[shclayto]

I have a 67 camaro with a 4-speed Muncie and 10 bolt rear end. The car came with an automatic and has stock gears (2.73s I believe). I want to replace the stock rear end with 3.42, 3.55, or 3.72 gears.

I have 3 questions:

1) Which rear gear is best for street/highway use (no to little dragging) but still have some grunt up front and through all gears?

2) How do I know which gear set to buy for replacement (8.2 or 8.5")?

3) Is a posi rear end worth the money and if so, where is the cheapest place to buy say Eaton posi?

Thanks.

[Jeff L88]

It sounds like you want your cake and eat it too! I would suggest a 3:73 gear ratio for all around driveability and rompity-romping. As for the what size carrier you have it should be an 8.5" if it is the originally rear end. When it comes to posi units, there is an old saying that goes; you get what you pay for! The only one I would shy away from is the powertrax, I have installed these units and seen these literally strip the square ends off the cog gears resulting in garbage. If you are running 375 horse or so you can get by with a stock 10 bolt posi unit. I think a fair price would be about $75-125., Tear it apart and shim up the side gears and you should be set.

[1969NovaSS]

If its the original rearend and its a 10 bolt its a 8.2.also if its an original 2.73 you have to change the to a 3 series carrier but since your upgrading to a posi i done see any problem.eaton posis are expensive but you could get an auburn for 360 on jegs or a powertrax locker for 420.if you are going to build decent power its nice to hace "c" clip eliminators, just in case, you can get some for around 150.

[Jeff L88]

Sorry, I was thinking about second generation carrier. Jeff

[shclayto]

I did some research and found that I have an 8.2" 2.73 rear end. I want to replace them with 3.55. Most 1st gen. camaro sites have the pinion listed as 28-spline. However, all aftermarket catalogs (Summit and JEGS) have 27 and (more commonly) 25 spline. What is the deal here?

Also, what are "c" clip eliminators?

[jimfulco]

They may be referring to different spline locations (pinion gear shaft splines or axle shaft splines). GM used two types of 8.2" axles back in that era. The Chevy-type unit had the 25-spline pinion shaft, while the Pontiac-type pinion had 27 splines. Both types used axles with 28-splines.

[1969NovaSS]

"c" clip eliminators are pressed on to your axle and bolt to a backing plat behind your drum. c clips are a tiny clip about an inch big that hold your axles in place.if you ever snap an axle with the c clips your wheel just falls off and you go no where. with the eliminators you can still push your car of to the side.