To re-gear the diff or not? its 2.73:1

[Marks71BB]

I'm kinda bummed.
I have never driven the car and currently in the middle of a reso (complete).

Opened up the diff and determined its 2.73:1 ratio . I was hoping for a 3.73 or 3.23 I could even live with a 3.08 BUT NOOOOOO its a freeway all the way. I was going to install the eaton posi unit today and found out I have to get bearings specific to the unit.

Well, if I have to order bearings for it, I may as well drop another $175 bucks for new gearing. Question is which to go with?

Its a BB, expecting +- 500 ponies, T400 and top of the line suspension. I am leaning towards the 3.42.

I have N5015 for the rear for now (26-1/2"+-) but will likely change out the wheels in the not too distant future.
I will eventualy run it at the drag strip just for fun but I want to compete on the road course.

Realisticly I will be driving the mountian canyon roads and highways around my home town. Building a canyon carver.
Thanks for any input.
mark

 

[big gear head]

Mark, send me an email and I think I can help you out.

 

[Marks71BB]

OK, I know its a no brainer to put lower gears in it. But which ones? I was wondering if I could get by with changing out the pinion and using the same ring gear I have 41:15 or 2.73:1 could I use a 12 tooth pinion on this ring gear for 3.42:1? Or is the ring gear different?
Obvious I dont know that muchabout differentials.
Mark

Or I gould just go the other extreme and roast em all day with:
http://store.summitracing.com/partd...901322+4294776411+4294776360+115&autoview=sku
Gas and tires would get real expensive real fast....

 

[big gear head]

No, you can't do that. All ring & pinion gear sets are mated at the factory and can not be mixed up. Even if you had two sets of 3.42 gears, you can not mix them. This is especially true if the gear ratios are different.

 

[Marks71BB]

Thats what I figgured.... Hey I just got a pm.
C-ya
M

 

[Marks71BB]

Right on!!!
3.42's on the way
I think I'll save the 2.73 for the salt flat speed record....
Thanks big time Freddie (gear head)!!!
Mark

 

[Silver73]

I recently put a 3.42 with Eaton posi in my car, which replaced an open 2.41, the car is now a dream to drive. With rear tires about your diamiter I am at about 2900rpm cursing along at 60mph.

If you plan to do the work you self, as I did, check out fullsizechevy.com they have an excelent set of instructions on how to do the swap.

 

[Marks71BB]

Thanks Silver73, I do plan on doing the work myself. I will check it out thanks,
Mark

 

[badazz81z28]

3.08 or 3.42 would be my choice. Since you have that much power a 3.73 would have a hard time hooking up on street tires. The Dodge Viper runs a 3.08

 

[Marks71BB]

A 3.73 would wind it up on the highway more than I want, the 3.42 will be the ticket I think..