Some Subaru History Facts

Who cares, it's exotic.

[pavanbabut]

Originally Posted by ThetaReactor

Who cares, it's exotic.

yep.... same..... who cares!!!!??? i love it, thts it.

-Pavan.

Originally Posted by UberRoo

This "better balanced" or "lower center of gravity" stuff seems to be mostly rubbish. Just about every Subaru four vibrates just as much - and often more - than any Honda four. My old 1.8 motors shake like a Harley Davidson. Six is the minimum number of cylinders required to fully balance an engine without balance shafts. An inline six is about the smoothest running engine you'll ever find, except for inline eights.

The limiting factor on center of gravity seems to be the exhaust and oil pan, and Subaru seems to pay no special attention to keeping the engine low. Yes, the hood is lower because, as I mentioned, the advantage is that some configurations simply fit better. There's no reason an inline motor couldn't be turned on it's side for an equally low center of gravity. Saab tends to lean their motors over pretty far for a very low hood. (Lower than a Subaru.)

The disadvantages? Multiple heads is the biggest one. It means more parts, more weight, complexity, more exhaust plumbing, intake plumbing, larger valve train, twice as many cams, manufacturing complexities such as the wrist pin ports, and most importantly; higher production costs.

Our valve covers are rather inaccessible, they leak because of their orientation, changing spark plugs requires a hole in the frame rail. Pulling the crankshaft on any other motor doesn't require pulling the heads or removing the engine.

The engines, much like BMW motorcycles, are terribly wide, thus the reason they are always longitudinally mounted. That orientation requires a second set of bevel gears to change the driveline's rotational axis which means lower fuel economy and power transfer.

The only advantage seems to be their center of gravity, which in practice is never realized. (It would require a dry sump and radically bent exhaust headers.) Even this potential advantage is no greater than an inline motor. In fact, imagine if you turned a V8 on it's heads? The heads are heavy / the oil pan is not.

I think most of these examples are used in a situation where there could be improvement. No matter which way you slice it, the bulk of a boxer is going to be lower than any other type of engine. Some things that are wrong with subarus design are like you said, the huge oil pan, and exhaust headers, but lets not forget the intake manifold. Another problem is the orientation of the engine, all of the engine is in front of the front axle. That's not a good design when it comes to performance, nor is having all of the engine behind the rear axle like in porsches, bugs, ghias, etc. And boxers vibrate a hell of a lot! But vibration and inherit balance are two different things. Sure it's going from side to side, but who's to say this isn't a fault of the engine mounting? Group N mounts really get rid of most of this vibration in the engine area, and send it straight to the chassis. SVX valve covers are very frustrating, but not all boxers are. Go work on a 90-94 legacy. The svx is just not a very mechanically friendly car. To be honest I think boxers are the best piston style engine.

[benebob]

Originally Posted by paddlesnz

And that's because in the early '60s, Subaru Japan imported several boxer engines from Volkswagen in Germany for study and research.

Actually, I read somewhere that this actually happened in the 30's during the war build up years. Of course I don't remember where I read it but check out Subaru's Drive Magazine's old stuff on line. I'm 90% sure that's where I read it.

As for boxer engines not being balanced? I guess you never rode a Bimmer Bike? Balance and vibration are two seperate things. It is pefectly balanced which lends itself to being a very reliable cheap design for small companies to use. There is a reason why the EA-81 has been installed now in more "experimental" aircraft than any other engine. Reliability, good performance (yes I know it maxed out at 95hp in a US car with a turbo) but the internals can easily handle 150hp, no timing chain or gear and especially when mounted properly its balance!

[SVX-FF]

The main problem I have with inline motors over 4 cyclinders is the amount of power loss. If you stop and think about is you are lossing valuable power to weight. It is true that our boxer 6 has 4 cams instead of two and two cyclinder head instead of one, but if it was an inline 6 the cam would need to be a lot beefier to hold up to the torque. The forced on the metal over the length of a 2+ foot cam are greater than that of a 1 foot cam. This makes for a less effecient engine, that is why there are no more inline eights. The Lamborgini V-12 is only a 6.0L, not that long of a block. You add weight both with a long cams vers multi cams but the power gain of a multi cam could be greater. Let us not forget the intake here, the length of an inline over a boxer is twice as much. the longer the air has to travel the more it heats up, this is bad for compustion. I have no fact to back this up just a thoughts.

