3.73:1 Rear End Gears for 09 SRT Challenger?

[broadfca]

Hi all, does any one have any experience with 373 rear end gears in an 09 SRT Challenger? It comes with 3.06 gears and I'm thinking of doing a pumpkin swap. These cars wouldn't need a blower for stop light to stop light type racing if they were geared right.

Let's face it. How many of us will ever go 173 mph in these things anyway. My only real complaint with this car is it's good for nothing low end acceleration. If I need to take a road trip, I'll just use my other car, or, spend some extra gas money.

I think it would truly be a neck snapper with the gears and some drag radials.

However, I'm not the sharpest knife in the drawer when it comes to these things, so I would certainly appreciate some feedback from you guys "in the know".

Even though it will cost more, I'd rather be able to just swap out the pumpkins and keep the stock one on hand just in case???? I can quickly and easily do pumpkin swaps myself, so that reduces the cost of a new pumpkin by whatever labor would be to change out the gears. Plus, no chance of a boned up gear change.

I would like to know what the engine rpm would be at 70 mph with these gears. The car is an auto, and right now with the 306 rear end, it runs right about 2100 rpm at 70 mph on the highway.

It might be better if I can find a 355 pumpkin (i don't really know)? I would prefer that it could still be driven on the highway if I wanted too.

It's my understanding that I can adjust for the gears with my Trinity, so we should be ok there.

Any input will be greatly appreciated.

[Mike_Levy]

See if you can find the one for a manual transmission. They come with 3.92 limited slip stock

[mikel]

there are calculators that will let you determine what your cruise rpms will be with any gear...

[pmf1]

I have 3.73 in my SRT Charger. It is easy enough to setup in the predator or trinity. The RPM on the freeway is just about too much. You really can't drive it above 70 without spinning it too hard.

Anyway, 3.73s on the street are too much. 3.55 is a better option with the auto. You will spin like madness on the street. You can't fit enough tire under it to make it hook on the street with 3.73. I also had a 560rwhp 426, so I can't comment on how a stock'ish 6.1 will act. Good luck with whatever you decide

[broadfca]

I have 3.73 in my SRT Charger. It is easy enough to setup in the predator or trinity. The RPM on the freeway is just about too much. You really can't drive it above 70 without spinning it too hard.

Anyway, 3.73s on the street are too much. 3.55 is a better option with the auto. You will spin like madness on the street. You can't fit enough tire under it to make it hook on the street with 3.73. I also had a 560rwhp 426, so I can't comment on how a stock'ish 6.1 will act. Good luck with whatever you decide

I can't thank you enough for this info. I was really close to ordering a 3.73. I will look in to the 3.55s. any suggestions or further info on the 3.55s would be very much appreciated.

Does anyone know if and where I might find a direct swap 3.55 differential for the 09 srt challenger?

[Kahler]

I did the swaping in my 09 RT Challenger. Went from the peg leg to the srt lsd. I do run 11:44@118 and 1:58 60ft. As I have done mods to this point I have went from 13:50s to my PB.
I do use a Edge 4000 stall TC. 1/4 mi runs I use 1st 2nd 3rd and cross at 6000 with the 3:06 gearing.
Hope this helps