• Hello there guest and Welcome to The #1 Classic Mustang forum!
    To gain full access you must Register. Registration is free and it takes only a few moments to complete.
    Already a member? Login here then!

302 auto vs standard

Rob Z

Member
I have two Mustangs. Both with 302s. The '69 has a C4 and the 70 has a 3speed.

The 69 engine is near a rebuild. Just getting a tad smokey. The engine is already out of the 70 and rebuilt. My thought is to pull the 69 engine and install the 70 rebuilt engine in the 69. Then I can take my time rebuilding the 69 to put in the 70. Confused yet :craz

These are daily divers. Nothing special and will not end in a show or ever be worth a lot of $$.

Question - Is there a difference between the cranks which would hinder this swap? Or anything else I'll have an issue with??

Thanks
 
The difference will all be bolt-on options, with a very possible exception of the heads. The '70's most likely have positive stop rockers, and the '69 likely will be fully adjustable.
 
Find a 5.0 roller block, much nicer in the long run. Most only need a good honing and re-ring with cam bearings and freeze plugs to be ready to go. :amaz
 
"gwstang" said:
Find a 5.0 roller block, much nicer in the long run. :amaz

OK, I've seen this reference but lost in actual info. Please define a 5.0 roller block???? :craz

Did it have a roller cam, rockers etc?? What years and or cast numbers.

Thanks
 
A roller block is referring to a roller cam. IIRC, it was the mid 80's that ford swapped over to it. The only issue you would have is putting it in a vehicle with a manual tranny. They don't have the threaded hole on the side for the Z-bar. The fox body mustangs use a cable for the clutch.
 
"66gt350" said:
They don't have the threaded hole on the side for the Z-bar. The fox body mustangs use a cable for the clutch.

So what would be involved in changing to a cable? Is it simply going to a cable or a bunch of fab work? This is my first standard car so that part I'm learning as I go.
 
I can't help you out with the cable conversion. I'm running a McLeod hydraulic throwout bearing. But there's gotta be several people here who are running a cable.
 
One modification normally leads to another and this is a prime example.

Without the Z-bar mounting location on a roller block, yes, swapping to either a cable or hydraulic clutch mechanism is an option.

Using a cable operated clutch has more drawbacks. You'll likely have interference issues with the cable running too close to your exhaust manifolds/headers. Your pedal assembly will need to be modified to mount the cable.

The hydraulic mechanism has no issues other than cost.


If it were me.... I'd focus on just swapping the two engines that you already have. As previously stated, the largest issue you're likely to encounter would be the hassle of swapping all of the front of engine bracketry, but this is usually just a matter of getting all of the brackets lined up the way they need to be.
 
I think Dave is reading my mind. Althought the roller sounds good I think just the engine swap is my best course. As I plan on taking everything off the 69 engine and placing it on the 70 engine all should ne good.

Thanks to everyone for their thoughts and help.

Planning the wap for 3 weekends from now... I think :amaz
 
Be aware that the motor from the automatic car will need to have a pilot shaft bushing installed in the rear of the crank, and the manual motor will need to have the same removed to fit the torque converter to it. Both the 69 and 70 cranks will be drilled for this from the factory. Other then that it is a bolt-in as long as you are using all the outboard parts from the correct car.
 
Back
Top