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Can I run the crap out of my '05 OBW A.T.?


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'05 OBW (auto tranny) owner's manual says that fuel cut off won't let me rev the engine into danger. Can I just wind the pea wad out of it and not worry that I am damaging the engine?

 

If something did blow, would it be covered under warranty because the fuel cut off should have prevented failure?

 

What are your thoughts?

 

Ps. Owner's manual also says that engine-safe top speed in second is 64mph. That would be at the red line, I'm sure.

 

Juan

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In theory it's the warranty department that sticks a rev limiter because they don't want to have to pay out for a bunch of grenaded engines. You _could_ ding it off the limiter with some regularity if you took good care of the engine otherwise but I certainly wouldn't advise wringing it out like that as a habit. I'm not sure how the newer 2.5's are like but my 2.2 turbo feels like it doesn't actually do much above 5500rpm so running it harder to redline or fuel cut just burns more fuel and burns more transmission :)

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I have an 04 impreza wagon and that hasn't got any power above 5,000 rpm. I doesn't seem worth it to me but if your a real ********************* about it, I'm sure they would cover it. I mean it's a brand new car. I wouldn't do it with mine though.

 

-Chris

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I don't know exactly how the subaru auto tranny software is designed, but I thought it would automatically upshift at a certain RPM, which is determined by the throttle position and the transmission software. I would think that the software would be written to cause an upshift before the engine hit redline even at maximum throttle position, and will probably upshift at significantly lower RPM at a lower throttle position if it's written for decent fuel economy with a lighter foot. Can you select which shift points to use? I know on some you can select a performance shifting map with higher shift points or an economy shifting map.

 

Maybe I'm just making up BS, I hate auto trannies and have swore to never own another one. But that's my understanding of how the new computer controlled ones work.

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Thepower drops off steeply a few hundred rpm before the rev limit - so actually a lot of cars might have better -what?- 0-60 or 1/4mile whatever times shifting just before the redline anyway. If you were autocrossing and a section could ber run a little easier if you weren't forced to upshift then immediately downshift and decided to stay in the lower gear and bounce off the limiter - well, you're autox ing and if the shop finds out you're racing they may balk at covering warranty work - I dunno.

 

I doubt doing it occasionally is a HUGE issue - at the same time, I doubt doing it regularly is beneficial for 'racing' or necessary for performance.

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I don't know exactly how the subaru auto tranny software is designed, but I thought it would automatically upshift at a certain RPM, which is determined by the throttle position and the transmission software. I would think that the software would be written to cause an upshift before the engine hit redline even at maximum throttle position, and will probably upshift at significantly lower RPM at a lower throttle position if it's written for decent fuel economy with a lighter foot. Can you select which shift points to use? I know on some you can select a performance shifting map with higher shift points or an economy shifting map.

Maybe I'm just making up BS, I hate auto trannies and have swore to never own another one. But that's my understanding of how the new computer controlled ones work.

 

Automatics computer controlled or not will force an upshift no matter what the selector is in, it is done to protect the engine from the er um .. well .. not the most birghtest person behind the wheel.

The govener acts as a rev limiter on a manual tranny, and as a speed govenor on both. Subaru likes a one size fits all (hence why we can interchange alot of parts), so they done seperate the two.

Alot of cars have them now, why i dont know.

Once you get out of the power band,all the revs above that point are sort of useless in the upper gears. Some cars you get better performance (1/4 mile or zero to 100) at the very top end by staying in a lower gear

As far as you hating autos trannies, well thats personal, but some of the new ones are getting close to being hybrids, and almost last as long as manuals. Also the time diffenrce in performance is down to 1/2 second, and gas mileage is close to the same in both (or at lkeast within human error). Just an observation.

 

nipper

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As far as you hating autos trannies, well thats personal

nipper

 

Haha. It's mostly driving them in the mountains I don't like. To be fair, I've never actually driven an automatic subaru. Honda's and Ford (Explorer) mostly. It also annoyed me when I went to sell my Honda accord that no one here would buy an automatic.

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The automatic won't let you over-rev. Floor it from a stop and keep going, and the car will run to redline and shift. However, in many Subarus, it won't shift higher that the selected gear and bounce of the rev-limiter. Don't forget the redline is there for a reason- it's safe to rev the car that high. If the car has oil and is well maintained, wear isn't going to increase much.

 

And yes, the power does start to fall off before redline, but shifting early will start you off lower in the power band.

 

My 93 Legacy has 160k miles and it sees redline fairly often. What do they call that- an "italian tune-up?"

 

Why? because I like to be going freeway speeds when I hit the top of the ramp. And it's fun.

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the most important question hasn't been asked yet.....

 

why would you want to do this?

 

I want to do this because I'm getting tired of stepping into it to merge, pass etc. and having to watch the tach. I'd rather keep my eyes on the road and enjoy. With the new "throttle-by-wire" system, I can never tell how far I'm actually stepping into it; a spring is a spring and the response lag is intolerable. There simply is no feel for the throttle position relative to the pedal position -like when they were linked by an acutual cable. On my old Subie, '98, pedal resistance was valuable input and I never took the thing above 5,000 RPM and loved every rev.

 

I'm just looking for a comfortable/fun way to drive this thing. So far, it's simply a chore and no fun AT ALL.

 

Juan

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I want to do this because I'm getting tired of stepping into it to merge, pass etc. and having to watch the tach. I'd rather keep my eyes on the road and enjoy. With the new "throttle-by-wire" system, I can never tell how far I'm actually stepping into it; a spring is a spring and the response lag is intolerable. There simply is no feel for the throttle position relative to the pedal position -like when they were linked by an acutual cable. On my old Subie, '98, pedal resistance was valuable input and I never took the thing above 5,000 RPM and loved every rev.

 

I'm just looking for a comfortable/fun way to drive this thing. So far, it's simply a chore and no fun AT ALL.

 

Juan

 

its kinda fun too.....

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theres no throttle cable in the newer soobies? well, I'm never buying a newer soob than.. also I'm never going to buy an automatic either, it totally sucks driving in the mountains and off road

 

whats so bad about it, it has much faster throttle responses that u can actually feel(MY 04 accord V6 coupe)

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whats so bad about it, it has much faster throttle responses that u can actually feel(MY 04 accord V6 coupe)

 

but how much would it cost to replace one of those sensors/motors that control the gas?compared to cable.

 

i know.that's why there's warrantees,but what about when it's over

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but how much would it cost to replace one of those sensors/motors that control the gas?compared to cable.

 

i know.that's why there's warrantees,but what about when it's over

 

All it means is that yout throttle position sensor is now attached to the gas pedal instead of a cable and a spring to a tps and a butterfly valve.

i mean you can sit here and debate and say youll never buy it etc etc etc,,,, but then that means in about ten years you will be walking everywhere.

 

nipper

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