ITB sizing - The crazy scheme continues to work very well. I'm now doing the background reading I should have done before jumping in with both feet. I found a good thread over on shoptalkforums by Paul, the guy who makes the throttle bodies at VW Speedshop. Although the thread is about IDAs, he states that individual throttle body butterflies on VW engines only have to be 42mm to exceed 200hp. I ball parked mine based on what I used on a supercharged Miata a while back, and bought 45mm ITBs. I doubt I'll be breaking 200 hp anytime soon, but I'll be ready. The downside is the throttle can be a little twitchy since you're opening/closing a lot of venturi space with small changes in the pedal. It isn't annoying or something I feel a need to change, but the thread recommends 34mm-36mm ITBs for most VW applications to get a more linear throttle response. Consider this as you are sizing the ITBs for your application. Here's the link: https://shoptalkforums.com/vie...e4d3024f76e3e18332c1
Mike