driving automatics in manual gears

[solarsvx]

<<~~~~ scraches head""""

wow this is more information then i will ever need LOL..


so put it simple is it good to drive in manual or good to drive in drive?

whene i get peppy around town i will drive in maunual but on highways or curzing i wil have it in drive

[svxistentialist]

Originally posted by svx_commuter
This is all very interesting. Thanks Joe for the info and I would like to know a little more.....




So what does ATSG stand for?


John
(User of the SM)

Hi John and other SM users

ATSG stands for Automatic Transmission Service Group, they produce manuals for most common, and uncommon trannys.

See URL:

http://www.txchange.com/atsg.htm

Our tranny is listed as Subaru 4speed.

The manual is cheap, comprehensive, and in fact this should be listed as one of the LINKS on our main site resource page. You could do worse than buy one, from memory mine only cost about $17 or so.

Regards lockup during acceleration, I will switch on POWER mode and check for you. I do believe it will only work for gentle acceleration. If you ask for a heavy load, then the torque converter has to be brought in to multiply up and do the work.

I ran mine for quite some time in POWER mode. It was harder on fuel, 2-4 mpg. However, you might expect this as a trade off. What you got in return was willingness to change down quicker, and also holding on to lower gears longer. With the extra revs used, you had to expect heavier consumption. It was, however, much more fun.

It is my pet theory that this higher consumption was the reason Fuji discontinued the POWER switch on JDM cars about '94.

Joe

[svxistentialist]

John

I forgot to mention.

I gave the tranny shop all my info on trannys, the SM volume, the ATSG, the End Wrench overview, and pages from DRW, Level 10.

When I got them back, the ATSG was the one he apologised about the greasy fingerprints on.

That should tell you something!!

Joe

[immortal_suby]

Originally posted by svxistentialist


For the 2 or 3 range, lockup stated purpose is "Higher performance" As lockup will not operate due to certain conditions such as oil temp lower than 40degC, during gear shifts, when throttle fully closed or during rapid acceleration, effectively this means that in US or UK cars, lockup will never activate in the 2 or 3 range. This is because the Power mode is only caused to activate electronically during rapid acceleration.


Joe

Are we sure this is correct? I get a very linear relationship between engine and road speed accelerating in power mode through 2nd and 3rd gears, however, under normal acceleration in 2nd or 3rd the engine speed will hang around a certain rpm while the TC is slipping and the car is accelerating. This is with the selector in D. Is the wording in the manual causing confusion?

I have also noticed that I will get a quicker 2-3 shift in power mode at WOT than I do if I am backed off the throttle slightly. I mean that the shift itself will occur faster - not that the car goes faster. However, with the throttle backed off slightly the TC will slip during the gear change and with the increased rpm the car will feel as if it accelerates faster - it will 'jump' forward more powerfully as the shift completes. This happens in both svx's

I wish I had a light that lit up when the TC was locked so I could figure this out.

[svxistentialist]

Originally posted by immortal_suby


Are we sure this is correct? I get a very linear relationship between engine and road speed accelerating in power mode through 2nd and 3rd gears, however, under normal acceleration in 2nd or 3rd the engine speed will hang around a certain rpm while the TC is slipping and the car is accelerating. This is with the selector in D. Is the wording in the manual causing confusion?

I take it suby you mean that the linear relationship implies that you have lockup under power mode in these two gears while driving in D under power mode? This could well be so, and would agree with the manual definition of lockup under what they call "normal" control. My reason for saying it could not happen was the non-lockup condition they described as " rapid accelerator pedal depression" Most people do not see the POWER light come on without the use of hard acceleration, so I would see the two conditions as being mutually exclusive.

Joe

[svxistentialist]

Originally posted by immortal_suby



I have also noticed that I will get a quicker 2-3 shift in power mode at WOT than I do if I am backed off the throttle slightly. I mean that the shift itself will occur faster - not that the car goes faster. However, with the throttle backed off slightly the TC will slip during the gear change and with the increased rpm the car will feel as if it accelerates faster - it will 'jump' forward more powerfully as the shift completes. This happens in both svx's

I wish I had a light that lit up when the TC was locked so I could figure this out.

Yes, suby, these conditions appear to be catered for by the TCU and the lock-up control duty solenoid. I will quote the manual verbatim and let you draw your own conclusions.
<<
(1) Normal control:- Control content;
*Lock-up on/off characteristics are set for each range, gear position and pattern by throttle opening and vehicle speed.
*Fuel consumption, power performance and shift characteristics are taken into account.

(2) Smooth control:- Control content;
When switching from lock-up off to lock-up, the duty ratio{of the control duty solenoid} is first set to 25% and gradually changed to 95% for smooth lock-up operation.>>

If the solenoid is at 5%, the lock-up is off, and if at 95%, it is totally on.

Another paragraph about the Smooth operation explains further:-

<< DURING SMOOTH CONTROL

When the lock-up clutch is operated, the duty ratio of the lock-up control duty solenoid does not increase directly to 95%. Instead, it is first modulated to a pre-set value then smoothly changed to 95%. This operation allows lock-up duty pressure to be changed smoothly, achieving shockless engagement of the lock-up clutch.>>


Hope this sheds some light on it


Joe

[Andy]

This topic is really getting interesting, although a little over my head as I have only a very vague understanding of auto boxes and even less of torque converters. Is there anyone who can look into this deeper to give a definitive answer? It may also be useful if this info was collated somewhere for future reference.

[oab_au]

I can't see the torque converter locking up at any other time than when the car is cruising in Drive with warm oil.

When power mode is engaged, accelerating is the main objective. In this case the torque converter plays an important part in gearing down and increasing of torque to achieve the fastest acceleration.

The TC lock-up would be designed to be operating, to allow this car to cruse at high speed economically, to remove that last 5% slip when the converter is not needed.

Yes I think the book is confusing, in the way it is suppose to work. I am sure that my 95 mod only locks-up under the above conditions.
Harvey.