should i go posi track for 383 ?

[Maverick's_Monte]

You've got a great set up so far (aluminum drive shaft...etc.) why skimp on the rear end? I have an '85 with the stock 10 bolt as well and it is coming out in the Spring. I did a lot of research and settled on a Dana 60 that will bolt right up to stock g-body geometry.

I was originally thinking about the Ford 9"but after doing alot of research came to understand that you can get as much reliability and strength from the Dana 60 as you can with the 9". The 9" goes a step further by allowing you to swap out gears with ease using the 3rd member. Thats great if you're heading to the track, but if you're just trying to cruise the street, why pay for features you arent going to use especially if you dont have to? Apologies if the previous comments ignites the eternal Dana 60 vs. Ford 9" debate...

Now, I havent actually installed the Dana yet, the car is in storage for the Winter. But the last trip that leaky, weak, stock 10 bolt will make come Spring, will be to my buddy's garage only to be replaced by something brand new. Thought I share my rationale as it sounds like we have been mulling over similar questions.

To answer your question that started the thread - yes put a posi rear end in regardless of what style housing you choose.

 

[565bbchevy]

Okay so I did some research the 9” ford rear axle with Moroso spindles comes out to be like 900 which is not bad but question is do I really need it for a street/everyday driver? I will be using a built 350 turbo with a 3500 stall converter, aluminum driveshaft, so do I really need that rear end ? and well I could I just do a limited slip on the stock differential? Overall I am pushing 450 to 475 hp torque around the same.

If $900 is just for a new housing with axles(probably Moser not Moroso (spindles) that is the average price, if that's what it is you will still need a case(Nodular) your choice of gears,carrier, yolk, misc, etc to have a complete rearend plus a rear brake set up. Figure $2000+ for a new Ford 9" depending on parts.

Now I personally use a Detroit Locker in my 9" on the street to handle the power I have and it has worked perfectly for 12 years now. Also some people confuse a Locker with a Spool. A Locker unlocks on a turn and fully locks going straight where a Spool is always fully locked and will rip up the inside tire on a turn since it still turns the same amount of times as the outside tire.

 

[MrRabbit24]

87 cutlass supreme with a 307 all original,would its rear work better ? Its a v8 rear
Axle right? Better than the 7.5 and just throw a detroit locker and call it good ?

 

[565bbchevy]

87 cutlass supreme with a 307 all original,would its rear work better ? Its a v8 rear
Axle right? Better than the 7.5 and just throw a detroit locker and call it good ?

It will still be a 7.5 there are no V8 or V6 rearends, the 8.5 came in limited models like GN,Turbo T-Type ,Hurst Olds,442 etc which are V8 and V6 models.
It really comes down to your budget and knowledge, if you have enough money you can buy a complete bolt in rear end that will handle any power you throw at it.
But if you have the knowledge to assemble a housing and install it in your car then you save a lot and all your money goes into quality parts instead of labor.
If you are on a budget and lack the knowledge then I would suggest taking your car to a ring and pinion shop and just have them install a gear and posi in your 7.5 and you can later add a support cover and have someone fully weld the axle tubes.
Plenty of people have stregthened their 7.5 to handle decent power but there are limitations.

 

[MrRabbit24]

Okay were can i order a 9” ford axle with everything ready for swap? Ebay,summit ,jeggs? And Will my rims still work with the rear axle?

 

[565bbchevy]

Okay were can i order a 9” ford axle with everything ready for swap? Ebay,summit ,jeggs? And Will my rims still work with the rear axle?

Moser Engineering and Currie Enterprises are a couple I know of that will send an assembled rear end to you.
They come factory width meaning your current rims will fit the same, you can also get custom width rear ends.
I would suggest doing as much research as possible there will still be options that you have to select and if you don't know what you want or need it will be hard to answer.
I would contact them direct and discuss with them your plans for the car.
A complete rear end with brakes will be at least $3000+ and will have to be shipped truck freight(another fee)

I honestly think unless you funds are unlimited that you should maybe take your time and search out a complete gbody 8.5 rear end and upgrade that since it will come with brakes which will be just an option on bolt in 9" or 12 bolt. And it will be plenty strong for application.

My 9" I bought everything separate and assembled it myself using a Moser housing/Axle kit ,nodular case, Detroit Locker, Wilwood disc brakes, I welded on a brace and added a fill cap an drain plug. Because of doing it this way I get the best price on individual parts and everything is shipped UPS.

I personally like the 9" over any other since the center section comes out easily if you want change gears etc.

 

[MrRabbit24]

Well i just want to say thank you very much for all the info and everyone else as well i greatly appreciate it and i will give them a call i will probaly end up buying it assembled i just dirnt want to order the wrong parts again thank you.