Timing Question-'94 454 TBI

My 2500 454 (w/ 42k miles) is an absolute boat anchor. I believe the static compression is only 7.9 or 8 to 1. Stock timing is at 4 btdc.

I had previously installed a Gale Banks Power Pack and that made a measurable difference in performance. Where as before the motor flat ran out of steam at 3k rpm, it now keeps pulling nicely right up to redline. Along with that installation, Banks stated that you could bump the timing up to 6 BTDC. I ran it up to 8.

Still in all, I get horrible mileage, even on the highway, with lite throttle and if I hook my medium weight 20 ft boat to it, a vortec 350 will have no trouble keeping up with me in hilly terrain. (and get 50% better mileage at the same time)

I just recently bumped the timing again to 10 deg BTDC. It made a very noticeable difference on the low end (unloaded) and at cruising speed my foot is hardly depressed on the throttle. I'm sure that when I take another mileage check there will be a noticeable difference.

Any experience, out there, whether I can get away with bumping the timing another 2 degrees? At the current setting of 10 I get no pinging.

You are asking a lot from the computer to keep changing the timing that much. I would wonder if your cam has flattened out a bit. If you really want power stick a supercharger on it.