Diablosport Forums

I have K&N intake and tuned my car for 91 octane gas. vehicle GT 08.
I want to add steeda underdrive pulleys
Do I need to tune it after adding the pulleys??

No you do not. That does not change airflow in or out, so no changes are necessary.

I read a couple of articles but still don't understand what these pulleys do....

black103 wrote:I read a couple of articles but still don't understand what these pulleys do....

In essence what they do is turn your accessories (water pump, p/s) slower which creates less drag on the engine and in turn allows yor car to accelerate more quickly.