robm

RE: Loyale heating up faster - could it be a smaller volume of coolant to heat up?

It could be the throw-out bearing. But to get to it, you have to separate the transmission from the engine, and at that point, it is about 90% of changing the clutch. The bearing is about $30, the whole clutch is about $300 or so, but the labour is just about the same, probably 4-6 hours, at a guess. This is a tough one. What price mental health?

I don't quite follow your thinking regarding the balance between rolling resistance and air drag. Nor would I describe the figures as "real world constants." They WERE real world RESULTS. One of the reason for the shift to FWD was a reduction in rolling resistance, so modern vehicles should be less than this. Subarus with AWD go against the trend. Modern cars are supposed to be lower drag. Certainly, the small cars I am thnking of were called econoboxes for a reason - they had the aerodynamic sophistication of a brick. However, I have noticed that new cars seem to have more frontal area, so I am not entirely sure the total aerodynamic package is that much better than it used to be. We gave up strong roof gutters and good ground clearance in the name of fuel efficiency, but may have lost that efficiency to increased head room. So these numbers are 2 decades or more out of date. But they still give a good feel for how much power is required to drive a vehicle, and how much goes to each component of total drag.

The R160 was standard equipment in the RWD Datsun 510. They weren't noted for failing with a stock engine, which was about as powerful as an EA82. Even hot-rodded ones didn't usually bother changing to a stronger diff. If you really want to put a v8 in front of it, get the R200. But why would you give up the good handling, reliability and fuel economy of the flat 4? And how would you get the 200 HP to the ground, with 60% or more of the car's weight on the front wheels?

My experience with "natural" water injection came on a Yamaha SR500 motorbike. 500 cc single, 9.0:1 compression, needed premium to run without serious knock. But I was an engineering student at the time, with a student's typical financial limits, and often tried to get by with the cheap stuff. There was a noticeable difference when it rained. Knock was reduced immensely. It even made a difference when running premium. That engine is so simple, but so sensitive, it is ideal for testing intake, exhaust, carburetion and other engine mods to see how they work. Too bad the ignition was not one of the easy things to play with! My experience with setting distributors came when the engine on that machine met an early demise and it was replaced with a Datsun 510. (No, I didn't squeeze the inline 4 into the motorbike frame, I parked the bike and drove the cage!) I found that 4 deg. more advance improved the fuel economy, but at the expense of knock. I found 2 deg. extra made for better mileage and slightly better power, with minimal knock. I have found the same 2 deg. extra advance to reduce the SPFI's fuel consumption.

I have never driven a viscous centre diff, but I much prefer the open diff to a locked one for driving on slippery roads. Locked diff for deep snow, and open diff for thin snow and ice. The locked diff on tight, slippery turns can make the car very tail happy. This won't help you at all in Australia! One objection to the viscous diff is they seem quite fragile. Tires of slightly different diameters, handbrake turns etc. are all supposed to kill the diff in short order. I never managed to damage the centre diff in my AWD Corolla, and it went thousands of km with different tires front and back and side to side, and handbrake turns on the icy street to line it up to turn into the driveway were the order of the day. If I could find a FT4WD with as few km as the rest of my wagon, I would think very seriously about installing it.

I bet the Subaru doesn't coast as well because of the AWD. More rolling resistance. Aerodynamics might come in to the picture, as well, although at less than 50 mph, this has less effect. Re: the difference between the two Saabs: Is the tire size the same? That might make a difference, if the new car has wider tires. Also, is the body style exactly the same, or could there be some aerodynamic differences, as well? The engine size/fuel economy relationship is not quite a simple as you make out. An engine that is under low load does not fill its cylinders completely. It only sucks in as much air as it needs to produce the power required. If the engine is very similar, same # and size bearings, pistons, cam drive system, etc., the extra drag from larger diameter rings that cover a slightly longer stroke shouldn't be that much greater, should it? My gut instinct says there is something else going on here. But my guts have been wrong before!

The SPFI long block has more compression, so the stock advance may be too much. There are other factor involved as well, so... Start with the recommended advance (8 deg. BTDC? Just hearsay, it probably says on a sticker under the hood.) Take it out and drive it. Try sudden full throttle in third or 4th from about 2000 RPM and listen for a rattly sound, like a bunch of dimes in a tin can. That is ping. If it does this, retard the timing a bit, say to 6 deg. BTDC, and try again. A short little rattle is not a big deal, but if it rattles hard and as long as your foot is in it, it is too much! Try it up long hills, too. And keep an ear out for it as the weather changes. Moist air can act as natural water injection, which reduces ping.

About 20 years go, Car and Driver's road tests used to contain figures that showed the horsepower required to drive the vehicle at 50 mph. They were even able to break that down into how much HP was used to overcome rolling resistance, and how much to overcome air resistance. The typical figures for a small econobox (Corolla, Datsun whatever10, Subaru of the day) was 15 HP at 50 MPH, 7.5 HP for rolling resistance and 7.5 HP for air resistance. These numbers would give good starting points for the physicists in the crowd to do their calculations, then they could go out and drop the cannonballs, and find out how closely the calculated results match reality. I suspect these numbers would apply better to the EA82 body style, as they are closer to the type of car that was being tested than a current EJ in shape, tire size, and curb weight. But it is still a reasonable place to start.

