Question for 170/6 Tuning

well,I use it from Mar/Apr to Oct/Nov as a daily driver , but I want a "little"
bit more performance and sound :D but it should still be at a relatively low
price at the gas station

ok so smaller the 4 barrel the better, I think a 390 would be perfect but they are hard to get...

compression bump, general cleanup on the ports and bowls. As you said 2.25 exhaust to the muffler, then 2.5 after to the bumper. it is all a good start but your also going to need to upgrade the ignition for a better bang.