Screw on back of TDi-Tuning Box?

**VXR CDTi** · 29th January 2008, 01:02

Any1 know what the screw is for on the back of a TDi-Tuning box? Will it increase or decrease the power by turning it? Is it likely to damage the box and engine?

**ianjofriel** · 29th January 2008, 01:06

if it's a pot, chances of ever getting it to the exact same again are slim

or does it have markings etc ?

have you tried the manufacturer of the box

**VXR CDTi** · 29th January 2008, 01:19

The manufacturer says they come as factory standard and the screw is set in the middle, didnt explain if turned it will add more or less power, neither did he say it is damaging, one thing i have noticed tho is that there is more smoke out the back end!

**diesel dog** · 29th January 2008, 01:45

Originally Posted by VXR Diesel (180bhp)

The manufacturer says they come as factory standard and the screw is set in the middle, didnt explain if turned it will add more or less power, neither did he say it is damaging, one thing i have noticed tho is that there is more smoke out the back end!

If it's the one I'm thinking of (black and white checked box) they are set at around 11 or 12 turns out of 23.But you are supposed to keep count because the screw is endless! If there's smoke turn it clockwise a turn at a time until there isn't.