Old days rules. Gasser, 10% engine set back, altered 25%, Measured from the center of the spindle to the first spark plug. Art
gasser - she farts when she walks by altered - she's a little cross-eyed but still cute enough to kiss
In a gasser engine set back is limited to 10% from stock In an altered it can be 25% Gasser must have fenders, an altered does have too. An altered is typically a race car built with a portion of the body of a car . Hopefully it isthe portion where the driver sits. Often there is not much else there. A Gasser is the complete car or looks so although often no bumbers. Don
Gassers have fenders, headlights, etc. = street legal Altereds no fenders plus the engine set backs listed above Red Dolmetsch beat me to it