Asbussey

Hello I'm on the fence about gearing my 455. Im gonna upgrade the transmission but right now I'm looking at complete rear end packages. Moser offers complete rears with 3.73 and 3.42. Does anybody have either if the two setups? If so id like to know how the ride is. Thanks in advance.

Fun71

What rear tires do you have? The tire diameter works with the rear gears to determine the overall effective gear ratio and engine RPM for a given speed.

joe_padavano

What is your planned transmission "upgrade"? What is your rear tire diameter (not wheel diameter)? How do you plan to use the car?

People lose a lot of sleep over this, worrying about using steep gears on a car that only gets occasional weekend use. Personally, I'd always chose the steeper gears, since I want the performance. If your trans upgrade involves an overdrive, this is a no-brainer. Get the 3.73s or even 3.91s. If you plan occasional track use, get the steeper gears. If you only plan to drive to the weekend cruise night and back, get the steeper gears.

sschevellecutlass_Bob

Up front I would say if you are contemplating 3.42 it is for good reason, so I would go with it. I went through the 4.10 and 3.73 for my Chevelle and went with 4.10. It was too high........In addition to the points above, I would definitely include the 1st gear ratio of the new tranny. If first gear is high, then you don't want to go too high with the rear gear. Also, determine just what you are gaining and losing between 3.73 and 3.42. Are you a serious racer chasing half seconds or just wanting to feel power when accelerating? Will you feel a big difference between the two? I don't think so. Do you race with the Street Outlaws or other cars on the road or just exercise your horsepower on clear roads once in a while? It's all relative, so if you don't go up against someone else, what difference does it make? I don't think you get much of a difference except in the highway driving aspect, so that is why I recommend you go with the 3.42. It will give you more versatility. With my Chevelle, I am taching 2800 at 70 with my 4.10, TH400 and Gear Vendor and the 497 (295/295 Cam) and it hums nicely along. The 295/55/50 tires help a lot over the 295/50s, so like above, tire size helps too. I also went with 4.10 using a 3 series carrier in case I wanted to go back to the 3 series gears. It's similar to converter decision..... if you go with a higher stall converter, putting around town becomes a potential heat problem - you lose versatility. The bottom line is what is your intention for the car? Cruising the downtown circle and challenging all cars for race - like American Graffiti (great movie - showing my age).... or cruising the highway looking for high speed challenges......? These days after completing a total frame off restoration, the last thing I want to do is spin out into the median or into the dam bayou, so the rear gear matters even less. Oh, I still plan to put the 325/50s on the back once in a while, but what difference will it make to the gators around whether I have 4.10, 3.73, or 3.31....? I think you can have as much fun and enjoy the car with any of the three. When I stand around at the car club meeting with the car parked and the hood up, and tell people I have 4.10 what does it matter? I do feel I learned a lot by choosing the 4.10 and I racked my brain about it....... so, that's why I through this rambling response together for you.... have fun and don't worry about decimals too much...... Check the 1st gear of the tranny, your tire size, and your highway, town driving (or racing) requirement. Guess I could have just posted that one sentence!!!!!



Oh, if you can cruise with someone who has the different gears, it would help...... not sure if you have that luxury..... I wish I had tried..

I do remember one pickup I had with a 3.31 was a total dog compared to the other ones with 3.73 rear........ not sure if the 3.42 is dog like....

I have a 3.31 rear gear in my garage that I may install one day....... just to see what the difference is.......

Fun71

As you said, this all depends upon what you want from the vehicle. A friend of mine has 4.56 rear gears and a TH700-R4 transmission with a 3.07:1 1st gear ratio in his Vette and he absolutely loves it.

sschevellecutlass_Bob

Fun71 - that's radical and awesome! I can feel the neck snapping back on take off with that combination!!

Battenheaded67

RetroRanger

Put me in the other camp, I had 2:7x rear gears swapped to 3:42 w ~27" rear tires. At 70 ish mph I'm turning 3200 rpms. Dave is quick to point out the car will run this all day, it's true it will, but the added noise decreases comfort and conversation.

It all depends on intended use I just like cruising around and getting on it, don't race or take it to the track. If I was racing I would like the 3:42 or taller better.

With a BBO lighting up the tires to sliding it around doesn't take much w either gear

OldsAl

I run 3.73's in my 72 W-30 convertible and my 70 W-31 bench 4 speed car has 3.91's in it. I also have 4.10's in my A12 69.5 440 6 pack Superbee. So Im probably the wrong person for input but I love all my cars the way they are set up. I had 3.42's in the past and while they are good overall the 3.73's are more fun. My W-31 is a factory TO (3.91) rear end car but the previous owner switched to 3.42's which with a 350 were ok but the motor is way happier with the 3.91's and so am I. :-)