gearbox for spinning a propeller, that can do 150-250hp or anything in that range, for under $20k, I don't know why they have worse marketing than even I do; cuz I havn't heard of it.

Now, thinking about it more, the Titan Mini Merlin V6 might in fact be right in that range. I think it's a bit heavy for my design still, we're really looking to max out around 250lbs and 150hp. But for other people just looking for that holy grail little engine I feel like they could do more with that V6. I wish I could find out: They don't advertise the engine very well on the Titan website. I'm sure they don't want to deal with non T-51 installs because it's a lot of headache.

In any case, pricing shows the V6 costs $11,6k while the conversion kit with gearbox is $25k. Meanwhile the LS is $7k and the conversion kit is still 25k. So clearly most people seem to prefer to pay less and get more power, despite the weight penalties.

And by the same token, when suggesting a Lycoming I'm talking about a used but good condition one like some homebuilders do, and in that case you can certainly get one of those for under the 30+ a Titan engine would cost. (And that'd be about on par with the entry level cost of the Haas I need ;))

Not that it would fit the T-51, but, some hypothetical other design where it's relevant.
 

Andreas K

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I was flying a RV-10 with a LS-7 engine and an old style (casted case) Bud Warren PSRU. The PSRU failed after 33 hrs. The output shaft to the prop broke. I don't know the exact cause. I loved the engine and the performance.
The reason I bought that PSRU was the track record of 700 hrs that Bud had on his own airplane. One thing you should ask your PSRU manufacturer is the G-limit of that PSRU. I made a 3.5 G turn once and that could have been the cause. Anyway. Now I am flying with an IO 540 which is 10 knots slower, uses more gas, needs pre-heating, uses 1 qt. of oil every 10 hours and weighs 140 lbs less. For a family hauler I should have gone with an IO-540 from the beginning.
 

Winginitt

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The post above by Andreas is a perfect example of the mystery of using a reduction gear. The reduction gear had a good reputation on the designers personal airplane. Everything was fine....until it wasn't. Now, though he seems to prefer the LS engine, he has soured on the set up and gone back to an aero engine. One failed redrive carries a lot of weight in future sales and drives people away from conversions.......and the general message is......."another engine conversion failed". It should be the"redrive failed". I think there was a lot more success with low and mid-power range reduction drives, and as you increase the power levels things become more difficult. Thats an opinion, not a proven fact. I have to wonder if the conversion had employed a direct drive if the results might have been different.....but I am biased.

For Scotts info,here are some points to consider. A cast iron V6 with a reduction drive will weigh as much or more than many aluminum V8s. The V6 will either need a weaker 120 degree crankshaft or a balance shaft to run smoothly, and the power pulses will be larger. An aluminum V8 like a Rover or an LS engine with direct drive will be smoother, have smaller power pulses, and be comparable in weight. It might even be lighter. A Rover is about 300 lbs and an LS about 400 lbs. There is room to lighten both of them some. An aluminum GM V6 block was too expensive for most peoples taste at about $5k. Then you had to buy the alum heads. A Rover or LS can be purchased or built for less than the alum V6. This line of thinking is more for an individual planning a one off build.
Fast forward to 2019. Today there are advanced aluminum V6 engines available that might make viable conversion candidates. Since you are looking for a way to grow a business, let me suggest that someone who made and sold a reasonably priced direct drive that could simply bolt onto engines acquired by grass roots builders could probably do pretty well today. Most of the older companies went with belt driven redrives and as those engines became less current they gradually faded away. With todays new crop of V6s, if one produced 150 hp at 3000 rpms and a reasonable weight, there would be a market for them. All you have to do is design a simple bolt on drive at a reasonable cost. If its easy, people will give it a try. $25K for a redrive eliminates a lot of interest. $3-4K for a smooth problem free direct drive is a lot more marketable. You get more horsepower with a redrive.....but you get more weight,expense, and problems. A niche where someone can obtain reasonable power with a simple reasonably inexpensive bolt on direct drive might be a viable market.

I think many builders would live with the idea of an additional 100 lbs on the nose if they can get 200 reliable HP for $ 10-12K .
 
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pfarber

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Cost wise, once you hit $20k for a conversion (new or not) I don't think its an attractive offer. At this point, you're losing resale value. T-51s are just not mainstream nor are most 300+hp AC.

Maybe start a gofundme/kickstarter for a PSRU that has all the maths and CAD/CAM files, that would be a HUGE start.

But really, you can 'back of the napkin' design one and most likely have good results.
 

pfarber

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did you lose the prop? if so how did you survive?
More importantly, was there any significant amount of QA from the PSRU manufacturer?

I think Certified AC have it right w/r/t QA the important bits. When it comes time to by my PSRU its getting QA'd/NDT'd to rule out possible internal defects.
 

TXFlyGuy

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Titan's love affair with the LS3 is because it's an off the shelf crate engine, readily available, cheap, shipped direct from GM. Can't get a Honda V6 today like that, at least not the one Titan used.

And the SBC has a very good track record in aircraft.

Horsepower is not the real factor with the LS3, it is torque, and lots of it. The LS3 makes more torque at 2000 rpm than the Honda does at 5500 rpm.

The new HD PSRU is rated for 600+ HP.
 
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proppastie

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The new HD PSRU is rated for 600+ HP
really nice looking...do they talk about the testing?....interesting about the reverse threads for locking the shaft, much greater holding power, how many came loose before they changed it?
 

TXFlyGuy

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really nice looking...do they talk about the testing?....interesting about the reverse threads for locking the shaft, much greater holding power, how many came loose before they changed it?
Titan Aircraft will do all initial test flying (10-15 hours), using my plane as the test bed for the new gearbox / large prop combo.
 

TXFlyGuy

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A whole 15 hours for a development/test program?
It is well stated that most problems occur within the first 10 hours of test flight. Titan will do 15 hours, we will do the remaining 25 hours. And then ferry the Mustang back to Texas.

Note that these individual components have flown before, but not on Texas Toye.
 

wsimpso1

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Titan Aircraft will do all initial test flying (10-15 hours), using my plane as the test bed for the new gearbox / large prop combo.
I hope that you have sensing for oil level, oil temperature, and chips in it to give you some alert time if something does not run well.

Billski
 

wsimpso1

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Temp sensor installed.
That will go a long ways towards notice of any developing issues.

Do you have an oil level indicator? In the car business we found that temp sensors do not warn you when fluids are low, and will even lie to you about temps if the temp sensor is uncovered when fluid level is down. I like these - http://www.dwyer-inst.com/Product/Level/LevelSwitches/Optical/SeriesOLS - Wire it with a 2x22AWG shielded cable, hook it up to an input on the EFIS and set an alarm, and they run on 10-28 volts. Only drawback is the 1/2" NPT, and that is not awful. I am trying to figure out a place for one on a Lycoming...

Billski
 
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