The Toyota Supra is a good example to use for this. The engine is an 3.0L inline 6 DOHC. The engine make about 320hp with twin turbos, not sur of the psi here. A Porsche 911 Carrera with a 3.6L boxer 6 SOHC air cooled makes 270hp only 50hp less and no turbos. SVX we all know that one. If the math is correct than the SVX with the 5 to 6 psi supercharger should have about 345hp. The Supra has to have massive counterweight on the crankshaft to offset the force of the pistons, the SVX does not. The boxer motor's pistons are each others counter weights.

I agree that the boxer style motor are the best in the piston category.

Steve

[UberRoo]

Porsche tends to crank out some really high compression ratios, thus the gads of power. Inline sixes and eights have mostly disappeared because they're too long. Because they started disappearing so long ago, most examples we have of them are the old cast iron blocks with carburetors and breaker-point ignition. Probably not the best comparison. The length of the camshafts and cranks really has little effect. The early problems with torsional vibrations is a thing of the past. Modern V-12s and even V-16s are stressed just as much, if not more than an inline six.

The way I see it, a boxer places the cylinders about as far apart as possible. If you bend that pancake into a 'V,' you bring them closer together, thus a shorter intake. An inline configuration is about as good as it gets, until you exceed four cylinders, then at six it's roughly a toss-up. Any more than that and the tables turn in favor of a multi-head arrangement, with a 'V' being optimal for a short intake or exhaust.

The inlet and exhaust lengths can be both good and bad. Personally, I prefer to keep them short, but having them long does offer certain advantages, (production costs and complexity not being one of them.) Long intake and exhaust runners offer outstanding torque and volumetric efficiency. Short plumbing offers throttle response, and peak horsepower; and also weight and cost savings.

To the best of my knowledge, most BMW motorcycles have balance shafts. Regardless, whether the pistons are directly opposed or directly in line, the opportunities to balance them are exactly the same. Yes, the pistons in a boxer move in opposite directions to give them balance, but they also move in opposite directions in an inline engine! In a 'V' motor, they're moving at odd angles, which has it's pros and cons. In effect, the angle of a 'V' motor can subdivide the vibrations making them into smaller vibrations.

There's absolutely no reason an inline motor could not be mounted on it's side. The only reason boxer motors are flat is because they must be mounted that way to make them fit. As I mentioned, Saab does this to some extent. Any way you slice it though, tipping a motor on it's side is an invitation to valve cover leaks. On any vertically oriented motor, the valve cover is just to keep dirt out. You can actually drive around without it. On a horizontally oriented motor, the valve cover has to keep the oil in, not to mention the seam down the center of the crankcase. Ever seen a VW Beetle that didn't leak? *chirp* *chirp* *chirp* Exactly... On any Subaru, getting to just about anything on the heads is less fun than on an inline motor. (For example, pulling the head on a Subaru requires pulling the motor. Not a problem on a Honda.)

I agree that the old EA-81s were fine engines. I also like gear-driven cams and pushrods. Of course, pushrods, chains, gears, belts, overhead cams, dual overhead cams, rotary valves, and so on - these can be had on any engine configuration. Exactly why Subaru motors are so popular on airplanes is not entirely clear to me. Perhaps it's because Volkswagen motors resembled Lycoming and Continental motors as an inexpensive alternative and eventually Subaru motors were adopted as the water-cooled equivalent simply as a matter of convention. (Funny, how once you reach 20+ liters V-12s and radials become the standard.) I've heard of people using other motor configurations in airplanes with success, but I can't fully explain the popularity of Subarus.

It seems to me that if boxers were such a good idea, everybody would be doing it. They do have some potential advantages, but the only one Subaru seems to be making use of is their marketability. Frankly, I wouldn't mind throwing a Chevy small block under the hood of my SVX, but I can appreciate how that would be sacrilegious. It'd be fast, yes, but permissible? I don't think so. I like my boxer, even if it's inferior.

“It’s a Subaru thing. You wouldn’t understand.”

[svxsubaru1]

Or else you could put the exhaust manifolds on top of the engine, and the intake below.

But you have to remeber that stright engines have long cranks that make the engines genraley pretty heavy for its size, when compared to a V or flat engine. like a 2jze (3 liters)is comparable in weight to chevey 350, (5.7 liters).

[Gravija]

i think a stock 2JZ-GTE is around 12-14PSi on stock turbos and they dyno around 280-300whp i think.
we have to see what LAN's supercharger will pull for us on the dyno.

thing is, peopel are making huge amounts of power out of that inline 6 (somewhere around 1000whp). I haven't seen a boxer 6 (namely an SVX one) that runs that high (tuned porsches probably do though)

Originally Posted by UberRoo

For example, pulling the head on a Subaru requires pulling the motor.

