not, rich mixture for turbo's engine which can up boost.. for NA i said, i had try it man, i use perdana injector's for my 4g92 sohc engine n what happend is the engine respons is decrease... any engine with more air which lean mixture will get more power, u try burn petrol with less air n compare with more air it's totally big diff power u will get...
rich mixture can make ur engine overflow as well for carbie.. eg like 2 stroke engine, if too much petrol u give to the engine the spark can shut off coz of it's...
wanna prove, try it ur self... use bigger cc injectors..