: 8.5" 10 bolt rear axle
Mar 25th, 00, 03:52 PM
I have an RS67 and I plan on running a 500hp big block with a 700R4 trans. This will also be my daily driver. I currently have an 8.2" rear axle and have been told that it is weak and will not hold up. I know that a 12 bolt would be the answer but they are getting pretty scarce. I remeber reading in a car mag that the 8.5" 10 bolt deserves more credit and one out of a 72-74 Nova will bolt right in. I could get 5 of those in a junk yard right now. Should I get an 8.5" 10 bolt and get it built and use one of those "rear end support covers" or should I hold out for a 12 bolt??? Any info will help. Thanks!!
Mar 25th, 00, 06:10 PM
You will not get any respect with a 10 bolt, but your wallet will like you more. As you stated 12 bolts are hard to find and VERY expensive. If I was in the market for a rear end I would get an 8.5 in a heart beat. Ask the person shop that sets up your rear end if you need the support cover. While you are at the junk yard see if you can get a posi carrier out of a Trans Am.
Mar 25th, 00, 11:08 PM
The 8,5 incher will do just fine.
Forget about the rear support if you wanna get serious.
In that case you should make up a set of new maincaps outta steel for that axle.
Iīm pushing my 8,5 in a serious way,and have been for the last couple a years or so.
Works great so far,but in all honesty i change bearings aso on a routine basis.
More important then the carrier support however, is that you get the tubes and perches welded.When you start making the car hook you run a fair chance of making the tubes let go.Itīs happend to me more then once.
I strongly recomend getting someone to weld them with a TIG if you donīt have one yourself.
Have the gear setup by someone who KNOWS what heīs doing,and be frank about your intened use of the axle.
482 cubes of fogger injected thunder in a 71 z.
Mar 26th, 00, 10:39 AM
I also have an 8.2 rear end, and I was wondering. How much power will they handle?
Mar 26th, 00, 06:43 PM
I think I will go with the 8.5" and buy a good posi unit with the money I saved from not buying a 9" or a 12 bolt. I do have a local shop that will setup my rear, all of the local racers take their cars to his shop so he must be good. I have a mig welder but not a tig so I guess I will have to take it to somebody to get the tubes welded up. Steel main caps?? Are the stock ones cast iron?? Thank you for all the feedback.
Mar 27th, 00, 04:26 AM
Racing, I love that movie file of your black camaro doing that hard launch and then the serious wheelie. I thought it was soo impressive that I showed it to all of my car buddies, their only response was "let's see that one again ..... again .... again ..... one last time .... again"!! Way cool!!
Mar 27th, 00, 06:16 AM
i remember seeing in CHP there was an article on the rear end swap setups. try to get a bare housing if possible. then get the posi from a 70-81 trans am. get the gears 3.42 from an 81-90 1/2 ton pickup. they all should have 8.5 rears. i am on the quest for hte following parts and i know where i can get the gears and the posi, but so far the housing has not turned up yet. total for the parts should be @ $200, but it takes some careful yard hunting. as for the brakes and axles should still work. when i finally find the right housing , i will try the setup and see if it will work.....
Mar 27th, 00, 08:14 AM
Credit where creditīs due..
Not my 1.st gen in that avi.
Friend of mine however.
I got a couple a 1:st gens tho..youīre right there http://www.camaros.net/forum/biggrin.gif
That 10 bolt iīm talking about is the one under olīsloī.
Yup,the OEM caps are detroit wonder metal..
482 cubes of fogger injected thunder in a 71 z.
Mar 28th, 00, 12:33 PM
I think a lot would depend on how well your car hooks up. I put an 8.5 10 bolt from a 73 Nova, with a posi from a Monte Carlo under my 68 and run 12.50's with no problems. I know of others that run alot quicker than that with the 8.5. If you're running slicks with that much hp you might have problems, but for the money I'd still go with the 8.5. BYW, use the multi-leaf springs that come with the later model axle, they're light years better than the single leaf(if that's what you have) You have to use the original front spring perch from the camaro, but everything else is a bolt in. Good luck
68 SS Camaro
73 Nova Hatchback
Mar 29th, 00, 04:57 PM
what year monte did you grab the posi from? i was told that all late models have 7.5 rear ends...also what were the gears?
thanks JS http://www.camaros.net/forum/confused.gif
Mar 29th, 00, 08:55 PM
73-77 or 78 Monte Carlo's came with 8.5" rear ends. When they were downsized they got the 7.5 rear end.
Apr 5th, 00, 09:21 AM
If you a really putting a 500+ hp motor in a 3000+ car I would really recommend a high quality assembly. I am currently looking at a Currie unit with either a 9 inch or a modified 12 bolt with 9 inch tubes and axles for around 2000.00 Very pricey but I just can't digest the idea of going with a junk yard or pieces/parts unit that I have to wonder each time I put the pedal down that the darn thing will explode and I end up driving my car into a ditch. Heck if you can afford a good 500+ hp engine (5K to 10K), a 2k axle is cheep insurance but we all have budgets that usually make up about 50% of the choice on what to buy. http://www.camaros.net/forum/biggrin.gif
Apr 5th, 00, 11:04 AM
AMEN Toby!! With that kind of horses gearhead it most deffinately be wise to place a substantial rearend in the car. A fresh 8.5 would prob do but is chancy. Have you ever seen a rearend give it up under that kind of power/torque? It will make ya think about things http://www.camaros.net/forum/biggrin.gif Food for thought http://www.camaros.net/forum/wink.gif
Apr 8th, 00, 07:09 PM
Ok .... I got the hint and you guys are right about the money part. I am going to wait a little longer and save some more money and do it up right. I did not want the rear to be the weak link and I also did not want to worry about it. I think I will just have to use quality parts in a 12 bolt and not have to cross my fingers. My buddy in Hawaii located one for me but I have to get it narrowed to fit. Thanks for all of the input .... any pictures of that rear axle that gave up??
Apr 8th, 00, 07:33 PM
I know this is off the subject but it has been bugging me for a long time. Does anyone out there have an honest 600hp motor or more (n/a, blown, or nos) and run a 700R4? Please answer only if you really have this setup. I am interested in the extra gear over my 400 but am very concerned with the stories I am hearing. And these arent from users but the trans builders I have been contacting. If someone does have this combo how long have you had it setup and what level of traction do you have?
Apr 9th, 00, 06:37 AM
have the t-shirt "been there , done that" had a pinion gear go out the bottom of the housing....big mess,got an 8 3/4 A body rear with 4.10's and a sure grip....gotta install it...so get the best you can afford,it will be worth it in the long run.
Apr 9th, 00, 10:39 AM
Has anyone looked at getting a 12 bolt pickup diff and narrowing it? You could replace the axles with stronger aftermarket ones instead of shortening and re drilling the origonal ones.
I've heard the pinion is smaller stem size though.
Apr 11th, 00, 05:56 PM
Pink 68, check out http://home.earthlink.net/~mutert23/ he has about 550hp and is loving it. He also has his email on the web page if you want to ask him questions. He is a nice guy and has already gave me a ton of information regarding his own modifications. Enjoy!!