[Cougar72]

Ok this one is for the motorheads. What is the difference between the HO(High Output) and CJ(Cobra Jet) engines from the 1972-73 Mercury Cougar and Ford Mustang. Both are 4bbl and the HO has more horses and torque, but other than performance gains are there any other differences between the two? Also, how can you tell the difference?Thanks
:1poke: Kyle:1poke:

 

[dark7068]

The CJ has 4V ports and valves, but 2V chambers. HO has adjustable rockers but has a cumbustion chamber of 75.4cc
Kinda easy to ID now you know what to look for.
CJ number for heads is D1ZE-DA, and HO number is D2ZE-A, both heads have 75.4cc chambers and 2.19/1.71 valves.

Rick

 

[dark7068]

Also, the HO has a solid cam, retarded 4 degrees or so, to go with the adjustable valve train.

Rick

 

[skater32]

HO vs CJ

HO is actually a lower compression (and other slight changes) Boss 351 -- it shares a lot of the same parts. It was VIN code R, only available with a 4 speed and only in a Mustang. You can ID it by the heads (machined for adjustable valve train) and many parts with D1ZX or D2ZX casting numbers.

The CJ is a plain ole 351C-4V. VIN code Q, available in lots of vehicles with M/T or A/T.

Cheers,
Dan