Speed Inc Tuned, 346, H/C/I, A4, 485RWHP 407RWTQ *edit* VIDEO!!!
05-10-2010, 02:51 PM
#184
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Really? 2.5str for the 4400 vs 2.6str for the ss400....how big of a difference in the 60ft do you think that'd be? Plus isn't the shift extention much better in the pt4400...seems like you'd lose almost nothing in the 60ft and gain a lot more on your two shifts. Just my opinion though as that may have been the one you just tried...lol.
05-10-2010, 06:06 PM
#185
There is no loss down low with the ss4000 over the pt4400, maybe a hundreth or two tops.We have run both.The Pt just gives up a little more than we like on the top end,660-1320,ET and MPH.Now if we were racing 1/8 mile PT all the way.The verter Chris tried was pretty much right in the middle of the two.
05-10-2010, 08:49 PM
#186
Really? 2.5str for the 4400 vs 2.6str for the ss400....how big of a difference in the 60ft do you think that'd be? Plus isn't the shift extention much better in the pt4400...seems like you'd lose almost nothing in the 60ft and gain a lot more on your two shifts. Just my opinion though as that may have been the one you just tried...lol.
thanks.
05-10-2010, 09:02 PM
#187
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From Yanks website:
Stall Torque Ratio is one of the most misunderstood aspects of torque converter construction. Our competitors often call stall torque ratio: torque multiplier. The stall torque ratio is the amount of engine torque that the torque converter can multiply at a particular rpm level. By definition, stall torque ratio is when the turbine is at 0 RPMs and the converter is at maximum designed stall. This will produce a positive push on the turbine to increase the torque to the input shaft of the transmission, multiplied by the designed stall torque ratio of the torque converter. For example, a stall torque ratio of 2.0 would multiply 200 lb. ft. of engine torque to 400 lb. ft. of torque at the transmission input-shaft.
The misconception of stall torque ratio is that more must be better. This is not always the case. High stall torque ratio applications, typically are for industrial equipment or engines with limited low rpm engine torque. With high stall toque ratio converters, there are important trade-offs. What you take at one end you give up on the other. Typically, a torque converter with a very high stall torque ratio, such as 2.0-2.5, will be much less efficient above its rated stall speed. There is a sacrifice in higher rpm efficiency to achieve high stall torque ratios. That lower efficiency translates into less horsepower transmitted to the tires over an RPM range.
The problem with a high stall torque ratio converter is that it is only high while the car is not moving. Maximum stall torque ratio occurs at wide open throttle with no rotation of the transmission input shaft. As the input shaft starts to rotate with vehicle forward movement, the stall torque ratio will become non-existent much sooner than a converter of the same stall, with a lower stall torque ratio. A converter with a stall torque ratio of 2.2 for example, would display that at the starting line, but it would drop off much sooner than a converter with a lower stall torque ratio.
For example: A competitor's converter with a claimed stall torque ratio of 2.5 (red graph line) would typically have an efficiency of around 90% at high RPMs (5,000 plus). That means 300 flywheel horsepower would translate to 270 horsepower at the transmission input-shaft. A Super Yank Converter with a stall torque ratio of 1.6 (green graph line) has efficiency in the 97% range. That means a 300 horsepower engine would transmit 291 horsepower to the transmission input-shaft: A gain of 21 horsepower! For an LS-1 customer dyno sheet showing 97% efficiency press here.
As you can see, the converter with the lower stall torque ratio will multiply torque for a longer period of time than the converter with a higher stall torque ratio. As most of you know, most racing occurs above 3,000 RPMs. That's why the lower stall torque ratio often wins the race:
*Lower stall torque ratio is gentler on the tires at the initial launch, but it will pull harder for the remaining 1,305 ft. of the 1/4 mile. Less races will be lost at the starting line from excessive wheelspin. Lower stall torque ratio will be more efficient and transmit more torque and horsepower to the tires. This translates into lower ETs and higher trap speeds!
Stall Torque Ratio is one of the most misunderstood aspects of torque converter construction. Our competitors often call stall torque ratio: torque multiplier. The stall torque ratio is the amount of engine torque that the torque converter can multiply at a particular rpm level. By definition, stall torque ratio is when the turbine is at 0 RPMs and the converter is at maximum designed stall. This will produce a positive push on the turbine to increase the torque to the input shaft of the transmission, multiplied by the designed stall torque ratio of the torque converter. For example, a stall torque ratio of 2.0 would multiply 200 lb. ft. of engine torque to 400 lb. ft. of torque at the transmission input-shaft.
The misconception of stall torque ratio is that more must be better. This is not always the case. High stall torque ratio applications, typically are for industrial equipment or engines with limited low rpm engine torque. With high stall toque ratio converters, there are important trade-offs. What you take at one end you give up on the other. Typically, a torque converter with a very high stall torque ratio, such as 2.0-2.5, will be much less efficient above its rated stall speed. There is a sacrifice in higher rpm efficiency to achieve high stall torque ratios. That lower efficiency translates into less horsepower transmitted to the tires over an RPM range.
The problem with a high stall torque ratio converter is that it is only high while the car is not moving. Maximum stall torque ratio occurs at wide open throttle with no rotation of the transmission input shaft. As the input shaft starts to rotate with vehicle forward movement, the stall torque ratio will become non-existent much sooner than a converter of the same stall, with a lower stall torque ratio. A converter with a stall torque ratio of 2.2 for example, would display that at the starting line, but it would drop off much sooner than a converter with a lower stall torque ratio.
For example: A competitor's converter with a claimed stall torque ratio of 2.5 (red graph line) would typically have an efficiency of around 90% at high RPMs (5,000 plus). That means 300 flywheel horsepower would translate to 270 horsepower at the transmission input-shaft. A Super Yank Converter with a stall torque ratio of 1.6 (green graph line) has efficiency in the 97% range. That means a 300 horsepower engine would transmit 291 horsepower to the transmission input-shaft: A gain of 21 horsepower! For an LS-1 customer dyno sheet showing 97% efficiency press here.
As you can see, the converter with the lower stall torque ratio will multiply torque for a longer period of time than the converter with a higher stall torque ratio. As most of you know, most racing occurs above 3,000 RPMs. That's why the lower stall torque ratio often wins the race:
*Lower stall torque ratio is gentler on the tires at the initial launch, but it will pull harder for the remaining 1,305 ft. of the 1/4 mile. Less races will be lost at the starting line from excessive wheelspin. Lower stall torque ratio will be more efficient and transmit more torque and horsepower to the tires. This translates into lower ETs and higher trap speeds!
06-06-2010, 05:35 PM
#192
hey bud shoot me a pm so we can added some mph to that car... 
we will figure something out, I have a weakness for ram setups...
also great times for that raceweight we would be heads up if you dropped 700lbs...thanks for the props
looks like we are close too I live in Plainfield/Romeoville
we will figure something out, I have a weakness for ram setups...
also great times for that raceweight we would be heads up if you dropped 700lbs...thanks for the props
looks like we are close too I live in Plainfield/Romeoville
Last edited by chrs1313; 06-06-2010 at 05:44 PM.
