Tom,
The engine loves to rev. I can buzz this to 6200 RPM easy with the stock motor. The mid range is quite strong and it'll smoke'm easy with a bit of converter load. With a manual it would be crazy. The 1-2 shift burns the hides for 20', the 2-3 a good 3-4'
It runs out of 2nd gear at 75 mph....! I haven't found enough road to run out of 3rd....
I bet in a more aerodynamic body even your EC it would get 26-28 MPG. The '51 is a big brick... Bet in OEM stock form the truck would have a hard time going faster than 80 MPH.
The motor likes to turn 2600 to 2800 on the highway, just one problem this is 75 to 80 mph - way over the local limit. So I think 3.7 or 3.9 gears would be better than the 3.5's that i currently have. I suspect that it will get better mileage with more gear as at 2000 its not in its power band and you need to crack the throttle more. I tried this by running in drive at 2750 rpm - the motor needed just 47/256 on the VE table at 2750, shifting to 4th (OD) at 2000 it needed 130/256 VE which is a lot more fuel almost 3x as much. The trail blazers come with either 3.5, 3.7 or 4.10 gears. For folks not EFI friendly VE is the fuel control table. 256/256 is 95% duty cycle on the injectors.
The motor like to idle on just 7/256 - basically very little fuel .
M.
Last edited by efi-diy; 06/19/08 11:18 PM.
