im looking to do a complete rear in my car it has stock 2.73. i was looking to do 3.73 with either an aubrun or eaton posi unit Moser 26 or 28 spline axls depending if i use a 7.5 carrier or the 7 5/8 carrier. as of right now i have comp cam part number cs xe256h-10 wih a .447 intake lift and a .454 exhaust. with comp cam spring number 981-16. 1417-16 rocker arm 1.5. 7812-16 pushrods 5/16" flat tappet. edlbrock headers with a full 3' exhaust. fuel press. regulater set at 50p.s.i. the timing is also about 23deg. adv. with the stock gears and a 3" cat back exhaust ran 15.383 at 87.06. and i know for everything to redo the complete rear with out it beng installed is about $1000 and around $600 to have it installed. the car is a tpi. future mod will either be a JEGS High Performance - Blueprint Engines 383ci SB-Chevy 405HP / 440TQ or JEGS High Performance - Blueprint Engines 355ci SB-Chevy 385HP / 405TQ

 

was there a question hid in all that somewhere that i over looked?

 

7-1/2" and 7-5/8" carriers are the same. 7-5/8" came out around 1986. Gears are interchangable on both carriers. In 1990, it was upgraded from 26 to 28 spline axles. You can't put the 28 spline side gears in an older carrier. The axles still won't fit through the end of the carrier.

The only 28 spline factory axles that will fit in a 82-92 third gen housing are from a 1990 - 1992 third gen. Aftermarket 28 spline axles are about $125 each and are better than the factory axles.

Your 2.73 gears are a 2 series. 3.73 gears will be a 3 series however you can buy 3.73 gears designed to fit a 2 series carrier. If you buy a new carrier, make sure you know what series it is to get the proper gears in the same series.

Other than that, I don't know what the question was either.

 

sorry about that im just looking to redo my rear. all new with either an aubrun or eaton posi 26 or 28 spline with Moser axels and richmond 3.73 gears. the rest of post was about what was done on my car. just to find out if the motor would turn the 3.73's with no problem.

 

I'd suggest the Eaton; and ANYTHING BUT the Richmond gears, if this car will EVER be driven on the street.

The Richmonds are single-purpose gears, built exclusively for drag racing. They have a totally different metallurgy (much softer) to absorb the shock of hard launches on slicks with a stout clutch or trans brake. The teeth are also designed differently, for the same reason. If you run those gears on the street, they are almost always noisy because of the tooth shape, and short-lived because the metal isn't intended to stand up to lots of miles. They will fail quickly under the conditions that street gears are made for (high mileage, long life, street tires), just like stock type gears will fail quickly under the usage that the Richmonds are built for (mileage in 1320' increments, a few hundred miles total during their life, sticky tires).

Use US Gear, Precision, Superior, Dana, or Motive gears. Basically, ANYTHING BUT Richmonds, as long as they're a quality domestic brand, and not some made in the Far East knock-off.

I'd also suggest these axles right here, instead of the Mosers. Not that Moser products aren't good; only, that they're made in the way that "custom" axles have to be made, which is, cut to length, splined (cut splines not rolled), drilled, and shipped quickly; they would take an extra couple of weeks if they were heat treated like production axle shafts are. Use these Superior here axles instead: they're heat treated AFTER splining, and the splines are ROLLED, while the metal is soft. Save the "custom" type axles for a "custom" situation where they're the only choice. Price is about the same.

 

so US Gear, Precision, Superior, Dana, or Motive gears would be good for street and strip? and could be used with slicks or drag radials. for when i go to the track