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1969 Firebird 350/350/8.2>>>swapping Chevy 8.2 in, problems

  
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1969 Firebird 350/350/8.2>>>swapping Chevy 8.2 in, problems

 
nuckchorris nuckchorris
New User | Posts: 2 | Joined: 06/14
Posted: 06/03/14
08:45 PM

My 2.93 8.2 was making noise. I figured a 1968 Camaro 3.08 8.2 would bolt right in. The U Joint on my Firebird almost measures four inches across, and the Camaro yoke measures about 3.2 inches across. I learned that I can get a U-Joint that accommodates both. One, I think me and the parts guy can find the right P/N. Is this righton or wrong? Two,I was looking at them side by side since the U-Joint thing took me by surprise. Am I going to need to adjust my drive-shaft length? Three, could I just rattle off the big bolt and swap the yoke from the BOP Rear to the Chevy Rear?
thanks in advance.  

bigD bigD
User | Posts: 151 | Joined: 05/14
Posted: 06/04/14
12:27 AM

The Chevy 8.2 and the Pontiac 8.2 are not the same ! I recommend that you get an 8.5 rear out of a '71-'74 X-body(Nova, Ventura 2, Buick Apollo, Olds Omega). The spring perches are in the correct place for a direct bolt in to your 1st gen. The pinion is much stronger than the 8.2.

You will have to shorten your driveshaft slightly. The guts are the same as those in the 8.5 rears that came in the '71-'81 F-bodies. But the spring perches on the 2nd gen F-bodies are further apart, and must me moved in slightly for the rear to fit into a 1st gen.  Smile

http://www.carcraft.com/techarticles/ccrp_0603_budget_10_bolt/

http://firstgenfirebird.org/forums/ubbthreads.php?ubb=showflat&Number=280248&page=3  

wayne712222 wayne712222
Moderator | Posts: 235 | Joined: 10/13
Posted: 06/04/14
12:26 PM

i personally would prefer the pontiac rear end be repaired...

as the axle bearings retain the axles at the outer end.. where the chevy rear ends are C CLIP TYPE...

can you describe the noise.. is it a rumbling that changes with vehicle speed??? or does it change with power applied and coasting..  if it rumbles with vehicle speed . its probably axle bearings and easily fixed.. by just removing the rear axles and having a machine shop press the old ones off and the new ones on..   warning.. don't hand these to anybody under about 25 or 30... who looks at them strange..  whats this and how do i do that are words to grab axles and run...

if the noise howls. and changes with power settings.. its the pinion bearings that have become comtaminated probably by somebody who used abrasive discs to clean the gasket off the rear end surface.. i would like to strangle those guys.. but they make a LOT of work for everybody..  and is probably the reason they screw it up like that..

rebuilding the pontiac rear end is not that complicated.. its not easy but its not that hard.. it does take some specialized tools and knowledge .. as you have to preset the preload on the pinion bearings by tightening the yoke nut a fraction of a turn at a time. until you reach the proper rotational drag..  like setting front wheel bearings. but you don't want any play at all on these. they run in a preload.. so the bearings are NOT overtightened.. installing pinion nuts with an impact is the death of most pinion bearings..  must use a holding tool and a breaker bar and measure turning torque each fraction of a turn..

the side bearings are also under a preload.. you can set up the lash.. with bearings at exactly zero.. then remove the side shims.. measure them.. swap shim thickness from the assortment that comes with some bearing kits so you increase both shim pack thickness 0.004.. as i recall on one rear end..  this stops the differential from rocking without overloading the bearings with too much crush...


one of a bunch of articles on ring and pinion replacement..
http://www.highperformancepontiac.com/tech/0104hpp_1977_pontiac_ta_axle/viewall.html

i am looking for an article on pressing the axle bearings..  

wayne712222 wayne712222
Moderator | Posts: 235 | Joined: 10/13
Posted: 06/04/14
12:53 PM

getting rid of the C clip axles...

http://www.carcraft.com/techarticles/ccrp_1304_how_to_eliminate_c_clips_for_an_excellent_axle_upgrade/

http://www.carcraft.com/techarticles/ccrp_1012_moser_killer_12_bolt_rearend/


http://www.carcraft.com/howto/ccrp_0801_rear_axle_modifications/viewall.html

pressing on new axle bearings is covered in this article.

http://www.classictrucks.com/tech/1212clt_currie_enterprises_axle_assemblies/viewall.html

this last article is just for fun.. click at your own risk..
model_of_the_month/  

ROWSLEY ROWSLEY
Guru | Posts: 1016 | Joined: 07/11
Posted: 06/04/14
10:28 PM

you can use a 8.5 out of the 70 to 81 f body but you will need to relocate the spring perches to match your 69. the 70 to 81 rearend is 1 inch wider. that is a 1/2 inch on each side. i would check the tire clearance first. it worked on my friends 68 firebird. i going to stick one under my 69 firebird soon.  
76 455/4spd TRANS AM
69 GRAND PRIX 455/5SPD

nuckchorris nuckchorris
New User | Posts: 2 | Joined: 06/14
Posted: 06/04/14
10:58 PM

Thanks for all the replies. 1. Can I get a U-Joint that accommodates a Pontiac driveshaft and Chevy 8.2 yoke? 2. Is the distance from the axle center line to the yoke centerline different between a BOP 8.2 and a Chevy 8.2? 3. Can I just swap the yoke from my 8.2 BOP to my 8.2 Chevy?  

bigD bigD
User | Posts: 151 | Joined: 05/14
Posted: 06/05/14
02:02 AM

Icon Quotenuckchorris:
Thanks for all the replies. 1. Can I get a U-Joint that accommodates a Pontiac driveshaft and Chevy 8.2 yoke? 2. Is the distance from the axle center line to the yoke centerline different between a BOP 8.2 and a Chevy 8.2? 3. Can I just swap the yoke from my 8.2 BOP to my 8.2 Chevy?

http://www.chevelles.com/forums/showthread.php?t=313209

http://www.summitracing.com/parts/mog-253?seid=srese1&gclid=CjkKEQjwqsCcBRDt7_Gts5a91YYBEiQAm-wYEWrN8qhZG4QlczYEgTt4ESEVEKViZJhQAJ8QU0Q-Z0Tw_wcB

There are lots of conversion joints. It seems that I always needed the one that goes from the small 1310 size up to the large 1350 size. You'll have to measure and see what you need on each side.

http://www.driveshaftspecialist.com/HTML%20Measure/UJ%20ID%20Guide.html

http://www.summitracing.com/parts/mog-348/overview/