I have had a 402 Chevy big block in my late 69 Camaro.Although i have owned the car for a long time i was wondering with my 4:11 gears,595 lift cam,28 inch tall tires maybe it is just not a great street car.I don't know about the gas mileage because I have never taken it far and has been in storage for a while.I was guessing my engine puts out between 425-450 Horse power.It is a durable motor.Forged pistons,crank,and rods.As much as I like it I want to enjoy it and I don't think it is a very streetable car that I can take very far without stopping for gas.I also use a 150 shot of nitrous and the motor can take ebery bit of it.I guess Im getting a little jealous of some of the LS1 engines making great power(getting descent gas mileage) even if it is not a big block.I know it would cost alot of money to swap an LS1 or LS2 in my car but maybe i would be driving it more and enjoying it.Has anyone done a swap like this or should i keep my current setup???