8 1/4 how durable?

[flyinbrick68]

Well had my bro send me a pic of the rear in the fury as its in ks in his shop for storage... kinda got screwed the guy i bought it from said it had an 8 3/4 looks to be a 8 1/4. How much torque can the smaller rear handle? Will it hold up to a 451 or am i going to have to swap in an 8 3/4 or have dana 60 built? I'll try and post a pic tomorrow when i can get to my comp. Maybe i should get to measuring theother rear in the spare d100. Time for me to invest in a fsm!

 

[flyinbrick68]

Well from what I can gather and I don't have a fsm the 72 rear end should be 64 3/8 drum to drum and the rear from my 70 d100 is 64". Time to hit up the local salvage yard here and see if they've got a c body rear. If not a 72 to 74 dodge truck rear should fit being its 64 3/8 wide. So on my days off its down to ks to do some measuring and get the widths ect yay.

 

[commando1]

You can only break an 8-1/4 by by flooring from a dead stop.
Is he going to floor it from a dead stop?
I had an 8-1/4 behind a 500 hp 440 4 speed.
It didn't break.

 

[flyinbrick68]

only on the track maybe itl work then...thanks and i don't think my heads will flow enough to hit the 500 mark. Till can afford a good set of aluminums that is.

 

[commando1]

Run it till it breaks. If it breaks at all.

 

[commando1]

I have no proof that my 440 had 500 hp.
The guy whom I never met before said it had 500 hp.
I told him I needed it asap because I was moving out of state in two days.
He wouldn't have lied to me........

 

[flyinbrick68]

Doubt ill be putting down that much power but hopefully a bit of torque. It'll get to the track a few times a year. I have to drive 120 miles or so to get to one, ought to be an adventure! So it will be stomped on once and a while to take advantage of the stall converter. Ill keep looking for me info and try and do some more research. Thank you for the personal experience makes me feel a bet better anyhow.

 

[Wollfen]

Well from what I can gather and I don't have a fsm the 72 rear end should be 64 3/8 drum to drum and the rear from my 70 d100 is 64". Time to hit up the local salvage yard here and see if they've got a c body rear. If not a 72 to 74 dodge truck rear should fit being its 64 3/8 wide. So on my days off its down to ks to do some measuring and get the widths ect yay.

Personally i wouldn't be bothered by that 3/8's of an inch you are losing, whats more important is checking the spring perches to see if they are the same width, if so, bolt the D100 unit in and you are good to go. If not, cut them off and reweld them in to the correct width for your car. That 3/8s translates to losing about 1/4in either side.

 

[Polara_500]

I've done worse and got away with it. Stuck a 69 Roadrunner rear end in a 65 Polara, just bolted it in - yeah, the springs bowed in nearly an inch on either side, but I ran it that way. Okay, so I was younger and dumber then, this was around 74 I think and we didn't have the available knowledge base we do now. Hey, the rear end lasted nearly 100K miles before I sold it, and it was still running just fine then. Did look a bit strange, but oh well...... That poor car had a rough life once I got my hands on it.

Not that I'm recommending this course of action........ (Disclaimer)

 

[flyinbrick68]

I suppose that means with the right offset I could mount in a wider tire cause the rear is narrower or use a spacer which would probably mean longer axle studs.