1800 RPMs

[jjmoore]

I have a 6.5 with 6.2 heads , a NA 6.5 IP with short injectors. I have 30x9.5 R15 tires . 342 gears , 700R4 trans, 1/2 ton SUB. I have detuned the IP 1/4 turn ccw as instructed. what MPH in OD is 1800 rpms. this is in a 1987 SUB.

[More Power]

About 65-mph.

A 1982 GMC K1500 pickup I owned that was setup nearly identical to yours (except I ran 31x10.50R15 tires) routinely produced 22-24-mpg at 65-mph.

Jim