Fuel Mileage booster’s
Yes, absolutely. Actually I did the math wrong it's more like 30% better.
1987 suzuki samurai, original hitachi "feedback" electronic carb that utilized an oxygen sensor. Best it did pre-turbo was 23-ish mpg. Installed turbo, 7 psi from a renault fuego (nothing special). Boost referenced fuel pump and installed a blow off valve. Immediately achieved 29-30 mpg. Plus it was much faster and made cool sounds.
I have pics if you really want I'll dig them out.
Even a supercharger, like on the 273, is supposed to increase mileage 1-3 mpg. Problem is keeping your foot out of it ;)