Anybody heard of this TAV gadget? Answer to TAV drag racing?

[TheDullCarbide]

Many people have had trouble getting the TAV2 with a 6 inch pulley to rev beyond top ratio when racing. What if you didn't need to reach top ratio?

https://www.gokartsupply.com/speedr.htm

 

[riverjohn]

So, set this limiter just short of full driver exspansion, keeping it just short of OD.
I'd like to try one to see the effect it might have.