Here's what I found...i don't have a manual, but this was posted on one of the boards i visited. Take it for what it is. Another option is to look at AERA's Prosis Software to see if the specs are listed. My copy is currently unavailable. Also look at Roy Berndt's article on rebuilding 6.9/7.3 (Engine Builder, July, 2006).
This Information came from a 7.3L TSB. Note that some of the torque specs were changed for head bolts when turbochargers were added to the
7.3 and the 6.9. These torque specs are generally 10
lbs over base figures. Also note that the comments regarding flywheel compatibility are contradictory with Ford p/n's for the 1987 version of the 6.9 that uses a 7.3 flywheel from the factory.
First year for the 6.9 - 1983
Last year for the 6.9 - 1987
By 1988 all production 7.3
6.9 - Max H.P. 175 Torque 318 ft. lb.
7.3 - Max H.P. 185 Torque 338 ft. lb.
6.9 max torque at 1800 RPM
7.3 max torque at 1600 RPM
Both max HP at 3300 RPM.
7.3 external identification variance from 6.9 - New fuel filter/fuel
heater/water separator, larger/taller cylinder head bolt bosses with
ribs. Dual mass flywheel on 5spd.
Crankcase differences
Cylinder bore - 6.9 = 4.00"
Cylinder bore - 7.3 = 4.11"
Stroke for both - 4.18"
Top deck thickness - 6.9 = .500"
Top deck thickness - 7.3 = .560"
Oil drain Back holes - 6.9 = 3/8"
Oil drain Back holes - 7.3 = 7/16"
Cylinder head changes
Cylinder head bolts - 6.9 = 7/16"-14 UNC 5.25" long
Cylinder head bolts - 7.3 = 1/2" - 13 UNC 6" long
Cylinder head bolt washer 6.9 = .105" thick
Cylinder head bolt washer 7.3 = .134" thick
Head bolt torque -
6.9 with new bolts = 75ft. lbs.
6.9 with used bolts = 85ft. lbs.
7.3 new or used = 100ft. lbs.
Cylinder head gasket changes -
Fire ring I.D. 6.9 = 4.14"
Fire ring I.D. 7.3 = 4.22"
Gasket cutouts elimitated between cylinders on the 7.3 to eliminate cosmetic corrosion phenomenon.
Viton oil drain back sealing rings added to the 7.3 (also used in later versions of the 6.9 head gasket, then eliminated again).
Head design changes -
6.9 features "centered" glow plugs, while 7.3 are "off-center"
Injection nozzles have been retracted on the 7.3 .060" to facilitate Federal and state emission certs.
Precombustion chamber volume -
6.9 = 18.34 cm3
7.3 = 20.42 cm3 (increased only for emissions certs)
Precombusion chamber inserts are physically interchangeable, however the
throat has been redesigned to distinguish them apart, and the 7.3
prechamber cub has an embossed "88" on it.
Valve Stem -
The 7.3 valve stem oil shield is larger to reduce hydrocarbon emissions. Intake and Exhaust shields have been color coded, even though they are identical and interchangeable.
Coolant passages -
The lower corner coolant passages on the cylinder head on the 7.3 have
been plugged. This change is introduced to eliminate lower corner
gasket coolant seepage during cold start engine warm-up. Mating
passages in the block are also plugged. (could be why we hear more 7.3
overheating issues).
Exhaust valves - The 7.3 exhaust valve has had its alloy composition
changed, with more nickel, chrome, and silver content, and decreased
manganese content. The 7.3 valves may be used in the 6.9, but not the
other way around.
Piston and ring sizes increased in accordance with bore changes. The
7.3 utilizes select fit pistons at the manufacturer. The engine is
produced with A,B,C and D size pistons and cylinder bores. When
re-using pistons, "A" pistons should go in "A" cylinders, and "B"
pistons in "B" cylinders and so on. These letters are stamped on the
pistons and the cylinder bores at the bottom of the bore when viewed
from the crankshaft side. Service part pistons can be utilized in any
bore, and are identified with an "S".
Flywheel -
IMPORTANT. DO NOT USE 6.9 flywheel or vibration damper on 7.3 or vice
versa. If components are intermixed, engine vibration and premature
component wear may be encountered. For identification, compare these
part numbers.
Vibration damper 6.9 1805414C1
Vibration damper 7.3 1809117C1
Flywheel Auto 6.9 1803219C1
Flywheel Auto 7.3 1809212C1
Flywheel manual 6.9 E7TA-6477-AB
Flywheel manual 7.3 E8TA-6477-AA
Injection Pump - Changes have been made to increase fuel flow and
change ignition timing on the 7.3. Low and High altitude calibrations
are available for both.
6.9 High - 1807568C91
6.9 Std. - 1807560C91
7.3 High - 1809045C91
7.3 Std. - 1809121C91
Injection lines - Due to the .060" retraction of the injector nozzle on
the 7.3, all 7.3 injector lines have been shortened by .060" However,
all lines with the exception of #1 on F series, and #4 on E series, are
interchangeable between 6.9 and 7.3.
Cylinder wall honing -
Plateau cylinder wall honing has been implemented on the 7.3 to promote ring seating and engine break-in.
Front Cover -
The 7.3 features an embossed front cover to improve sealing and eliminate water pump replacement due to gasket seepage.