TB Types & Applications
S2
This TB works well on stock applications. The S3 does pull a little harder from a roll than
the S2.
S3
This is the tb you need if you have or will be modifing your car.
It pulls the hardest from a roll and works very well on A4 or M6 cars.

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Left - S2 TB / Right - Stock TB
S1
This is a low cost alternative to the S3.
There is no epoxy used to fill the air gap at the top of the tb.


Here's a dyno with a S1 tb.