These are Custom Velocity Stacks made to replace the restrictive factory velocity stacks. These are designed, tested on our Dyno, and manufactured all in house.
We have seen up to 8whp peak and over 10whp at 12,500 RPMs
**Dyno graph is stock stacks vs custom stacks and tuning**
**Velocity Stacks are made to order. We will contact you after purchase but they have a 2-3 business day lead time**