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rh77
03-13-2006, 11:50 PM
I know I speak for the minority here, but quite a bit of discussion relates to folks who have manual transmissions, and couldn't apply to those of us with slush-boxes. Just a rough guess, maybe 10% of members have the auto-trans.

Just an idea, but is there any interest for an automatics-only discussion area? As much as I'd like to be driving a manual, I'm stuck with what I have - and still looking to improve economy. If not, maybe this thread could be a place to talk about it.

Any thoughts.

RH77

PS - If anyone suggests a manual swap, a dope-slap awaits.

Matt Timion
03-14-2006, 12:10 AM
I know I speak for the minority here, but quite a bit of discussion relates to folks who have manual transmissions, and couldn't apply to those of us with slush-boxes. Just a rough guess, maybe 10% of members have the auto-trans.

Just an idea, but is there any interest for an automatics-only discussion area? As much as I'd like to be driving a manual, I'm stuck with what I have - and still looking to improve economy. If not, maybe this thread could be a place to talk about it.

Any thoughts.

RH77

PS - If anyone suggests a manual swap, a dope-slap awaits.

Great idea. I was considering adding a Diesel section, a micro-car section, and now an automatic section. One way I think this site will grow is if the forums become a little more specialized. Having a "General Fuel Economy Discussion" area is good, but if it's too general it will scare people away.

So give more ideas for more area specific forums and I'll get to it.

philmcneal
03-14-2006, 02:41 AM
yes automatic tranmissions have a mind of their own. Toyota's ECT, Honda's Grade Logic Control, GM 4 speed autos and many others have a mind of their own. I think an automatic forum is an excellent idea to expand the use of what they have.

Compaq888
03-14-2006, 08:54 AM
Good idea.

I believe the only good place where autos are good are for freeways. We are starting to get into the .5xx gearing for the last gear. Before it was high .6xx

Also since the CVT are going to appear on more cars it will be better for fuel economy and accelaration. Nissan is going to be putting CVT in all of their automatics and Toyota will be developing 7 and 8 speed automatics. I think this is great. With more speeds you can achieve better accelaration and better fuel economy. The downside of that is you'll lose more power because you got way more components that use up friction. The thing with CVT is that the technology is new and some manufacturers don't have it down yet.

SVOboy
03-14-2006, 10:31 AM
Hmm, automatic forum, I'll have to go and get my **** converted, I just looked at my new tranny last night, it's pretty, :)

krousdb
03-14-2006, 01:09 PM
Hmm, automatic forum, I'll have to go and get my **** converted, I just looked at my new tranny last night, it's pretty, :)

Not as pretty as the VX wheels i'll bet. Probably a lot heavier too! :)

SVOboy
03-14-2006, 01:24 PM
Not as pretty as the VX wheels i'll bet. Probably a lot heavier too! Smiling

I dunno, much more fun than the wheels at least. Indeed, it is heavier, but word on the street is that it's about 50 pounds less than the auto, and I believe it, :)

diamondlarry
03-14-2006, 03:13 PM
I think an auto section is a good idea also. Since I do own one vehicle that has one('92 Gran Prix) it could be helpful.

Sludgy
03-16-2006, 08:32 AM
There are lots of "chips" and "tuners" on the market to tune diesels. Most are for getting more power, which is something I don't want or need. Some also claim to tune the transmission shift points.

I'd like to tune my automatic tranny to go into top gear and lock the torque converter at about 1400 rpm. Anybody know of a chip or tuner than can change shift points without touching the engine calibrations?

rh77
03-16-2006, 08:50 AM
I remember seeing on one of those auto repair TV shows about a year ago where they re-tuned a gas Chevy Siverado after they put a new exhaust on it. They used this device that re-programmed a variety of things, including shift points. What is was, I can't recall, but I think when you buy the device it's a package deal with engine tuning and transmission programming. I'd have to do a search to verify if a transmission-only reprogrammer is out there for Fords.

I used to drive an E-350 Diesel for work (ambulance) which was right when the power-stroke came out, so we ended up with a bunch of the non-turbo dogs. I remember the TC engaging in 2nd gear, and then overdrive would kick in later-on. Man were they slow. Our local volunteer fire dept. bought a new E-550 with the power stroke (it was great to have the extra power), but I forget the shift points on the TC -- is it up around overdrive?

RH77

MetroMPG
12-15-2006, 04:43 PM
Here's an automatic driving tip someone reminded me of recently:

Most cars with a lockup torque converter lock up at a higher speed than you can typically cruise in the city.

But once locked up, you can typically bleed off speed (not coast - it may unlock again), significantly below the lockup point.

I've tried this in a Camry and my dad's Corolla. I think the Camry locks up around 75-80 km/h, but it'll hold the lock while cruising as low as the high 60 km/h range.

Something to consider anyway. Get it locked up, then bleed off speed and cruise slower. Might enable you to use lockup in lower-speed areas you normally think you couldn't.

omgwtfbyobbq
12-15-2006, 05:00 PM
I've also noticed that some tend to lock up at odd speeds. For instance, I can hit the cruise at ~55mph in the Camry and turn a shade over 2000rpm, bump it up to ~56mph and it drops to 2000rpm right on the dot. Pretty weird... But it locks up np when warm and cruising at 40mph/1500rpm, so no troubles there.

edit- Anyone know the efficiency difference in locked up versus normal operation?