This is False

Originally Posted by Gravija

thing is, peopel are making huge amounts of power out of that inline 6 (somewhere around 1000whp). I haven't seen a boxer 6 (namely an SVX one) that runs that high (tuned porsches probably do though)

That's because there's no aftermarket for the SVX.

[SVX-FF]

Originally Posted by Gravija

thing is, peopel are making huge amounts of power out of that inline 6 (somewhere around 1000whp). I haven't seen a boxer 6 (namely an SVX one) that runs that high (tuned porsches probably do though)

That is if youhave an extra 13,000 to shell out for parts and replace everything in the moter. It is not a Toyota motor any more.Proof Linkie for cost of parts
I am sure for 13k i can get a boxer 6 up to that hp range if there was all the corrperate backing tha supra has.

Steve

[SVX-FF]

There are many auto makers that have or do slant there inline motors. Volvo has been doing that sence the first one I worked on was a '67. Doge had a slant 6. They are all tring to be like the boxer . Just kidding. There are advantages to almost every motor. There are many different types and veryations. Look at Chevy vers Pontiac. In 1978 the Chevy 350 made 150hp and the Pontiac 301 made 150hp too. what was the difference. Chevy was a 90deg v and Pontiac was a 60deg V. I had the Trans Am with the 301 Pontiac motor very nice but hell to find parts.

I think this it is great that there are so many different types of motors for us to debate over.

Steve

no you dont have to pull the motor to do heads on some subarus, have done many ea81s and ea82s,



here are a list of the motors as i know them

1000,
1100
1300
1400 ea63(quad exhost ports)
1400( dual exhost ports) very differnt motor head wise from above 1400
1600 ea71(both hydrolic lifter and push rod kinds)
1800 ea81 (both hydrolic lifter and push rod kinds)
1800 ea81T(turbo mpfi)
1800 ea82
1800 ea82t
2700 er27(ea82with 2 mor cylinders)
1800 ej22
2000 ej20
2500 ej25
3000 (???ez30)
3300 eg33

now subaru also made a 12 cylinder boxer for F1 racing but i dont have pix or anything with that aloth it was on the board before and also on ultimatesubaru.net

hope that helps with your quest,,,,,,

[NeedForSpeed]

The Pontiac 301 was not a 60 degree engine, and I don't believe GM has ever marketed a 60 degree V8. I believe Ford did, the SHO v8 designed by Yamaha.

Originally Posted by SVX-FF

There are many auto makers that have or do slant there inline motors. Volvo has been doing that sence the first one I worked on was a '67. Doge had a slant 6. They are all tring to be like the boxer . Just kidding. There are advantages to almost every motor. There are many different types and veryations. Look at Chevy vers Pontiac. In 1978 the Chevy 350 made 150hp and the Pontiac 301 made 150hp too. what was the difference. Chevy was a 90deg v and Pontiac was a 60deg V. I had the Trans Am with the 301 Pontiac motor very nice but hell to find parts.

I think this it is great that there are so many different types of motors for us to debate over.

Steve

[UberRoo]

Originally Posted by tailgatewagon

no you dont have to pull the motor to do heads on some subarus, have done many ea81s and ea82s,

Originally Posted by THAWA

This is False

I believe I stand corrected. I forgot that they use cap screws instead of studs. In lieu of that argument, it could be argued that they must compromise the use of studs for ease of repair. The Justy is, of course, an exception. (I wonder what they use?) In either case, a Volkswagen Beetle will still require removal because of the use of studs. I reckon that a Porsche is the same way, only those engines require more than a Toys'R'Us tool kit to remove.

Originally Posted by svxsubaru1

Or else you could put the exhaust manifolds on top of the engine, and the intake below.

It's been done. Perhaps not with a Subaru, but I've seen a Ford V8 and a Chrysler V8 with the exhaust coming out the top and an intake along each side. Kinda icky, but kinda cool.

Originally Posted by SVX-FF

I think this it is great that there are so many different types of motors for us to debate over.

Absolutely. An engine for every application. We haven't even mentioned the W-block, square-block, swashplate type, opposed piston, Deltic, or oddities such as the NR-750's eight valves per cylinder and two rods per piston. Plus there's Wankels, two-strokes, diesels, turbines, Sterlings, steam, and on and on. Somebody should start an engine zoo before Jay Leno gets the idea and hoards them all to himself.