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ej207 turbo engine in -4 or rocket?

T

the4ork

Member
I was thinking.... Tuners have gotten rather suprising #'s out of the WRX engines, I dont know what they weigh in at but I do know some ej motors have been used as I saw on sdsefi.com, but im unsure of which engines have been used, but would it be possible to pump out enough power to give a 540 a run for its money? Or at least match it in terms of performance?
 
yeah I did a search on it just a few minutes ago... Looks like more work, more wieght, less power, less reliable.... Sad.

But who's to sayyiu can't hop up a 360 or 540, they are around 8.5:1 compression factory right? Why not 10.5:1 or turbocharged with some custom forged pistons/rods and of course the manditory headwork that can be done, should u want more power....

I at least would like to do some headwork, friction coating on the internals and ceramic coated pistons, and heat dispersal coatings on the outside of the cyl's and heads all of which should hep keep the engine super efficient. I've done this to my vw turbodiesel engine with good results
 
Making more power than an IO-540 is childs play with even a 4 cylinder Subie, longevity at that hp level might be in question. Nothing like having some more cubic inches. A lightly turbocharged EG33 should provide power competitive with an IO-540 at low revs. I'm preparing just such an engine now for our RV10. The only internal mods are forged pistons- stock cams, rods, no head work. The rest of the engine appears very bulletproof- already has forged rods and forged nitrided crank from the factory plus massively thick castings.

Weight is very similar- long block is 250 lbs., Marcotte M-300 PSRU is 47, twin turbos with plumbing and intercoolers about 65, manifolds, injectors, TB etc. about 30, rad, scoop and coolant about 35.

I expect weight to be close to a wash using an MT prop.

The turbo might be cool in a Rocket at altitude with their higher limiting speeds but I don't think a Subie interests most of this crowd. If I were building a Rocket, I'd be seriously looking at an LS6- 380 lbs. for the long block and 405 hp stock. Only a bit heavier than the IO-540 but with easily 50 more hp at conservative rpms. Just over $5K brand new. I've got one on my shop floor right now...:cool::)

Alternately an LS7 is slightly lighter having titanium rods and intake valves, sodium cooled exhausts and 505hp for about $14K.
 
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Ross, IIRC, you are using a 6 cylinder in your 10.

4ork was asking about a WRX engine, which I believe is a 4 cylinder.

Or, am I just plane confused??

Seems to me that to get a WRX up to the same power as a 540, it would be extremely complicate in the management concerns, and I wonder at the reliability issues when pushed this hard.
 
The STI engine is a 4 cylinder 2.5L turbo and puts out 300hp stock. Theoretically you could derate this engine to 250 or so by reducing boost and peak rpm to under 4500 rpm and retain reasonable longevity. These engines have some pretty good factory bits like piston squirters and sodium cooled exhaust valves. The factory turbo would have to go and be replaced by a more suitable unit for aviation use. You'd end up with a very lightweight package which might be nice for a modified -4.

How long would it last running at say 180hp in cruise? Probably long enough to get your money's worth before overhaul.

Yes, I'm using the 3.3L six which will be just loafin' in cruise at 3500-4000 rpm and 30 inches or so.
 
Thanks Ross, re-reading my post, I noticed the link was to a 2004 model, glad it hasn't changed, I really look silly with egg on my face.

What is your 6 cylinder originally out of??? Only one I remember was from a 80s or 90s attempt at a sports car--------dont remember the name, 3 letters/initials IIRC, but sure had funny windows
 
I am flying with the STI engine in my RV7A and the more I fly it the more I like it. Eggenfellner only sold 25 of these in one batch and dropped them for the much simpler H6. I think this engine could be a really great RV engine if the package could have evolved a little more before Eggenfellner dropped it in favor of the H6.

Mine is supercharged rather than turbo and it works well.

It makes plently of power for an RV 4, 6, or 7, maybe a bit much for a 9. I am not sure about trying to compare a 150 cubic inch Subaru to a 540 cubic inch Lyc. Holy smokes, that leaves 390 cubic inches on the table. It is certainly capable of making a full 300 HP in stock form and as you can imagine, in the rally car racing they pump some amazing HP out of these things. Don't flame here, I am not saying this is appropriate for an airplane.

Run it up to 5400 RPMs, very close to 2700 prop, and close the waste gate and it really gets into the air in a hurry, like in set your hair on fire hurry. When I do this I see the MAP go from around 29" quickly up to 52". That is alot of boost but these engines are designed for it. They don't make alot of power without boost partially due to the rather low compression ratio. It also does very nicely to just run it up to about 2400 RPMs (prop, engine would be 2.02 X 2400 = 4848) and about 35" to 40" of boost. It still performs very respectfully at this setting, and the engine is basically taking it easy.

Part of the reason I was attracted to this engine was it's 300 HP,(in the car), rating but only using a portion of that in the plane. 75% of it's rated HP is 225. I will certainly not be cruising around using that much of this engine, so in theory it should last a long time and maybe be pretty reliable in doing so. Reliability of the engine is not such a big concern, gearboxes are:).