LxMike
12-15-2006, 05:03 PM
Here's an automatic driving tip someone reminded me of recently:

Most cars with a lockup torque converter lock up at a higher speed than you can typically cruise in the city.

But once locked up, you can typically bleed off speed (not coast - it may unlock again), significantly below the lockup point.

I've tried this in my a Camry and Corolla. I think the Camry locks up around 75-80 km/h, but it'll hold the lock while cruising as low as the high 60 km/h range.

Something to consider anyway. Get it locked up, then bleed off speed and cruise slower. Might enable you to use lockup in lower-speed areas you normally think you couldn't.


i try to use this when possible. my TC locksup at 42 mph. I can bleed of speed and as long as stilll giving some gas it's ok, but let off gas and it unlocks and rpm's rise.

Silveredwings
12-15-2006, 05:14 PM
Well, the GS population may be something like 10% automatic but the real world (in N. America) is probably far greater than 50% automatic.

I personally don't want to own an auto. but I still think it's an important topic and I do read about automatics with interest.

psyshack
12-15-2006, 06:59 PM
Our Accord is a slush box. Being a I4 I think its a lot better slush box than whats in the V6 Blow Up Tranny Accords. I run M1 ATF in ours. I know its suppose to have Z1 in it. But it then shifts like a Chevy.

Anyway when I drive the Accord. I hypermile it about like the Civic MT.

Of note it locks into 5th at about 45 mph. Give or take 2 mph. Once locked you can bleed it down to 30 mph or so and keep it locked. This is very useful on level ground and way good on a slight down hill.

I high and low speed fas the car at will. The AT plays right along. i can top a hill at 50, to 75 mph, slip it in neutral, key off and key on and enjoy the no gas use down to any speed I choose. Fire the ICE and drop it into drive. Its all electronic controlled. Never so much as a bump or grind. The tach jumps up and relocks in 5th and off you go for the next fas. slow speed fas'ing is the same as high speed. Doesn't seem to bother it one bit.

I haven't been able to find a way to mess with its shift points much that amounts to anything.

I know I could do much better with a 5MT in the Accord. But its the wifes car. She can and will drive a MT. but she had to have a ^%$@%$%&*())@#@^% Automatic.

On the maint. side of things. I do the standard 3qt. tranny fluid dump and refill every 3rd oil change and also replace its little side stream tranny fluid filter.

Long live MT's!!!!!!!

psy

occupant
02-20-2007, 09:21 PM
I've owned a number of GM vehicles with the 2.5 liter engine and TH125C automatic transmission.

1988 Century
1992 Century
1986 Celebrity
1987 Celebrity
1989 Celebrity
1989 Ciera

The 1989 Oldsmobile Ciera seemed to have the highest speed before lockup would occur, typically around 40-42mph. The converter would unlock below 40 even if the throttle was not released. The Buick would lock around 37mph and unlock around 32. The Chevrolets from 86 and 87 would lock as low as 28 and release around 25. The 89 Chevrolet I have now won't lock until 35-36mph and releases as low as 25 but usually before dropping below 30. The 89 has issues, so maybe if it was running properly it would do better. The 89 ALSO will NOT go into lockup unless the SERVICE ENGINE SOON light is on. Driving on the highway can be amusing as the light goes on and off and the lockup kicks in and out. The car definitely has issues.

rh77
02-21-2007, 08:11 PM
My Pop's 1988 Olds RWD Cutlass has a terrible overdrive -- it kicks in and totally kills any momentum at cruise. At around 40-45 it kicks-in and drops the RPMs to where it can't continue at 45 without losing power and downshifting back and forth. At 55+ it works, but otherwise it almost dies on hills.

What's cool is the TC on the TSX. If I'm running in manu-matic 5th getting on the highway at 3000 RPM with about 60% throttle, despite going up a hill, it drops to 2200 RPM, takes-off and the FE climbs as the throttle is lifted.

Now the Integra is a different story. It has to be 100-degrees outside before the TC completely locks. It does a partial lockup at 20% throttle in the Winter (which is its most efficient position) -- but that's about 100 RPM -- useless!

Looking at the shop manual, more throttle locks it up tighter -- but it kills FE. Coolant temps are over stock, but the tranny fluid temp is probably marginal. Warm weather is MUCH NEEDED!!!

RH77

95_corolla
02-21-2007, 09:22 PM
what are you talking about locking up and bleeding speed I don't understand I drive an auto 1.8

rh77
02-21-2007, 10:43 PM
what are you talking about locking up and bleeding speed I don't understand I drive an auto 1.8

Simply put, most newer automatics have a "lock-up" style torque converter that allows the engine to spin at higher speeds without a direct connection to the wheels -- on a manual, when you let the clutch out, it directly locks-up the rotation from the engine to the wheels.

A torque converter has a clutch mechanism that uses fluid to either indirectly connect the engine and the wheels from when idling (so it doesn't stall-out), accelerating through gears at slower speeds, or once you reach certain conditions (like a higher speed, engine temp, and throttle input), the "TC" locks-up and makes a direct connection to let the engine do all the work. Why it doesn't work immediately would be hard on shifts and increase emissions.

It's often confused with "Overdrive" which is essentially another gear to shift into. The TC is more of a "sliding" engagement feeling. Once it locks-in, gentle pressure on the throttle can keep it locked for superior FE "bleeding". If you gas it too much, it unlocks for better acceleration, but higher engine RPMs and lower FE.

For a professional definition: Torque Converter. (http://en.wikipedia.org/wiki/Torque_converter)

RH77