Auto Vs Manual

Auto Vs Manual Offroad

For those who don't know, I have recently upgraded to an SG auto forester, non turbo.

Last weekend was the first test of the auto and I am not sure if I am sold on the Auto or not. In some aspects it is great, it can crawl over bumpy terrain much more slowly than the manual which is what I wanted and they VTD locked up is true 4WD with no slipping detected so far.

However the auto gearing is VERY tall compared with a manual (12:1 vs the 25:1 I was running). I found I was able to reach stall on the torque converter very easily with no acceleration at very low speed and in reverse, torque converter stall without any wheels spinning at all. Where a manual SG with SF low range was able to accelerate at <50% throttle the auto could not at 100% throttle. When attempting larger dunes with a run up the highest RPM I saw was 3500 which occurred with the vehicle going quite quickly where as the manual could hit 6000rpm whenever it wanted. Maybe this could be fixed with a higher stall torque converter or a turbo (neither of which I am sure I want to do) but I am still a little concerned when in rough rocky stuff with the locker engaged trying to climb up a step I will hit stall and not be able to move... This videos show a comparison between the manual and auto. The auto is off the line at 100% throttle and the manual is feathering the throttle to avoid breaking traction.

https://youtu.be/ulePklS_r9g

Another comparison is on a wet road the auto SG can not break traction at all where as a manual SG can do 4 wheel burnouts in 1st high.

What mods have people done to improve autos offroad? Would be very interested to hear from anyone who has done a high stall torque converter.
 
get a better torque converter?
 
I think part of your problem may be throttle lag. I suspect that it's not just lag, you may not be actually getting WOT due to the DBW.
 
Rally said:
I think part of your problem may be throttle lag. I suspect that it's not just lag, you may not be actually getting WOT due to the DBW.
Click to expand...

I can brake stall on the torque converter which will remove any lag and the end result is pretty much the same. Possible the ECU is not giving full throttle but that would be a bit stupid of it. Who knows. I am new to this DBW stuff.
 
The ecu will do what it thinks it must to protect what it thinks needs protecting. And while there are products out there to improve throttle response on dbw cars, the whole issue of throttle lag is why I went to the considerable expense and effort of getting rid of dbw in my car.
 
I must not be very discriminating but I can't see all that much difference between the red car and the white one except that the white one gets more wheelspin. Which one is the auto?
I'm also a little ignorant on terms but I assume stall speed is when you left foot brake while stationary and put your foot down on the accelerator, the revs the engine stops increasing at is stall speed, correct? If so, my SH is 1500 rpm.
 
Beachworm said:
I must not be very discriminating but I can't see all that much difference between the red car and the white one except that the white one gets more wheelspin. Which one is the auto?
I'm also a little ignorant on terms but I assume stall speed is when you left foot brake while stationary and put your foot down on the accelerator, the revs the engine stops increasing at is stall speed, correct? If so, my SH is 1500 rpm.
Click to expand...

Yep thats exactly what stall is. On the SG is 2200 rpm.
White car is the auto. The difference is in the takeoff. White auto at 100% throttle is incapable of wheelspin where as the red at light throttle could still spin wheels. There was times during the day when climbing high traction surfaces that it would just crawl up at 100% throttle and be unable to accelerate. Where as the manual could accelerate (and dig holes if it wanted).
 
Interesting how post 12 in that link thought the 4eat was better then the 5mt for climbing when comparing like engines. That was the opposite of what was experienced by Dedman and I on the weekend! My manual seemed to have double the power of the 4eat despite being behind the same engine. Autos are know for robbing cars of power, but Subaru's auto seemed particularly bad. Pretty much came down to the auto being limited in rpm while manual could easily do what ever rpm I wanted and change rpm rapidly.


Would be interesting to know what others have done to get more engine rpm through the 4eat while at low speeds. Manuals can just change low range and diff ratios, but there seem to be less options for autos...
 
