does the 6.9 have a vacum regulator valve like the 7.3 for trans. shifting ? If so is it located on the IJ pump? how is it adjusted?
also i have an 86 f-250 will the 7.3 drop in in place of a 6.9 with auto tranny?

 

The 6.9 and the 7.3L are virtually the same, they will bolt right up, I own an 88 that had a 7.3 in it, i put in a 6.9L that i rebuilt. No problems. The vacuum actuator for the shift point is located on the Drivers side of the Injector Pump, little black dealy w two screws into the pump housing, has slots to move the actuator forward or reverse. Loosen off the screws, i believe that moving it forward will increase the max rpm to shift the trans at higher speed or rpm, and moving it back to the firewall will reduce the shift point to lower rpm, or speed, to drive around town, and not scare the crap out of everyone as you scream by at 3000rpm in 1st gear!! LOL

BigTex2 88F250, 6.9L, 4x4, Stinger kit, c6, 4.10's, lockers, the old girl just wont die, 850,000miles and still counting!!