Author Topic: How to adjust your VNT Turbo  (Read 5245 times)


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How to adjust your VNT Turbo
« on: 23:09, Sun 21 September 2008 »
How to Adjust your VNT turbo,

Disclaimer - viewtopic.php?f=14&t=21

Please also refer to this DIY link also - viewtopic.php?f=14&t=6503

To adjust the way the boost comes in on a VNT turbo all you need to do is adjust the following:-

The grub screw on the side of the VNT (see attached picture)

Winding the grub screw in brings the boost in later up the RPM range and unscrewing the grub screw brings it in earlier.

Obviously when you mess with the grub screw you will need to adjust the pre-load on the actuator arm (this is the same principle as any normal actuator but doesn’t control boost it controls the flow of the VNT vanes thus creating more boost).  Be very careful with this as the longer the VNT actuator rod is the more the VNT will flow (More boost be careful as you could create over-boost problems if the vanes open to much).

Couple of links attached and some pics of my R5 with VNT


Whats is a VNT Turbo thread-