We have found it to have boss 351 rotating assembly but other wise intake carb and headers it is a stock 1972 cobra jet
I dove the Cleveland that is now in my Maverick for 4 years while it was in my 1972 Gran Torino Sport - it is a Q Code 351 Cobra Jet Cleveland, in stock form, it came with 4 bolt mains, cast iron intake and a Motorcraft square bore 4 barrel carb, 4v open chamber heads, flat top pistons, stock hydraulic cam and 9 to 1 compression - by no means was it a power house - not sure what you mean by Boss rotating assembly because mine came with the best stock nodular crank and rods are nothing special
The only thing that really set the Boss 351 or the later HO short blocks apart were the forged pistons, solid flat tappet cam and four bolt mains. The 71 Boss piston was forged and had a dome whereas the 72 HO piston was a forged flat top. The CJ's I have seen had spread bore carbs vs. the earlier 351 Cleveland 4V's that used a square bore carb. The CJ's all had hypereutectic pistons and hydraulic flat tappet cams.
uhh..yup. I cut my little Ford teeth hot-rodding those motors in the late 70's and early 80's. You and Bob surely have it all figured out. Back in the day many guys would seek those short-blocks out to massage and have some extra fun on the cheap. Many got spun, used up and blown as a result. Closed chamber heads with some bolt on goodies easily put you into the 400 horsepower range and 500+ or so when things got more serious with heavy port mod's n such. Even with the lower compression and retarded little hydro-flat stick popping the valves.. still a fun little car, I bet. What power you guys figure with the few bolt on's?.. maybe 230 - 240'ish at the wheels?
I stand corrected on my CJ intake - it was indeed a cast iron spread bore design but someone before I had it put a square bore carb on it causing the back 2 barrels not to align with the intake - it ran good enough for my driving that I never noticed that it was only running on the front barrels - the Boss heads were the closed chamber design with screw in studs for adjusting the solid cam
The Boss's also had different valves in addition to screw in studs. The Boss valves used a single groove lock whereas the standard hydraulic cam equipped Clevelands used a 3 groove lock. To make up of the lack of low end punch, Ford used a higher stall converter on the C6 automatics that were mated to the CJ's. I owned several Cleveland powered cars; a 71 Boss 351 with 4.56:1 gears and a top loader, a 73 Mach 1 with a 351C 2V/FMX converted to a 4V and an oddball 70 Torino 4 door with a factory 4V Cleveland with duals that I modified with a CJ cam. They all ran well, but the Boss was absolutely brutal. Probably the most well balanced of the three Boss Mustangs and my all time favorite Mustang. I owned 2 out of the three and test drove a Boss '9 that was being offered for sale. The Boss 351 was the quickest of the three IMO.
I remember taking my block to our local speed shop to get cleaned and begin the process of building it up to what it is today - the shop owner, who had been building engines and drag racing since the 60's, says "I don't know when the last time I saw a 4 bolt main Cleveland" and his son, who is in partners with him said "Dad, I never saw one until now"
You could absolutely ruin a street driven Cleveland with little effort by choosing the wrong cam, carb, gearing etc. Yes, I know one could say this about any engine, but the 351C 4V was especially fickle. I saw several with off the shelf street/strip cams and single plane intakes that could barely turn the tires in the water box. Properly set up, 1 hp/cu in at the crank was possible back in the 70's IF you stayed conservative with the build.
I wish Ford had saved the $$$ on the 4 bolt mains and given us thicker cylinder walls and better oiling.
boss harmonic balence crank and rods ford perfomace book by pat ganahl explains the difference cobra jets where balanced on the outside while the boss was balenved in the center of tje harmonic balencer and sorry about the spelling im doing all this on a phone cant see what im writing sorry i will post a pic of mine when i had it apart
boss crank rodss and harmonic balencer forged flat tops a cobra jet cam upgraded oil pump runs 75 pds at 2000 rpm idles at 50 pds hot i run it with a 5 speed and 4.11 detroit locker 8 inch rear why use a 9 when 8 inch is good for 500 hp ive had mine for 18 years now has never let me just makes a ratchet sound when making hard left unlocking and locking on a turn typical locker
took me a month to make drvers side header to go around zbar passenger side is hooker part 6913 header made for a 67-68 mustang that needef no altering and use ancor mount made for stock maverick with a 302 had to use starter from 92 thunderbird stock one hits the side of cleveland block when using a five speed also used stock three speed fly wheel from grabber and driveshaft also the shifter also comemes through floor board in same place as three speed so this isnt as hard as some make it out to ne worst part was cuttin shock towers i put 1/4 inck steelplates wide as the shock tower to keep from flexing with botton lemans bar put could be stronger with monte carlo bar as well on the too half thanks for liking this it took me 18 years to finally paint it me and my son 14 yr old did the body work and i have 4 kids and i have a maverick for each one 14 yr old came home from the hospital in this one scared the hell out of thw nurse when i started it he never flinched natral maverick man i said to myself and at 11 he bought his own not wanting to wait until i die to get this one