So now that I got all this mayhem from how crappy the I6 axle is .

1965 Mustang

I want to know what other modifications i need to do to the car to change it into a 9" rear end .

how much am i looking at ?

All i know .. is you need a rear axle and driveshaft and minor components that go with it .

I was thinking of finding one at a junkyard and just replaces all the bottom end of my car ..

Cuz while im at it . I can put in a dual exhaust ,

BTW does anyone know of a good Junker in So Cal ?

 

If you get an axle that fits dimensionally, ad has the spring pads in the right place, all that you will need to do is bolt it up and change the driveshaft, (or the end of the driveshaft)

 

You don't just 'convert' to a 9 inch rear axle for a 65 - first you find one. There were less than 20,000 9 inch rear axles made for 64 to 66 Mustangs. Most went into Hi-Po or Shelby Mustangs. The remainder were factory special order orservice parts. There is another year Ford that used a 9 inch axle that will fit an early Mustang, but that one is as rare. You can buy a custom made 9 inch housing, either made from scratch or modified from another year - they are expensive.
Options -
1 Get an 8 inch rear axle. They can handle 500 HP with the right kind of setup.
2 Get a 9 inch axle and have it modified.
3 Wait.
Jim

 

Well I have a local source of getting junker cars and parts... like a 9" ..

I was going to buy one about a week ago .. but i didnt think i would need it until i realized i didnt have an 8" .

And by then it was sold . So i kinda ran out of luck ..

But while im at it .. I basically have to change the front axle too so i can all around not need new springs etc... and all of it will come from a junker car .

as well as me getting brake disk from it .

what 9" were compatible for the 65?

 

check the faq theres a link in here showing how wide your axle is and what other cars got the 9 inch and how wide they are. honestly id go for a 8 inch cheaper to get cheaper to rebuild and they can hold more power then you think.you dont want to know how much i spent on my 9 inch i used a currie housing.but i had to im around 600hp and i have a problem i never leave things alone im geting a blower soon i think. even my truck has a big block with a tunnel ram. can that be a metal problem lol.

 

well im only at 300 hp and almost 400lb tq.

i dont want to have to rebuild or mod the 8" .

i much rather just buy a 9" and have a safety boundary.

 

im 600hp 575 foot pounds a 8 inch can take that with a good rebuild with the right parts.besides if your geting a used rear end you have to rebuild it. you dont know what shape its in and why take it out again when you dont have to.its up to you its your car your money either way will be ok.

 

I would just rebuild the rear end you got. Maybe get an axel that can take the power and since your rebuildin it (if you do) maybe go with a posi spool. But if its just your DD, diffriental would be good. I dont see a 9" bein much of a "safety boundary" when that 8" is perfect for your power you got.

 

You'd have a better chance of getting struck by lightning thanfinding a useable 9" complete rear end to fit a 65-66 in a wrecking yard today. Don't go get a later year, or another Ford model rear and stick under there that is the wrong width. You'll just be fighting rear wheel offset and tire clearance issues from now on.

If you have the money, then contact Currie and buy yourself a new 9" rear. Plan on $2500...

Otherwise, listen to the advice given here and stick with an 8". You're too new into this subject to argue

 

You can do it fairly cheap, just get the correct width housing from someplace like currie, strange or moser. Hit the wrecking yards for a truck 3rd member, look for one that has a trac-lok. Figure out what spline axle it has and get matching ones to your width. Rebuild kit for the posi, most trucks have decent gears. Housing will run you around $400, $300 for axles. No clue on the 3rd member, I used to be able to pick them up for $50 from a local truck wrecking yard.