Sorry, Mike, it is not as simple as that. Vacuum advance is there to increase timing for part-throttle cruise conditions. This is when engine vacuum is highest, and the throttle plate open so the distributor can see it. At full throttle, there is little vacuum, and therefore not much vacuum advance. Remember, racing distributors didn't have vacuum advance, as they don't spend much time at part throttle (wIth any luck!) and don't care about fuel consumption. The idea of adjusting the cam timing by adjusting it by a tooth is not the best. The cam belt teeth are pretty coarse, one tooth is way too much. Anyone who has slipped a tooth when installing the cam belts can attest to the fact that they don't work too well in this state. I like the SPFI distributor, the best of both worlds, as the basic timing is set by distributor position, so it can be advanced or retarded by several degrees. More modern systems that take the timing off the crank leave the home mechanic no way to fine-tune the timing at all. I find 23 degrees advance improves fuel consumption, with absolutely no noticeable ping. I should try advancing it a bit more, just to see what the limits are

When it gets to the point where it is either a new bearing or a louder stereo- change the bearing. I have never had one get to the point where the "average" shop would have noticed a problem, as the usual means of diagnosing a bad bearing is to shake the wheel, and replace if it is sloppy. I would be scared to run a car under those conditions, but it seems to happen.

Maybe resetting the ECU would help?

You are probably not sucking in liquid water. In high humidity conditions, the water in the air condenses out as it goes through the carb venturi. The temperature drop can be large enough to actually cause ice to form. This is "carb icing". Putting warm air into the intake is the best solution. Making sure the carb has proper heating will help, too. This is one reason why carbs/manifolds have heating, and the main reason why they have hot air pipes to the intake. I can see you have the temperature control on the intake horn, but I don't see the hose to pick up hot air from around the hot exhaust manifold. Normally, this device mixes hot and cold air to get a constant temperature. They do get worn out, though. Some cars won't run well if this thing is fazooed.

Just to play the devils's advocate here.... Coasting in gear uses less gas, as the SPFI turns it off completely. BUT the car goes further coasting in neutral. SO, is it cheaper to coast a long way in neutral, idling at 1200+ rpm, OR coast a short way in neutral, and keep your foot on the gas for the extra distance it would have gone in neutral? I suspect this is not an easy question to answer. There are lots of variables (like how far can you coast, and how far do you coast) and no easy way to measure the outcome. Driving around town is so wasteful anyway, any difference could easily get lost in the noise. Acceleration is what burns gas, cruising at any speed below 100 km/h uses very little, idling uses very little, and decelerating in gear uses none. The difference between cruise, idle and decelerating is hard to measure against the cost of acceleration. GD, you say you know the pinouts on the SPFI in your sleep. Do you happen to know which of the test sensors has the VSS output available on it? And do you happen to know what the signal looks like? It should be possible to rig up an instantaneous fuel consumption measurement, using this signal and the PWM signal to the fuel injector. With this measurement and a stopwatch or other more accurate instrumentation, it may be possible to answer this question.

To get back to Daeron's problem: It sounds like you proved that it runs fine in open loop. So that means MAF or O2 sensor, or both. I am not absolutely sure it does ignore the MAF when running open loop, but a funky MAF will run better with more air flow. So, yes, I think your idea of combination MAF/O2 sounds about right. Good luck finding it.

Have you cleaned the MAF? It sounds like you aren't getting an accurate signal from it at cruise/low flow. At WOT it either goes open loop (MAF doesn't matter) or the high air flow gives a good signal. Cheap and worth a try. Shoot, I see now you did just clean it. Still worth a look, maybe it got gunked up again.

Back home again. I checked the AC output of the new alternator with a decent Fluke DMM. Essentially zero VAC at the battery terminals. So even if the little analog meter I used to measure the output of the old alternator was seeing DC as well, there was a good 15 VAC on the output. A good way to test for bad diodes.

The steering column has a true tilt as well, underneath.

Sounds like a carb model. Could it be carburettor icing? Check the air inlet temperature control system, if it has a carb.

Probably a 1990 turbo. I believe that was the last year the turbo EA-82 was built - for this market, at least.

155 is a bit skinny for a Subaru. The load rating is a bit low. 165/80 is the best I have found, and strange coincindence, it is exactly what came on the car from the factory!

Try the wrecker. There are probably little rubber hose bits that connect hard plastic pipes. The hose bits can be replaced with standard vacuum hose. Or you could just run vacuum hose all the way, with tiewraps to keep it out of the way. Good luck.

Is the vehicle in question FWD or 4WD? Could make all the difference. I have never looked at a FWD, but the 4WD is a lot simpler than semyonlibman describes. The 4WD has no cap, a cotter pin instead of a lock washer, and the bearings are all behind the hub, and don't come out with it. Unless they changed from '91 to '92 to '93, you don't have an adjusting screw. Yours are self-adjusting, with a little ratcheting quadrant thing that tightens up when the brakes are applied. Works great, as far as self-adjusting goes. Unless, again, this is a 4WD feature? I have never tried/had to loosen it off to remove the drum on mine. Lucky, so far. 91Loyale has the procedure to try. Good luck.

We are assuming that you are removing the hub nut, right? The big 36 mm one in the middle. The drum won't come off unless this is removed first. Subarus don't have the tapped holes, as the drum is the hub, not an extra piece of cast iron that slips onto it. Once the hub nut is removed, all that stops it from coming off is the shoes. There might be a build up of rust at the edge that stops the hub from sliding off. A little banging and wiggling should get it. Scrape off the rust before reassembly, to make it easier next time.

Maybe some sandpaper to get rid of the corrosion?