knock, knock....I need a rearend guru

ok....I know when it comes to rearends the discussion can endlessly go on. From some research on my part the rearend on my 64 longroof is a 10-bolt 8.2 setup and I think the stock ring & pinion is 3.36?? What advantages if any if I were to change the gear ratio to 3.55 or even 3.73 and still be able to hold down any whining down the highway. Or would I want to change the 3.36 gear ratio even if I'm running a high perf engine. Also, what if any horror stories are there about the c clip axles that are common to chevy rearends. A friend told me that moser engineering has an alternative answer with their c clip eliminators. I'm on a limited budget is why I can't upgrade to a complete new rearend setup.....the only upgrade I'm considering is an eaton posi and new axles to replace the originals.

Fire away guys, my radar is on!!!


Thanks..........

I'm definitely no guru......but what exactly are you wanting? A 3.55 or 3.73 compared to the 3.36 will give you better acceleration, however you will be revving higher which will of course decrease your fuel economy.

Upgrading to a posi unit and new gears will probably run you $1000 or so. You can have the best of both worlds by putting a 200R4 or 700R4 overdrive transmision and a new set of gears with your posi unit. Plenty of guys here have stock 8.2's and abuse them somewhat with no detrimental effects.

I have a 700R4 in my 63 and have 3.73's (205-60-15 tires) and run at about 2000 or 2100 at 60mph. With a T350 in my car and 3.55's, I was running at 3000 rpm at 60mph. I didn't like that, especially for longer highway runs which I avoided.

Hey Now. The Eaton posi unit, with the right gear ratios will do what you want to do.(3:36 to 3:73's) The whinning should not be heard. The whine is caused by the gear mesh not being correct. Get the backlash, pinion depth, coast and accelerate set right with the correct shims and it will be quiet. Also as suggested get an overdrive trans will help for fuel milage. 2004r is good with gear ratios that keep you in the power band of your engine. Hopefully, Jiblomate will jump in on this thread or you can pm him. Respectfully, "Bill's" II

Don't worry about the C-clips if it's a driver. C-clip eliminators secure the axle better but many of them leak.

Dan (not a rear end guru, but I did stay at a Holiday Inn last night.)

3.36:1 is a pretty-nice set-up for a street/strip car with small diameter tires. It was the high-performance rear gear ratio from the factory in 1964.

Best of both worlds.

That rear end of your's will take some abuse. I used to beat the crap out of mine in my 64 SS 4-speed.

Great input, guys....wellll as we all know we all have the "Tim Allen" personality as our alter ego to a certain extent. With that said, I want the best of both worlds...good acceleration from a standing start along with decent highway driving. Guess I'll stay with my current gear ratio yet trash the open carrier for the eaton posi, new axles...and no c clip eliminators. Now all I have to do is decide on the tranny! Decisions, decisions....next I'll resolve our economic recession!!!


Thanks, guys.....!

We went from 3.08 pegleg and 27" tires and turbo 350 to 3.73 posi 700r4 and 26" tires. It feels like we picked up 50hp and have lower rpm's on the hwy then we had before. The extra low 1st gear on the 700r4 is like haveing 4.10 rear gears!:yes:

Great input, guys....wellll as we all know we all have the "Tim Allen" personality as our alter ego to a certain extent. With that said, I want the best of both worlds...good acceleration from a standing start along with decent highway driving. Guess I'll stay with my current gear ratio yet trash the open carrier for the eaton posi, new axles...and no c clip eliminators. Now all I have to do is decide on the tranny! Decisions, decisions....next I'll resolve our economic recession!!!


Thanks, guys.....!

My horror story with the c-clip is this. My center pin busted somehow and allowed the c-clip to fall off the end of the axle. As I was heading home after some grudge racing at the local drag strip my axle started to walk right out of the rear end luckily I was just leaving and not going very fast. A couple craftsmen sockets and some mechanics wire and we were back in business for some light duty traveling.

Now if I was going to be buying new axles I would be getting them with the c-clip eliminator with out a doubt, not that the c-clips won't work but if I'm buying new I'm gonna upgrade. As for the gear ratio the 3:36 sounds like a winner. The new center section will offer you some really good strength to your 8.2. With a good center section I used to run 4:88's. The carrier and gears lasted longer than the welds on the axle tubes holding the leaf spring perches.

my 70 nova I had 2.56's with 245/60-15's would cruise on the freeway excellently!!!! like 80mph under 3,000. No guts on the streeet though.

I switched to a 3.42 posi, now on the street its killer, but revved alittle bit on the freeway. Didn't like it on the trip to HAN.