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what is an estimate of the stock hp and torque that the v6 makes with the automatic? dont need an exact. just wondering the what abouts that my car is pushing now
 

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MM's Resident Ricer
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I've always wondered why automatics produce so much less horsepower; is it because of the shift times or what?

Thanks,
Indybird
well the v6 manual and v6 auto (99-04) both make the same power and tq, but the auto makes less to the wheels because of drivetrain loss. the automatic transmission has extra stuff that takes more hp to run so it rob it from the engine and doesnt allow as much to reach the wheels as the manual.
 

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well the v6 manual and v6 auto (99-04) both make the same power and tq, but the auto makes less to the wheels because of drivetrain loss. the automatic transmission has extra stuff that takes more hp to run so it rob it from the engine and doesnt allow as much to reach the wheels as the manual.
Does the J-Mod do anything related to this? Even though I'm slowly learning about the engines on these cars, I've learned near to nothing about the drivetrain.

Thanks,
Indybird
 

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No, but will give you better shifts.
Is there such a thing as a more efficient Automatic transmission then?

Sorry to hijack the thread by the way, Bluestang, I figured you wouldn't mind seeing as your question was already answered.

-Indybird
 

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For our cars? Not really sure. But I remember seeing in a thread on here a while back saying that our autos were actually pretty efficient.
 

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Is there such a thing as a more efficient Automatic transmission then?

Sorry to hijack the thread by the way, Bluestang, I figured you wouldn't mind seeing as your question was already answered.

-Indybird
My 4r70w has a transgo manuel vb/shiftkit,b&m ratchet shifter,tranny cooler,and installing a 3300 stall converter in the next month. It's more efficent than a t-5 for what I'm doing with it.
 

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ya it really all depends on what you want. Like ^ said. Manuals will make more power to the wheels. But if you are doing drag racing and you have a good auto with a shift kit, stall converter you will run better times than a manual tranny cuz you wont have to release the gas to shift. It is just easier for drag racing. I am not bashing manuals, cuz i drive one and i like them, but when you get into the fast drag cars you need an auto to make shifts fast and get the best times possible.
 

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Is there such a thing as a more efficient Automatic transmission then?
Depends on how you define "automatic transmission". If you're talking something that uses a torque converter (my definition), then yes, the GM Turbo-350 and Turbo-400s use a little less power than the AOD/AODE/4R70. If you're talking a transmission that shifts itself with no necessary input from the driver, then very much yes, as there are auto-shifting transmissions that use a dual-clutch setup, thus eliminating the power-sapping fluid coupler. You can find such trannies in VWs (DSG), the Nissan GT-R, Porshes (PDK), and BMWs, as well as Ferraris and I'm sure Lambos at this point.

Also depends on how you define "efficient". I think of efficiency in terms of power to the input shaft verus power applied to the output shaft. With a torque converter, you get torque multiplication, and can actually get MORE torque out at low rpms (I don't get it either... I think it has to do with the input speed being higher than the output speed). I think this is part of the reason autos are so popular with drag racing. You can also look at the efficiency in terms of some set goal, such as a 1/4 mile time. With the quicker, more consistent shifts of an auto, you could certainly consider it more efficient than trying to hit that same speed/consistency with a clutch. But in terms of power in:power out, an auto consumes more energy, usual figures are like 10-15% power loss though a manual, 15-20% loss through an automatic.

Some of the lack of efficiency of an auto comes from the gear overlap that's inherent in the stock shifting (for "smoother" shifts). Put a shift kit in, and you're not losing as much power during shifts.
 

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ya it really all depends on what you want. Like ^ said. Manuals will make more power to the wheels. But if you are doing drag racing and you have a good auto with a shift kit, stall converter you will run better times than a manual tranny cuz you wont have to release the gas to shift. It is just easier for drag racing. I am not bashing manuals, cuz i drive one and i like them, but when you get into the fast drag cars you need an auto to make shifts fast and get the best times possible.
Depends on how you define "automatic transmission". If you're talking something that uses a torque converter (my definition), then yes, the GM Turbo-350 and Turbo-400s use a little less power than the AOD/AODE/4R70. If you're talking a transmission that shifts itself with no necessary input from the driver, then very much yes, as there are auto-shifting transmissions that use a dual-clutch setup, thus eliminating the power-sapping fluid coupler. You can find such trannies in VWs (DSG), the Nissan GT-R, Porshes (PDK), and BMWs, as well as Ferraris and I'm sure Lambos at this point.

Also depends on how you define "efficient". I think of efficiency in terms of power to the input shaft verus power applied to the output shaft. With a torque converter, you get torque multiplication, and can actually get MORE torque out at low rpms (I don't get it either... I think it has to do with the input speed being higher than the output speed). I think this is part of the reason autos are so popular with drag racing. You can also look at the efficiency in terms of some set goal, such as a 1/4 mile time. With the quicker, more consistent shifts of an auto, you could certainly consider it more efficient than trying to hit that same speed/consistency with a clutch. But in terms of power in:power out, an auto consumes more energy, usual figures are like 10-15% power loss though a manual, 15-20% loss through an automatic.

Some of the lack of efficiency of an auto comes from the gear overlap that's inherent in the stock shifting (for "smoother" shifts). Put a shift kit in, and you're not losing as much power during shifts.
Both of those posts answered my questions perfectly.

Thanks,
Indybird
 

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np. I would recommend keeping your auto, and just upgrading it with a shift kit and if your donig some drag racing a converter. I would also recommend a tuner that allows you to up the shift firmness giving rougher shifts decreasing the power loss of slipping into the gears.
 
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