Red XS said:
Interesting how post 12 in that link thought the 4eat was better then the 5mt for climbing when comparing like engines. That was the opposite of what was experienced by Dedman and I on the weekend!
Click to expand...

Think you will find that is in the US where they do not have any dual range. 4EAT would likely be better than a single range manual in most situations.
 
I just checked and found that at 2200 rpm you should be getting over 90% of engine torque in a 2.5NA so the auto should be able to break traction if the manual can do it at lower revs unless as Rally says, the computer is saying no but that would amount to a form of traction control which may be a possibility if the snow button is in operation. That's if it has one. I'm not familiar with that model except that some club members were radio chatting about their snow buttons on a recent trip.
 
Beachworm said:
I just checked and found that at 2200 rpm you should be getting over 90% of engine torque in a 2.5NA.
Click to expand...
Really? 90% sounds high given max is at 4400rpm. Does have a hold button that makes it start in second and a power button which seems to do nothing. Was either in power or nothing mode at the time.
 
150 at 2200
162 at 4400
140 at 1000

It has a very flat torque curve I think this is in ft/lbs


How steep was the high traction surface?

There is a very steep street not far from me. I'll measure the slope and try a standing start locked in low to see how mine accelerates (its bitumen so I doubt I'll get more than a chirp from the front wheels)

Is it possible that the hold button is malfunctioning and its holding second to take off when you select first gear even if the button isn't depressed? It certainly sounds like it could be something like that.
 
I have driven an SG2 auto, only on road. The throttle lag was atrocious, and interestingly far worse than what is essentially the same setup as an 05 Liberty. Off the line it was extremely lazy. You can never be certain but to me it seemed that whatever I was demanding of the engine was being buffered by the ecu. I would suggest an electronic solution rather than a mechanical solution, or at least give it equal consideration. Dbw isn’t traction control. It’s a pain in the arse which has allowed manufacturers to quote higher power or torque figures to induce a sale but in most cases denying you access to it in order to reduce warranty claims. Not that an na Subaru h4 are has much power or torque anyway.
 
Unlike Rally, I have never driven an SG at all. The only experience I have is with my auto SH (NA) and a manual 98 Forester. I found the 98 to be totally gutless but I've been surprised by the SH. Off the line, it's a bit of a surprise. I had no trouble beating a manual BRZ over the first 60 feet. I have noticed that it tends to come on song in a very "cammy" way at about 3500 rpm at which point it seems to accelerate more strongly.
 
Beachworm said:
150 at 2200
162 at 4400
140 at 1000

It has a very flat torque curve I think this is in ft/lbs


How steep was the high traction surface?

There is a very steep street not far from me. I'll measure the slope and try a standing start locked in low to see how mine accelerates (its bitumen so I doubt I'll get more than a chirp from the front wheels)

Is it possible that the hold button is malfunctioning and its holding second to take off when you select first gear even if the button isn't depressed? It certainly sounds like it could be something like that.
Click to expand...

Interesting. If that is the case the perhaps the ECU is playing dodgy buggers =( Good to know that it has such low down torque. Makes me think a high stall torque converter isnt going to do as much as I thought. That is pretty crazy 1000rpm torque figure...
My old EJ20 supposedly produced less peak torque than the EJ25 at 1000rpm...

Not sure how steep it was, was just steep compacted sand where the car was moving forwards (just) rather than digging.

Hold button definitely works. You can tell when that is in use 100%.
 
Rally said:
I would suggest an electronic solution rather than a mechanical solution, or at least give it equal consideration. Dbw isn’t traction control. It’s a pain in the arse which has allowed manufacturers to quote higher power or torque figures to induce a sale but in most cases denying you access to it in order to reduce warranty claims. Not that an na Subaru h4 are has much power or torque anyway.
Click to expand...

Is there anyway to tell if the ECU/TCU is limiting power output? Do you get this sort of information from OBDII? Or is it a matter of sticking a snake cam into the intake to see what the butterfly is actually doing?
 
You must log in or register to reply here.
Back
Top