Possible Axle swap

[tom]

I have been told of an available original 411 posi 12 bolt for my car. What should I be looking for if/when I get to check it out. I'm not thrilled with the thought of 411's at least not with today's gas prices. If I get the rear what ratios can be swapped. Mine is a 69 base 307 PG with I believe the economy geared rear.

Same person also may have a fold down rear seat, besides the seat itself, what else is needed to convert to the fold down?

Thanks,

Tom

[JohnZ]

4.11's SUCK for anything but cruising around town - you'll see 3900 rpm at 70 mph on the highway. Furthermore, if you buy it and later decide to gear it down to 3.55 or 3.36, you'll have to shell out $400 for a new Series 3 Posi unit, PLUS the cost of the new gears (the 4.11 uses a Series 4 carrier).

[william]

Like John Z said. And why does a 307 'glide need 4.11s?

For the fold down conversion you will need both the backrest and cushion, both complete side panels, latch, floor brackets and the bracketry that retains the cardboard trim panel. Cutting and welding required. If the fold-down does not match the current interior plan on repro covers. The fold-down backrest is notched for the latch so a standard cover will not fit.

[tom]

Don't need or want a 411, but I would like a posi. Just picked up a newer 350 truck block to build, and might stroke it. I am going to swap the glide for an overdrive, just not sure which one yet. I was hoping the 411 carrier could accept a milder set of gears. Reason I ask is It's been offered as trade for a junk benz I need to dump.

I'm more interested in the fold down seat than the 411.

Thank for the help,

Tom

[JohnZ]

3.90 and higher (numerical) ratios require a Series 4 carrier, 3.73 and lower take a Series 3 carrier.

[tom]

John,

Thank you for the assistance. In your opinion, could the 3.90 be acceptable for an occasional use crusier if it had an overdrive tranny like the 700r4 or the 2004r? As best as I can tell there is nothing special about my Camaro, and I do not forsee a perfect restoration in the future.

Might be a dumb idea, but the price is right, and I would like a posi.

Thanks again,

Tom

[JohnZ]

A 3.90 would act like a 2.73-3.08 on the highway in overdrive (depending on the trans).

[tom]

Thanks John!

[arocars]

Get that 12 bolt posi.  They're selling for $1500++  You could always sell it and get something else, like an 8.5 from a nova/ventura that's already rebuilt and has the gears you really want.  Look on ebay for prices and availability.  IMO 3.73's or 3.55's would work really well with an overdrive.   

[dab67]

i agree with getting the rear end for the posi but not for the 4:11. Unless you're racing from light to light with some "youngins". I got a 3:08 in my 67 350 and it is just plain fun out on the highway cruising at around 70 with no real strain on the motor. Stay with the High end gearing.

dab67

[RAfbody]

Richmond and perhaps other gear manufacturers make a 3.73 ring and pinion the is for use on the 4 series carrier.