What is STR when talking converters?
What is STR when talking converters? So I have been a manual transmission guy my entire life and finally made the plunge to an A4 Z28. I am trying to learn all about converters and auto's. When talking converters what is the STR stat that they always have like 2.2 or 2.6? What is the difference between a converter with a STR of 2.2 compared to a 2.6? thanks in advance for the info.
Also just to make sure I am correct, when talking Stall of a converter like 3200 thats basically the rpm that the converter can spin and still not let the car move right? So basically you can launch the car from 3200 rpm with a 3200 stall converter? If I am wrong please help clue me in. thanks
Also just to make sure I am correct, when talking Stall of a converter like 3200 thats basically the rpm that the converter can spin and still not let the car move right? So basically you can launch the car from 3200 rpm with a 3200 stall converter? If I am wrong please help clue me in. thanks
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The higher the STR the tighter it will feel. A 2.2 will be more loose than a 2.5. It all depends what your looking for. A 3500 with a 2.5 is great for the street. Vig converters will stall higher and feel more loose compared to the other brands.. For the second part of the question your right but there is alot more to it than that. It will effect your kickdown RPMS and your shift extension. Just as important as your launch, you 1st to 2nd shift wont drop down in the low 3000rpm range anymore. It takes out the dead spots and makes it more of a constant pull=making the car faster. It does however make it seem slower over time because your highs dont seem as high because you dont have any lows. It is more fun at times but at other times i wish had a 6 speed and i was slammin through the gears.
You say a 2.2 will be more loose compared to a 2.5. When would you ever want a looser converter? I would guess you always want a tighter converter, the only thing I can think that looser might be better for would be launching to keep wheel spin down. Is this why you would want a looser converter?
The only thing I could think of is if you want to have more effeciency on top end.
I have 2.5 STR on 3500 Yank converter. I can get a 1.8 60' on my 18" wheels/tires BFG KDWs slowly coming on the throttle after stalling it off the line.
STR has a small impact on how the converter feels driving around. Stall speed has a much bigger effect on looseness.
High STR increases torque multiplication off the line. If you have tires to handle it, a high STR will reduce your 60' time relative to a lower stall. If you have street tires, a lower STR can be easier to launch and may result in better 60' times.
A well designed high STR converter can be very efficent on the top end. It varies by converter model.
High STR increases torque multiplication off the line. If you have tires to handle it, a high STR will reduce your 60' time relative to a lower stall. If you have street tires, a lower STR can be easier to launch and may result in better 60' times.
A well designed high STR converter can be very efficent on the top end. It varies by converter model.
I don't have hard data to present here, but I swapped from a SS4000 2.6 STR converter to a PT4400 2.5 STR and it pulls much harder on the highway than the 4000 did. Kind of goes with what Ragtop said...it's a high stall with a high STR, but it pulls like an animal from any speed, especially up top where traction isn't so hard to come by.
It hits HARD off the line. With a high STR you better have some damn good tire to handle it. Lower STRs are easier to launch, but don't provide quite the good 60ft times high STR converters do.
It's been said that a 4000 2.1 STR converter can be easier to launch without spinning than a 3200 2.6 STR converter (per prominent people on the sight that have made such a switch)
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I went from a Vig 3800 2.5 str(I guess?) to a Yank ss4000 2.6 STR..Best 60' with the vig 1.66, best with Yank 1.59..both converters gave me 110mph..same tires, same everything..went from a 12.21 down to a 12.06..200 stall doesn't sound like much difference but it's that STR that hits like a **** out of the hole..
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Verdad Gallardo So what is a good Converter then for a 70% street 30% strip car that will have ET street's on it at the track? I want something daily driveable but will still be fun at the track. What do you guys suggest for a good converter to do this with?
. Depends on your setup. I started with a Yank ST3500 and moved up to an SS4000 and there was very little difference in daily driveability. All the noticeable gains were at WOT. Based on that, I'd say stick with a 3600-4000 converter. I currently run a Yank PT4400 on a daily driver and I'll never look back .
.The PT4400 is the pro thruster right? Its the last one on this page?
http://www.converter.cc/converters/street/GM/1/main.htm
