I am about to buy either a 65 or 69 Coupe (considering a 70 Fastback). I plan to put a mild 377 crate engine in it. I am wondering if a 9" rear is worth the money and effort if I do not plan on racing around.

If so, how difficult is this install and do I need a new driveshaft?

 

Unless youre planning to go crazy with it, I wouldnt put money into a 9" rear. An 8" should be fine as long as you dont get above 300-400HP. If im wrong please correct me.

 

The 377 is rated at 475HP

 

minus about 25 through the drivetrain so we'll call it 450 to the wheels.

i think a built 8" would work, but a built 8.8" would be better. and cheaper than a 9" i think

 

Yeah, I was guessing anywhere between 25-40 HP through the drivetrain. I think that would be plenty of pep for a weekend driver. Is it better to go to a junk yard and grab the rear end and have it built? Or buy new?

 

have it built or build it yourself. I would probably cost you less

 

Your close to the line on what a 8 inch can take built to hell a 9 inch might be better if you want to keep the car a long time.I'm not a 8.8 fan id run a 12 bolt gm or dana over one.

 

you have a link for the dana?

 

Dana you'll have to cut down and make fit there mostly in dodge and 1 ton trucks.For a 9 inch http://www.perogie.com/Rears.htm and many other online mustang junkyards can sell you one.

 

If memory serves me correctly, the old Crown Victoria 9 inch may serve your needs with little modification. I would research this possibility given that there may be many in junk yards and it may suit your needs. Maybe Andrew or others may have insight into this.