what gears would be best?

[slim]

so I have a 66dodge charger with a 440-4bbl but its not the original engine and I had it rebuilt (bored out and bigger cam), I'm about positive It has a 727 trans. which I recently had it rebuilt too iI think with a 3500 stall It still has the 8 3/4 rear end. I was wondering what would be the best gear to put in I would really like to be of the line fast ( to smoke all these little rice burners ) but I still want to a high top speed. what should i put in.

[andy74]

3.55s with a sure grip,probably be your best bet,as long as you arent running to tall a tire

[phat69charger]

Slim, did you see the reply I posted in the street section?

[andy74]

Slim, did you see the reply I posted in the street section?

i think he posted it in both by accident,but like we both said,3.55s are going to be his best bet

[raull]

Hmm What about a 3.73?

[andy74]

Hmm What about a 3.73?

3.73s would be okay with a taller tire,but with 26-28 inch tall tires i still would go with 3.55s,tolerable rpm on the hiway,and not to much given away from acceleration

[694spdRT]

Do they even make 3.73's for an 8 3/4 rear? Summit's catalog doesn't list any for either the 742 or 489 case.

[phat69charger]

694spdRT they make 3.73 check this link out  http://www.autohobbydigest.com/8_75.html  down at the bottom of the page.

[694spdRT]

694spdRT they make 3.73 check this link out  http://www.autohobbydigest.com/8_75.html  down at the bottom of the page.

Thanks for the link but, who offers the 3.73 gear now? That ratio might work well for me in the Challenger with the 833OD.

[69fuchs]

ty, you could check with doctor diff (Cass Eslick) on moparts, or randy's ring and pinion.

[74Charger]

694spdRT they make 3.73 check this link out  http://www.autohobbydigest.com/8_75.html  down at the bottom of the page.

Thanks for the link but, who offers the 3.73 gear now? That ratio might work well for me in the Challenger with the 833OD.

Here try Strange Engineering  http://www.strangeengineering.net/catalog/index.html or http://moserengineering.com/Pages/Ring-Pinion/ringpin.html
Looks like they are only available for the 489 case.
I just bought a set of 3:91's for my 742 case from Strange. They were the two cheapest I could find.  And they were very helpful.

[Ghoste]

Randy's offer a 3:73 for a 742 case.

[slim]

I don't know I have some decent sized tires (not sure what size but I'll find out tonight) I was thinking about putting in a 5.13

[phat69charger]

Slim, here's a link to a calculator to use to figure out your RPM's and MPH with your information from what you have in your car:

http://users.erols.com/dmapes/GEARCLC.HTM

[Ghoste]

Wow, that is a pretty serious gear for a street car.  Are you sure you want that?

[BLAM]

5.13s!  Guess highway driving would be out and hope that the car revs to 7500!

[tan top]

I would go with 3:55

[deputycrawford]

I might be getting too technical but what cam is in it?  what is the compression, intake ETC? Over simplifying it might suggest a 3.55. Even a 3.23 sounds a bit high reving for a person that uses overdrive everyday. That 3.55 would be the best for both worlds. I would still like to know the rest of the engine combo.