[Bob Broberg SPF667 460BB]

That Roush 427ir is a hot small block and 9mpg seems low for any motor off the track. But, if it runs good, it's worth it. My old carbureted 460 even gets 17+ on the road with a 373 rear. The SPF tank should hold 17 gallons unless you have a fuel cell. With my last Race Demon 1000cfm carb I got 300 miles on a tank.
The Route 66 Fun Run standard route doesn't go 85 miles between fuel stops. Even the back way up through Yarnell is only 110 miles. Fun Trip. Been doing it since 2003. Join us. We can usually count on ending up with a dozen Cobras at the Red Roof Inn. Friday night out to dinner & Sat night picnic in parking lot or walk to Pizza Hut.
Standard Route: https://goo.gl/maps/TKWxNrdGMrYrjarh7
Back Way Route to Chino Valley: https://goo.gl/maps/Z473SArwPiDz97zBA
Here is the Fun Run start to finish on Sat to Kingman, Sun to Topock.
https://goo.gl/maps/G9YBCKLSB99fcog17

AZ Bob