should i put in a 9/11?
- Thread starter spooldup
- Start date
A higher stall TC is probably a good idea on any SyTy. With a bigger turbo, it's almost a necessity. This really helps turbo spool up during transcient throttle slams. It helps the motor move into the power band much quicker.
The 9 / 11 torque converter is one of the most popular TC upgrades. This has a 9 inch converter with an 11 inch lock up clutch. This really locks hard compared to the stock TC. It's almost like having a 5 speed tranny.
Driving in stop and go traffic is a little different. Some describe it like driving with a rubber band. It takes more rpm to get things going, but when you drop the hammer, it's boom and your gone. There is also a drivability issue with TC lockup in ~40 mph cruise conditions, with a annoying vibration resonance. The best way around this is to drive in 3rd gear, until up to highway speeds. This works great for me.
Another issue with the 9/11 is that it will raise the motor rpm at the shift points. The tranny shifts based on mph - ~28 mph 1st to 2nd, 52 mph 2nd to 3rd, ~70 TC lock. With the loose TC, the motor will rev higher in each gear in order to get to the same shift points. In some cases, this will move the motor out of the peak power band on the high side.
Another plus for the looser TC is that it probably helps to protect the tranny some. With more slip between the motor and tranny, I'm sure the tranny clutches will last longer. I don't know if there is any real data on this point, however.
With all that said, I highly recommend the 9/11 TC. It really transforms the vehicle into one that is much more responsive in the street environment. Good luck.
Howard
The 9 / 11 torque converter is one of the most popular TC upgrades. This has a 9 inch converter with an 11 inch lock up clutch. This really locks hard compared to the stock TC. It's almost like having a 5 speed tranny.
Driving in stop and go traffic is a little different. Some describe it like driving with a rubber band. It takes more rpm to get things going, but when you drop the hammer, it's boom and your gone. There is also a drivability issue with TC lockup in ~40 mph cruise conditions, with a annoying vibration resonance. The best way around this is to drive in 3rd gear, until up to highway speeds. This works great for me.
Another issue with the 9/11 is that it will raise the motor rpm at the shift points. The tranny shifts based on mph - ~28 mph 1st to 2nd, 52 mph 2nd to 3rd, ~70 TC lock. With the loose TC, the motor will rev higher in each gear in order to get to the same shift points. In some cases, this will move the motor out of the peak power band on the high side.
Another plus for the looser TC is that it probably helps to protect the tranny some. With more slip between the motor and tranny, I'm sure the tranny clutches will last longer. I don't know if there is any real data on this point, however.
With all that said, I highly recommend the 9/11 TC. It really transforms the vehicle into one that is much more responsive in the street environment. Good luck.
Howard
Brian Hartman
New member
These 9/11's are killer in a stock application. If it doesn't, your tranny has issues or your truck is out of tune. After driving in a good stock truck with one, you'll wonder why they didn't come from the factory with a half way decent TC. The stock TC is a pile of junk just waiting to explode.