81 Malibu "Uncaged" Performance Therapy project

the work you did to make that differential look better is impressive, the pictures show the effort was sure put into making it look much better.
I,'m rather curious as to the power level you intend to run thru that rear differential, the reason is that I had a long drawn out learning experience that involved, the need for a series of rear differential upgrades, in the past that required keeping ever stronger rear differentials in a 1967 Pontiac fire-bird ,
that has forever left me with the UN-erasable conclusion, that a stock or mildly modified 10 bolt 8.2-or-8.5" rear is about as indestructible behind a serious engine,
(once you install decent tires and traction bars) as a potato chip is on an anvil with a 12 pound sledge hammer.
I replaced my original 10 bolt differential, with one, I purchased from a similar car in a salvage yard, that was professionally upgraded at what I thought at the time was a huge cost, it was built with aftermarket axles ,better bearings bigger brakes etc. and I managed to shred the ring & pinion in only a few days of racing and that never involved a car launch at over 2500rpm with a 421 Pontiac that I had built, which I doubt exceeded 500ft lbs of torque, and 3.73 rear gears.
I eventually upgraded to a 12 bolt camaro rear but that eventually also failed, after several upgrades in power,only the dana 60 from a 1970 cuda held up


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67-70 Firebirds had the 8.2 BOP 10 bolt unless they were performance models that came with the Chevy 12 bolt. The 8.2 wasn't considered a very good rear for high torque applications especially combined with manual trans, traction devices, and slicks. I'm not surprised you had failures with the 8.2's but don't understand why you had problems with the 12 bolt unless something wasn't right or you had ungodly torque and traction. I do have a 12 bolt leaf spring rear from a 2nd gen F body I took out of my 74 Camaro when I sold it and if I have problems with the 10 bolt I might consider it but I don't think this set up will need it, 10 bolt should be OK.

The engine will be what I consider fairly mild as far as power goes. It's one of the high nickel 010 small block 350's that will be .040 over (roughly 357) and decked. 993 heads with 2.02 1.6 valves, screw in studs, mild port job. TRW forged pistons, stock rods reconditioned and smoothed, and balanced rotating assembly. Probably a Performer manifold & Holley carb sparked by an MSD system. I might put a small nitrous kit on it eventually but it wouldn't be used off the line.

I've got a couple T-400's to try and both of them came out of running/driving hot rod type muscle cars with shift kits and perhaps other upgrades (one of them is from TCI). Haven't made a choice on the torque convertor. Drive shaft will be made by a local driveshaft shop I use up in Lantana with stock yolks and I'll make a couple driveshaft loops in case a yolk or U-joint fails, figuring they'll be the weak link. I'll be footbraking at the strip with an automatic so there won't be the shock of a trans brake or side stepping the clutch and I'll probably be on Hoosier A6's (auto-X tire) or ET Streets on some Centerline big & little's I have.

The rear's had the axle tubes welded to the center section and will have the stock used 28 spline axles and LSD with new 3.73 Richmond gears unless I can find a deal on some used Moser axles. Probably have one of the extra capacity aluminum covers with the bearing supports IF I can find a deal on one. Aluminum drums will help lower unsprung rotating weight and MOI. All bearings etc. will be new.

Rear suspension is the Hotchkis upgraded 4 link with stock style lowered coil spring setup. There are some G-body mount upgrades I may do along with a frame notch so I can get a bit more tire under the car. Air bags came with the kit for strip use. Don't know much about using the bags so that'll be a learning curve.
 
sounds like a well thought thru set-up, I hope it works out for you and you don,t have problems, and
yes I fully admit that I had the largest slicks I could find at the time and slapper bar type traction bars and a muncie 4 speed and a 35 lb flywheel and no where near the driving skill at the time required to launch correctly which IM sure contributed heavily to the parts breakage issue at the time I was in my early 20s
my Dad at the time commented, after visiting during the constant repairs that I seemed to have "the ability to break an ANVIL with a rubber mallet" all part of the learning curve! where you learn BOTH what works and what costs you money as you gain skills thru trial and error... but thinking back I don,t think Ive ever met or heard of a 20 year old with a 400hp plus car that didn,t have that or a similar skill or experience
 
Sometimes we learn the hard way grump. Hopefully the kids growing up with the internet who become car guys can learn from the mistakes we made by reading on forums like this.

