Torque converter opinion needed
#16
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The restalled stock unit that Lexteme sells & the PI unit both have there places.
The Lexteme setup is nice for people on a budget.
The billit unit from PI is a really nice converter. They're more a hard core/race converter. You can get stall speeds on the PI unit that just wouldn't be possible with the lextreme unit. Say you have a fully built turbo car that doesn't see max torque until 4500 rpm, the PI unit can be made to stall up to 6,000 rpm. Since it's lighter smaller design it should have the effect of putting on a light weight fly wheel (but for a/t cars). It will take much more punishment than the lextreme unit. If it is like other PI units, it may also be a little noisy.
The Lexteme setup is nice for people on a budget.
The billit unit from PI is a really nice converter. They're more a hard core/race converter. You can get stall speeds on the PI unit that just wouldn't be possible with the lextreme unit. Say you have a fully built turbo car that doesn't see max torque until 4500 rpm, the PI unit can be made to stall up to 6,000 rpm. Since it's lighter smaller design it should have the effect of putting on a light weight fly wheel (but for a/t cars). It will take much more punishment than the lextreme unit. If it is like other PI units, it may also be a little noisy.
#17
I have a really quick question
I have installed the Lextreme TC on my car - I noticed that when I go from a complete stop, flooring my gas pedal, the tachometer needle still stops at 2100 - 2200 RPM for a second then start going up
Doesn't that mean that stall speed is still around 2200 RPM ? or a little less?
help please!
I have installed the Lextreme TC on my car - I noticed that when I go from a complete stop, flooring my gas pedal, the tachometer needle still stops at 2100 - 2200 RPM for a second then start going up
Doesn't that mean that stall speed is still around 2200 RPM ? or a little less?
help please!
#19
Lexus Test Driver
iTrader: (5)
I have a really quick question
I have installed the Lextreme TC on my car - I noticed that when I go from a complete stop, flooring my gas pedal, the tachometer needle still stops at 2100 - 2200 RPM for a second then start going up
Doesn't that mean that stall speed is still around 2200 RPM ? or a little less?
help please!
I have installed the Lextreme TC on my car - I noticed that when I go from a complete stop, flooring my gas pedal, the tachometer needle still stops at 2100 - 2200 RPM for a second then start going up
Doesn't that mean that stall speed is still around 2200 RPM ? or a little less?
help please!
I'm using the Lextreme TC with 2800 stall speed and in my opinion, it's really good. If I launch from dead stop, it won't shift to the 2nd gear until around 40mph. According to other discussions with other people who uses the PI TC, it's about the same, so I think this is usual for a modified high stall speed TC. It's my bad that I never paid attention to the Tach. But I believe it passes 3000 RPM easily at 40 mph.
It's more jerky than the stock one of course because it shifts at a higher RPM than stock. Therefore, the hp is transferred to the wheels quicker without the hic cup between the shifting. The peak hp stays the same because that's the max hp of the engine output. I don't feel that I lose any hp at the high end.
Last edited by stevechumo; 06-24-09 at 08:20 PM.
#20
Lexus Test Driver
#21
Thanks Steve! I will go ahead a check - I think mine was light blue and it doesn't shift until 40mph, but I thought the car should start moving full force when the tach. hits 2800 RPM, is that the case? or maybe I just understood the concept of stall speed wrong?
Thanks again
Thanks again
#22
Lexus Champion
iTrader: (-1)
It said it adds 40-50 hp.
Of course, the advantage to the PI torque converter is greater than just the stall speed. The smaller diameter and lighter weight decrease rotational mass and thus lower the rotational inertia of the vehicle, allowing for more responsive acceleration with the same engine output. Going to an ultralight wheel and tire combination would have a similar effect.
Thanks Steve! I will go ahead a check - I think mine was light blue and it doesn't shift until 40mph, but I thought the car should start moving full force when the tach. hits 2800 RPM, is that the case? or maybe I just understood the concept of stall speed wrong?
Thanks again
Thanks again
The torque converter is a fluid coupling of two discs that spin in accordance at rpm levels at or above the stall speed and in opposition at rpm levels below the stall speed. They spin in opposition to allow the motor to spin freely without engaging the drivetrain, preventing stall out at a stop. The spin in accordance to fully transfer power from the engine through the transmission and ultimately to the wheels when that power is needed.
If "moving full force" implies that the engine and transmission are spinning in harmony because the torque converter is "locked up," then you are correct in your grasp of the torque converter.
The issue with your shift point being high could be a result of confusion at the electronic level between the sensors that are relaying information and the computers that are processing that information.
There is a thread on this forum, started by O. L. T. if I recall correctly, that offers a suggested method to raise or lower the shift point by rotating a sensor that gives input to one of the computing units that governs the transmission. You might try to dig that up as a way to combat the problem in the meantime, until you find the desire to seek a more permanent solution.
#23
I took a video of my tachometer with the new stall TC (2700 2800 RPM)
http://www.youtube.com/watch?v=Qr6yQk5_YZE
Don't mind the CEL it is because my AFM is disconnected - Let me know if you think the TC is working as it should be - Thanks again guys!
http://www.youtube.com/watch?v=Qr6yQk5_YZE
Don't mind the CEL it is because my AFM is disconnected - Let me know if you think the TC is working as it should be - Thanks again guys!
#24
Steve this is exactly what I meant by "full force" - Just like when you release a clutch all the way up in a manual trans. car
So as you notice in my vid, the auto "clutch" is released at 2000 almost - You can actually hear the wheels skweek - I am starting to really think it is only a refurbished stock TC
So as you notice in my vid, the auto "clutch" is released at 2000 almost - You can actually hear the wheels skweek - I am starting to really think it is only a refurbished stock TC
#25
and here's another video of me having left foot on brake, and right one on gas pedal - note how the engine revs around 2100 RPM
http://www.youtube.com/watch?v=IovXTAcYWaw
opinion ?
http://www.youtube.com/watch?v=IovXTAcYWaw
opinion ?
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