.......Should I just upgrade to a V-8? Cause that seems like it'd be the easiest thing to do.
The first (5) years and 30K miles after the restoration my 68 Barracuda had the original \6 built with more compression, a Comp cam, offy intake, 390 4bbl Holley, 6 into 2 hooker headers and dual exhaust. This is what it looked like.
The car ran great, I had a carb heat kit that worked with the headers so cold weather was not an issue, never had a leak or clearance issue with the headers either. I got 19ish mpg around town and 22-23 on the hiway. The car would get a lot of interest at cruise nights when the hood was up (that gaggle of pipes is impressive), but would get a lot looks of disinterest when the hood was closed and they found out it was a 6.
Even with the engine mods (figured the engine was close 200 HP) the car was not fast. My wifes turbo PT Cruiser would walk right away from it. I considered doing a more radical build on the engine or adding a turbo which would get me to the power levels I wanted but it would still be a 6 cylinder which is not a muscle car motor.
I had been collecting parts for a v8 swap and had already upgraded the brakes, suspension, rear end and cooling system to handle the power so it was a simple matter of dropping in a v8 and connecting it up to the exisitng dual exahust. In 05 I built and installed the 360 you see in the picture below.
This engine was built with the intenet of making enough power to out run the majority of cars on the road and it does (very traction limited 13.7 @ 102 with miserable 2.2 sec 60' times). I have been tweaking on the tune and presently it gets 17ish mpg around town and 21-22 mpg on the hiway so I have basically not given up anything to the \6 in that respect. The only regret I have is that I didn't do it sooner, I have have put approx 40k miles on the 360 and have had a blast doing it.