I have run with it on and off and without it in the system at all. It makes about a +1 MPH difference when on so I keep it , using it in high gear when fuel demand is critical. That's one good thing about drag racing , it tells you via the time slip if your modifications help or hurt.
Randy
I think that means your using 110% of your fuel delivery capacity without it, and I'm sure you know, that could prove to be one of the bad things about drag racing,.......when your told you hurt something!
And yeah, they're old technology, but they have proven do work reliably (if you have a good one) and if applied in a reasonable application and with a proper execution of installation they can provide that which may be required, and still impart the nostalgic presentation one might desire.
Scott.