I have one of those manifolds, too. Everyone should have one. Will give more HP, at the expense of low end torque, fuel consumption, make sure to have a tanker trailer. Great trucks, though. Usually have juice brakes.

Good opportunity for Cummins repower w/ a Brownie or 4500 or FSO.

Last edited by EdPruss; 01/12/2015 8:18 PM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.