At this point I've brought this project up to date here. The rear end housing is sitting on my bench gathering dust awaiting assembly and I need to spend some time at the machine shop to get the engine finished. The car has been sleeping in an enclosed trailer the past few years waiting to be reborn. I ended up getting much deeper into the Firebird project than I had planned when I started it and the Malibu got kicked into the corner so to speak. I'm almost finished building a kitchen I've been working on in my spare time so hopefully the Malibu will get some attention.
 
grumpyvette said:
sounds like a well thought thru set-up, I hope it works out for you and you don,t have problems, and
yes I fully admit that I had the largest slicks I could find at the time and slapper bar type traction bars and a muncie 4 speed and a 35 lb flywheel and no where near the driving skill at the time required to launch correctly which IM sure contributed heavily to the parts breakage issue at the time I was in my early 20s
my Dad at the time commented, after visiting during the constant repairs that I seemed to have "the ability to break an ANVIL with a rubber mallet" all part of the learning curve! where you learn BOTH what works and what costs you money as you gain skills thru trial and error... but thinking back I don,t think Ive ever met or heard of a 20 year old with a 400hp plus car that didn,t have that or a similar skill or experience
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yep my first turbo zx i busted a close ratio 4 speed ( that one was completely ruined, not just a little grinding but catastrophic failure) then i ate a borg warner t5 in short order after replacing the four speed... rigging a 99 v6 mustang afermarket shifter with properly set shift stops prevented this from ever happening again, i use to break my knuckles open on the radio shooting third every time with the stock shifter...
 
Very similar rear to whats in my chevelle drag racing launches on slicks or good stick tires kill parts PT build for auto cross won't let you run that sticky of a tire if the idea Ultimate street car style rules. Had long talk with my friend who grew up at the track about that and yes if you don't have give at those tires parts break. Butif you run a protouring not as much as drag radial spinning tires before breaking parts.
 
Since the 2008 crash thoughts of Bullet proof Rearends have not been done with most builds John.
Guys run out of $$$.
Most can't afford an original Mopar B & E body Dana 60 today.
$2,500 low ball to high of $10k.
Strange Dana 60 also but most can't afford also.

Stocked up in 1957-64 Pontiac 9.3's.
1 Dana 60 rear I have also with 4.10 posi.
 
i wish i had the hot rod parts resources you guys do... everyone in south and central florida knows what they have and its all squirreled away for themselves and their friends... the guys that do sell want a billion dollars for the shit. theres hardly ever a good deal on a bad ass part anywhere within a reasonable drive for me.
 
philly said:
i wish i had the hot rod parts resources you guys do... everyone in south and central florida knows what they have and its all squirreled away for themselves and their friends... the guys that do sell want a billion dollars for the shit. theres hardly ever a good deal on a bad ass part anywhere within a reasonable drive for me.
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Have enough Poncho 9.3 rears I could build a few for others.
Sell at decent price.

Not selling them shit.
Almost ashamed to be a Corvette Owner.
Thank God I never sold my Pontiacs.
 
87vette81big said:
philly said:
i wish i had the hot rod parts resources you guys do... everyone in south and central florida knows what they have and its all squirreled away for themselves and their friends... the guys that do sell want a billion dollars for the shit. theres hardly ever a good deal on a bad ass part anywhere within a reasonable drive for me.
Click to expand...
Have enough Poncho 9.3 rears I could build a few for others.
Sell at decent price.

Not selling them shit.
Almost ashamed to be a Corvette Owner.
Thank God I never sold my Pontiacs.
Click to expand...
Sad my pontiac is gone but make due with chevelle at least it was my fathers first that gives it value alone
 
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