Oph Rear Question

Discussion in 'Got gears?' started by BA, Nov 9, 2004.

  1. BA

    BA Well-Known Member

    Help! Help!

    I heard you are the resident expert on rears.
    I have a set of 4:30 8.2 gears that are part #1385409 pinion & part #1385403. Will these fit my 70 8.2 rear?

    Thanks,

    Bill
     
  2. David G

    David G de-modded....

  3. gscalifornia

    gscalifornia Small blocks rule!!

    Though I'm not an expert my understanding is things were the same until the change to the 8.5 in '71. So, the gears in the 8.2s should fit but you need the correct posi carrier for the low/high ratios.
     
  4. GStage1

    GStage1 Always looking for parts!

    4.30 gears?? Are you planing on running the 1/8th mile??

    That is way too much gear for a street car. Better off with 3.42
     
  5. BA

    BA Well-Known Member

    Thanks guys,
    George I had a Chevy 12 bolt with 4:56's in my street GSX with a S.P.TH400 when I first bought it and yes they were way too big :eek2: I had to watch the "Rev's real close. They certainly were fun for a while. I also do have the original rear,but would like to build up a spare rear with the 4:30's if possible.
     
  6. flynbuick

    flynbuick Guest

    We had the factory 8.2, factory 4.78 performance gear in our first stage 1 GSx. Street car too. Ridiculous gear I used to say. We changed it to a 3.23 and it still would burn the tires off.
     
  7. 66skylarkpost

    66skylarkpost 430 powered '66 skylark

    4.11's behind a 430

    i got 4.11's behind my 430 (mild buildup) , with 400 turbo , yet i only drive it on the rarest occasions. but it sure is fun , watch the rpm's .
     
  8. oPh

    oPh Well-Known Member

    The part numbers & 43-10 R & P are def Buick.

    Regret not being able to get on here & post.
    When my home computer was up & I could get on the laptop or a computer while out on the road, could not post. When we reloaded the 'puter with new harddrive in late Sept, did not format my home e-mail right, & when Jim W reformatted the board, my e-mail to the board bounced & I had "priveleges revoked". Can laugh at it now...sometimes wish I knew 10x more about 'puters & less about cars :laugh:

    :3gears:
    Roger
     
  9. jamyers

    jamyers 2 gallons of fun

    I was wondering if them injuns finally got you! Welcome back, you've been missed around here! :beer :TU:
     
  10. BA

    BA Well-Known Member

    Thanks Roger,

    Now for part two question. Can I use a 3 series case like one from 3:42 or 3:64's to use with my 4:30 gears? Or do I need another style case? :Do No:

    Bill
     
  11. GStage1

    GStage1 Always looking for parts!

    For the 8.5" rears, the 3 series covers 2.73-3.90.
    I know they make a spacer plate for the 2 series carrier to use 3 series gear sets from Jegs for $30. I think your best bet would be to get a 4 series carrier. Many of the Suburbans and full size Blazers have 4.10 gears so you could use the center section and gears from them provided they have the 8.5" rears.
     
  12. BA

    BA Well-Known Member

    Does this hold true for the 8.2 rears also? Planed on using my posi case from the 3.64 rear I have and swapping in the 4:30's.

    Bill
     
  13. GStage1

    GStage1 Always looking for parts!

    I don't have any info on the 8.2" rears since I always swap to 8.5" for cheaper parts and more selection. Wait for Roger to answer that question.
     
  14. oPh

    oPh Well-Known Member

    There are 4 different ratio carriers for the '68-70 Buick 8.2 rears. The 3.23-3.42 ratio carrier should be able to be used with a Mr Gasket 8.2 ring gear spacer & the 4.30's. I'd bet the holes in the spacer will have to be opened up. Always use loctite with correct length ring gear bolts. On the other hand, if the car is 60 footing at 1.90 or better, better to just find the right carrier.

    On 8.5 ring gear spacer uses, I always use 10 hardened washers, one under the head of each ring gear bolt. The washers to use are Mr Gasket SBC hardened head bolt washers ($8 pkg= 34 washers), they will not spread open like typical lockwashers designed for rh thread bolts. Not using these hardened washers on a ring gear spacer equipped 8.5 carrier will result in the LH thread aftermarket ring gear bolts bottoming out & stripping the bottom 2-3 threads on the ring gear bolts :af: Not good at all, both Summit in their 8.5 spacer, & Mr Gasket should provide these small diam hardened washers in the 8.5 spacer kits, but they don't :spank:
    :3gears:
    Roger
     
  15. BA

    BA Well-Known Member

    Roger,

    Thanks for the info. I want to do this the best way and still retain the 8.2,so any idea what the case number/casting number would be for the 4:30 gears and were I can get one? I really don't want to use a spacer. I do have a 3:64 case also. Where is the actual cut-off gear wise when not using a spacer?
    2/3/4 series = gears?


    Thanks,

    Bill
     
  16. oPh

    oPh Well-Known Member

    Bill,
    Hello, '68-70 Buick 8.2 10 bolt carriers are divided into the following "splits":

    High ratio: 2.56
    Mid high ratio: 2.78, 2.93
    Mid ratio: 3.23, 3.42
    Low ratio: 3.64 & lower.

    Have been trying to get the distance figured out on all the "staggers" of the Buick 8.2 carriers for quite some while. This distance is from where the ring gear mates to the carrier flange, to the outside edge of where the passenger side carrier bearing mounts. This is best performed by setting a loose carrier on end on a flat surface & measuring up & down.

    Currently I only have a mid high ratio 8.2 Buick carrier, so will not be of much help there. The main reason I've been trying to figure out the "staggers", is have had folks contact me that were in a pinch to use certain Buick 8.2 4 pinion posi carriers in Pontiac 8.2 rears. One fellow was in Sweden & someone had shipped him the Buick carrier to use in the 8.2 Pontiac rear that he had pulled out of a '71 GP. Ended up solving his problem with an A37 carrier bearing/race combo. Several years before, used a low ratio Pontiac Safe-T-Track carrier in a '70 Buick 8.2 rear. Had to make a thin bushing to take up the "slack" on the carrier bearing boss, so we could press on the (12 bolt style carrier) bearing but this worked.
    :3gears:
    Roger
     
  17. BA

    BA Well-Known Member

    Roger,

    This is exactly what I needed to know :grin: As a side note I also have a poncho carrier(low)and have had a machined bushing to put on it ,however I keep thinking that about the time I do this somebody will be looking for it as a poncho and not a buick. Sure would like to trade it for a buick. I heard that the guts on B&P 8.2 cone style carriers are the same. Is this true or are some different/better?

    Thanks Again,

    Bill
     

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