Rear end ???

[MonteNH]

I am installing a 454 in my 72 Monte. I was told I should up grade the Rear End and Tranny.

 

My rear end is a 10 bolt non posi.

 

Can this rear end be made into a posi by buying a posi unit and new gears ?

 

I dont plan on ever racing it just a fun street crusing car.

 

I want to eventually add a muncie 4 spd down the road also.

 

 

Thanks in advance, Phil

[Sam (Bones)]

your 10 bolt will be fine, but if you start throwing some drag radials or slicks at it, that's a different story

[LS5]

Hey Phil, Sam is right that 10 bolt should be ok, it depends on what coin you are looking at to put that set up in? as it might be better to run a series 3 gearset in a 12 bolt...I have a 454 and a M-21 and a 331 12bolt rear and all is good especially on the Highway driving plus thats what is on the build sheet too..If you think you are going to want to have some get up and go more often that what you thought at first it doesnt hurt to go 12 bolt and a swaybar with boxed control arms that way you can let the grrrrrrrr out....

Darren.

[MonteNH]

Ok , so I can just buy a posi unit and some gears and turn this rear end into a posi rear end ? Sorry for the questions just unsure which way to go.

 

I'd rather not have to buy a whole new 12 bolt and have that installed. Its easier to drop the car off somehwere and pick it up all done rather then drive around looking at rear ends I have no clue about only to find out I bought the wrong part.

[ScottNM]

Plus you do not always know the exact condition of buying a used one. It is 1100.00 to have a Posi carrier, ring and pinion gear and all new bearings/seals installed in my single leg 12 bolt unit. I am thinking it over myself. Then you need to box the arms I believe.

[Big Jim]

That's me. I ordered the parts and had my mechanic install them.

I had it all changed and it was around $1100.00.

[MonteNH]

Would I need to box the arms if I kept my 10 bolt and just ordered a posi unit and some gears & bearings ?

[Sam (Bones)]

sure wouldn't hurt, they have the "plates" available aftermarket, easy to weld in

[bigtankjones]

I run an Auburn posi unit with 3.73 gear in my 10 bolt. I have a Big Block 454 that is bolted up to an turbo 350. No boxed control arms. I have never pay'd any attention to my gas mileage. But as long if I dont abuse it it seems pretty decent. But when I do get on it. It likes to go wicked sideways.

[MonteNH]

Thats exatly the set up I would run. My car has a turbo 350 and im dropping in a 454. I want to add the posi with 3:73 gears.

[bigtankjones]

I think you will like it that way. Allot less money spent to.

[MonteNH]

Does Your car get up and go with that set up ?

 

Nice looking car BTW Bigtankjones....what are You running for rear tires ? I like the stance.

[ScottNM]

I think you will be miserable on the highway with 3.73 gears. 3.42 gearing for a BB max. You have enough low end torque without it.jmo

[cbolt]

That's me. I ordered the parts and had my mechanic install them.

I had it all changed and it was around $1100.00.

 

 

Was that the total price for the parts and the labor? I have ordered my 200-4R and am currently shopping for the best and most cost effective way to upgrade my 10 bolt to a 3.73 setup so all this is very interesting to me.

[Big Jim]

I think that was parts. Check with Randy's Ring & Pinion.

[cbolt]

Yea, that sounds about right for parts which is why I had to ask