You are installing upgraded turbocharger / s which will increase the airflow to your engine. This increased airflow HAS to be accompanied by a properly working BOV system for the car.

We only suggest DV systems for cars running stock replacement turbos, with stock wheels, NOT billet wheels.  For anything else we suggest an aftermarket charge pipe coupled with a Turbosmart “RacePort” Bov, or Tial Q Bov. If you do not want the noise associated with a BOV you can purchase a Tial QR BOV, and recirculate the vented air

The PROPER spring HAS to be run in the these BOV’s for proper venting, and response. For the RacePort the “ORANGE” spring should be used for the Tial the “BLACK” spring should be used

This also needs to be coupled with a ¼” dedicated reference line the stock manifold reference line is too small, and is usually tee’d or shared, this will delay response, and cause surge when lifting. This is line is NOT adequate.

If you need help selecting the proper BOV system parts for your car, please email

Compressor surge, and the possible thrust damage due to an improperly or inadequate BOV set up is not covered under VTT warranty!