I purchased from ACT Performance Products at the Griff Growl a smooth bore induction hose which fits between plenum chamber & air flow meter. This item replaces the existing spiral hose.
This upgrade is often touted as the best value for money performance enhancement for a Griff improving performance by approx 2-5BHP… not bad for £30.
I also purchased the ACT AFM to filter smooth bore induction hose to replace the OEM spiral induction hose. The new satin black hose offers an improvement over the original by flowing more air and being more resistant to heat.