put 493 in friends 71 duster-3400 lbs w/driver-eng has 98498 ross flat top pistons-approx 86 cc eddy heads,comp 650 roller cam,4.56 gears,14x32's-motor is zero deck-35 degrees timing-think maybe another .10 in combo-what do you think?thanks in advance for looking-rick

That sounds like pretty good numbers for that weight,depending on the other variables.Intake,carb,header size,etc.
Most flat top piston bigblocks I have tuned like 36-38 dgrees of timing,so you might play with timing.Carb tuning,playing with shift points,etc. might get you where you want to be.

What speed did it run??

60 ft was 139/140,1/8 mile 6.37/107,638/106,1/4 130/131-also w/better air today car ran 9.97 on brakes and also found timing was nor 35 but 30-timing lite quit so borrowed 2 lights and said it was at 30 degrees-did not change timing to 35 because no more time runs-won 1st round and 2nd round dialed 9.97 and ran dead on and lost due to light-may be another .1/.2 in combo though.

your post is hard to decipher...
but taking a little timming out will help get more mph..sometimes it translates into better et if the shift points hit the spot.
fwiw..

cheapst

looks pretty good to me.
1320/131= 10.07
Wondering about 1/8 mile number.
660/107= 6.16
May be room for improvement in 1st 1/8.
IMO