can you use you stalk 1968 mustang differential on 390 swap
You can but remember it is stock so it won't handle full 390 power for long. I'd put in a Ford 9 inch at least.
What was the original engine. 6 cyl's had 7.5 rears, while small block v8's had an 8" with the 9" optional.
If your car originally came with a 289 or 302 you have an 8" rear in the car. You CAN use that with a 390 if you want, but long term durability would be better if you used a 9" rear. The 8" units are much more durable than they get credit for, the weaker links are the rear U-Joints used with them and the two piece rubber lined drive shafts that are used with them. With a pinion yoke swap, larger U-Joint, and a driveshaft upgrade, the 8" does very well in higher horsepower and torque applications. If your car originally came with a 6 Cyl. engine, I wouldn't recommend keeping the tiny rear end in the car and expecting it to hold up very well for any amount of time. Regardless of what the original engine WAS, installing a 390 in it's place will be a VERY expensive adventure... considering all of the OTHER things on the car that will have to be replaced just to make the swap happen. Even if a 390 engine was available to you for FREE, you'd be looking at spending several thousand dollars on the car just in small parts and minimum upgrades to existing components... just to complete the swap and make it somewhere near "Correct". At a minimum, you will need motor mounts, a transmission crossmember, a radiator and mounting brackets to mount it.... a driveshaft of the correct length, a new sway bar, a new gas pedal arm and throttle rod, a new floor shifter to Trans rod (C6 auto?), new front coil springs ... etc. etc. Upgrades will require a complete new braking system on the car at a minimum, and new rear leaf springs also. If you can find a 9" rear for the car at a reasonable price, I'd say buy one... but with so many OTHER things you'll need to do a 390 swap, I'd put the rear end at the bottom of the priority list. Some of the pieces and parts you'll need to buy are HARD to find and very costly when you do get them... don't run out of money on a rear end too quick, that can wait (my opinion).
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