If it ever wears out I will just buy another one and bolt on the externals and go at it again. I have not checked the cost, but it has to be pretty attractive compared to some of the alternatives.

Burning auto fuel is certainly a plus these days.

As I get it more cleaned up I hope to get up with some Lyc powered RVs in my area and compare speeds and fuel burns etc. I will post results when it is time:)

I am having fun with my STI!

Randy C
 
Randy said:
Part of the reason I was attracted to this engine was it's 300 HP,(in the car), rating but only using a portion of that in the plane. 75% of it's rated HP is 225. I will certainly not be cruising around using that much of this engine, so in theory it should last a long time and maybe be pretty reliable in doing so. Reliability of the engine is not such a big concern, gearboxes are:).

Randy C
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Seems to me that if you were using 300 hp in your car, you would be writing this from jail, and your car would be in an impound lot somewhere. It probably takes only 45 or so horsepower to run your car at 75 mph, which is why modern car engines can usually run trouble-free for a couple hundred thousand miles. To be pulling 300 hp for take-offs and climbs, then cruising at 225 hp, the odds of long life don't seem so good.

On the other hand, Lycomings with directly driven propellers were built for this kind of stuff.
 
captainron said:
Seems to me that if you were using 300 hp in your car, you would be writing this from jail, and your car would be in an impound lot somewhere. It probably takes only 45 or so horsepower to run your car at 75 mph, which is why modern car engines can usually run trouble-free for a couple hundred thousand miles. To be pulling 300 hp for take-offs and climbs, then cruising at 225 hp, the odds of long life don't seem so good.

On the other hand, Lycomings with directly driven propellers were built for this kind of stuff.
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We've discussed this before. We're not talking about flogging the engine at 6500 rpm and full boost but rather derating it to about 4500 and about 45 inches. The WRC Subaru engines on which the STI is loosely based were pumping out nearly 420hp at 8500 rpm with good reliability. Stresses at the 250hp level and 4500rpm are a fraction of these levels. As previously stated, Fuji engineers have the right stuff in these engines for sustained high power levels. Yes, they are designed to do this if called upon to do it. Piston speeds and bearing surface speeds at 4500 rpm are only slightly higher than a typical Lycoming at 2700 rpm. All well within what is considered low stress for the parts used in a continuous application- about 3000 fpm.

It may surprise many lay people that auto engines today are designed and routinely tested to higher standards than certified aircraft engine requirements. The FAA only requires 100 hours of full throttle, full rpm for certified engines and another 50 hours at 75-100% power, 50 hours of which are required to be at redline oil and cylinder head temperatures. Most auto engine manufacturers today do a minimum validation of 200 hours of WOT at rated hp rpm and some as much as 1200 hours. In addition to this test, they perform cold weather testing to the tune of 1000+ cycles of cold soaking the engine to 0F and immediately taking the engine to WOT and high rpm until coolant reaches 240F. While the engine is still hot, 0F coolant is pumped into the engine until the block achieves 0F and the test is repeated- over 1000 times. Additional tests often include idle testing to 2000 hours with oil temperatures of 260F+ and transmission validation where the engine is cycled from low rpm to shift point rpm at WOT while the transmission is shifted up and down for up to 1600 hours. Not just one engine is put through these tests- dozens are. Wear rates are noted and obviously failures are not acceptable before release of the design.

The EJ series Subaru has proven itself capable in the real world of sustained high rpm/ WOT operation with the 1989 world speed record of 100,000 km by three Legacy RS turbos over 447 hours of 138.78 mph and an estimated 250,000 flight hours by over 1000 Subaru EJ powered aircraft including gyroplanes from RAF and Groen, fixed wing conversions such as those from Eggenfellner Aircraft and hundreds of other private conversion worldwide. One high time gyro operator in Australia reported 3800 hours on an EJ engine without overhaul!

You have to understand that liquid cooled engines are not affected from a materials/thermal standpoint like an air cooled engine. Head materials (aluminum) retain their T6 heat treatment in use unlike air cooled aircraft engines which basically operate in an annealed (weakened) condition.

Wear rates have a lot to do with how well oil films are maintained on touching parts. With closer dimensional and temperature control possible with liquid cooled engines and full synthetic oils such as Mobil 1, wear rates are very low. This is why 200,000 miles (average 8000 hours) in most modern car engines is no big deal today.

To answer the other question on the EG33, this engine was only used in the SVX sports car produced in the early to mid '90s.

I agree with Randy, the STI is probably the best basis for a Lycoming substitute- tough, light and relatively inexpensive.
 
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KISS

Lycoming is easier, quicker, proven and safe! Ask Vans! Experimental yes, practical, safe, easier, quicker and proven, IMHO nope. I would go on about one of the advertisers on Doug's site, but it would not stay posted here long.
 
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