Hello there.. -I was recently offered a very very nice 68 pontiac firebird.. But it's ofcause with the original 10 bolt 8.2 rear, and I have a 355 chevy (460 HP) and a beefed up 200r4 (good for 630HP) That I wanted to install in the Firebird.. I know that it might be a pity to change the engine, but let's be honest.. -It's much much vheaper to buy parts for the chevy, and since I have it anyway.. My question is ; -will the rearend hold up ? I'm pretty sure that in stock, it won't -but are there any ways to add some strength ? Thanks -Claus...
8.2 hold up Are you installing a rebuilt 8.2 or a stock one that has been under the car since 1968? It will do a good job on the street. If you start taking that thing to the track with slicks and high stall the life will be a short one...How short? Deopends on you and your drive punishment. At least if you snap an axles they will not fly out and damage you , your car or some one else. lol. They had them under the cars in the sixties and seventies with the 455 etc. Give it a shot. Maybe get your self a loop for that drive shaft too. Jim
It has been under the car since '68. -I was planning on installing 3.91 gears w. richmond posi (the stall is apx. 2600) and ofcause putting a new rearcover, w. brace (jeg's have them)... -and if necessery new axles.. What do you guys think ?? Should I keep the original rear, and just upgrade the parts, or possibly buy a whole new rear (which will put me at least 2 grand back).. Thanks for your input..
8.2 rear Well if it were me ...I would determine how original the car is? If it is really number matching car this would definetly be a large concern for me. If you have the money to throw then do the original rear. If strength is all the concern here then build something else stronger 8.5 12 bolt ford etc. Good luck. If you do need any help with parts I can offer some pricing and advice. It may not be the lowest pricing as the big boys but the advise if free. lol Take care and have a great Thanksgiving to everyone. Jim J D Race
I ran a stock 3.36 ratio 8.2 rear in a 3900 lb car with a 3000 stall converter and 9 inch slicks with no problems.. the car pulled 1.7 60' times and went 12.0... i also hit it a couple times with Nitrous right out of the hole with no adverse effects. on the other hand i had a 70 GS455 4 speed with a mildly built 455, tried dumping the clutch at 4500 rpm with slicks and broke one axle and twisted the other. the gears and posi carrier were fine. a 68 firebird is a light car and that small block aint making the torque that a big block Buick makes..you can buy an eaton posi carrier which is much more durable and stronger than a stock carrier. you can buy axles from moser or dutchman...if it were me i'd use the 8.2 until it gives you trouble here is a picture of the new eaton clutch type posi..far superior to the old cone type that came stock in the 8.2 and only 429.00
Just to make sure, if it's a 8.2 -here's a picture of the rear... Could it be an 8.5 rear, posibly ?? -
8.2 Yes it is a 8.2 rear. Very clean too. I would also build it. Looks good and I think with some good parts you will be ok. Jim
My car is an early 71 GS with the bolt in axles. No c-clips. I have 160,000 original miles on the 3:42 rearend, with a bit of racing use with slicks. I realize I'm on borrowed time with it, but with a 4100lbs. car that averages 1.70 - 1.65 sixty fts. I would say 8.2s are plenty strong. Just my opinion. John.
Claus, The '67-69 Firebirds all used Pontiac 8.2 bolt-in axle rearends. The housings in over 90% of these early Firebird rears was the std gray iron housing & the axles were standard duty, not hot forged HD axles used in Pontiac's HD Safe-T-Track 8.2 rears. Like the gray iron 8.2 housings, the stock axles have a limit. To compound matters, many stock axles are chewed up under the bearings, good ol' RW507CR sealed axle bearings seizing & chewing up the the axle HD Safe-T-Track 1st GEN Bird rears... When a 400 Firebird came with 3.55 gearing & Safe-T-Track, or 3.90 gearing (all were HD Safe-T-Track), it came with the HD nodular iron housing. The pinion area of the nodular housing did not move around under heavy load, like the std gray iron housing. Pontiac engineers were smart & moved to address warranty concerns for '67 production by not using the std gray iron housings in at risk (read factory performance) applications. Even '69 Sprint 6 (4bbl) Birds with 3.55 & Safe-T-Track, received this stronger housing & HD axles. Though most of these early Birds are light weight, when such early Birds are built with really strong engines, & the chassis are set-up for rear tires to hook, the original gray iron 8.2 rears just do not hold up. Same with lesser torque engine & a 4speed, torque finds the weak link. Having picked up the pieces from too many 8.2 gray iron Pontiac rears, I just can recommend building them for performance useage. The expense to add new Richmond 8.2 BOP gears, a new Auburn pro series carrier, & often needed new axles will often hit $1200 US. One still has a weak gray iron hsg. Money can be better spent. On a moderate budget, one can go several different ways. 1) Buy a '73+ Nova 8.5 rear built up with quality new gears & a quality posi. Since '91, I've built tons of these. Usually under $800 US. Direct bolt-in, just one will have to shorten the driveshaft with any 8.5 swap. Downside...the '67-69 Camaro 12 bolts & the '72+ 8.5 Nova rears use c-clip axles. Both the early 12 bolt Camaro rears & the 8.5" Nova rears are 1/2" narrower on each side than a '67 through '69 Firebird rear...occasionally this effects big tire/wheel fit. Over the years, have found the "leader posi" Nova 8.5 swap is best suited to cruiser type early F-bodys... running sticky tires & better than 1.90 60 foots, it's time to think of the axles. Same if running a stick & one enjoys speedshifting. 2) Same width 8.5 leafspring rear (2nd Gen F-body) & transfer the 1st Gen perchs. This is the backyard... I gotta welder swap Backyard "builder" whacks off the 2nd Gen perchs & moves them in. Since 1st Gen F-body perchs are at slightly different skew, such hack & whack jobs don't always fit. Have ran into the "it doesn't fit" problem over a dozen times after such goings on. In rebuilding what others have screwed up, have chunked 4 such housings... often easier just to start with a clean 2nd Gen housing. Downside, one still has weak factory c-clip axles & 9 times out of 10, in such a used T/A r/e, the factory posi needed rebuilding. It's not going to hook up well, if carrier is not rebuilt. Many times what some saw as a cheap swap... just cost more $$$ to remedy, than base version of the next alternative... 3) Same width bolt-in tapered bearing axle 8.5 rear. NO c-clip axles to eliminate, or break & tear up a 1/4 panel. Tapered axle bearings provide the best in sideloading. Great for good handling street/autocross cars. Particulars... multileaf or monoleaf perchs reinforced & professionally jig installed. Axle tubes welded to center hsg while in line-up bar. Choice of stock bolt-in axles or Mosers. Choice of 28 or 30 spline posi's or 33 spline spool. Price range $950 to 1500 US. 4) New Moser 12 bolt... either with c-clip axles or with bolt-in axles. 2K plus. Starting to get fairly expensive, though. Hope this helps. :3gears: Roger
