The "practical answer" is that for what you pay to build a pump gas motor, the cost involved there will likely pay for years of the "extra fuel" that you currently use.

I didnt hear you mention you werent happy with your current performance, so save your money, pay the extra fuel bill.

Its unlikely(as you said it was a toy)that you drive it thousands of miles a year anyhow.

Even if the extra fuel is 300 dollars a year, thats probably 7-10 years worth of driving you will enjoy before your "project motor" ever sips one penny of pump gas.(three hundred a year i probabaly even a high end guess, probably lower)

Just something to think about.

I am kinda biased i guess, most guys that have what i consider to be high performance cars(like my 9 sec Duster)dont drive them a ton anyway.

I cant see spending all that money on a pump gas motor(unless it is the EXCEPTION, and is indeed driven thousands of miles each year)to sacrifice performance when a higher compression motor offers all the benefits EXCEPT cheap fuel.

gas around me here is 3 bucks a gallon for premium, and 5.29 for 110 race gas.

That 2 bucks a gallon difference is minute in the big scheme of things if you compare performance, and only drive maybe a couple of thousand miles a year.