3.55 Gears Gen2 - Advice

[Boosted Motorsports]

Thanks for the reply. Right now I do have 19" GenV Sidewinder2 wheels. I have the gearing(3.73) in my Trans Am(LS1), but the Viper is a totally different beast. I've thought about FI, but that's a long ways down, I would do a full head/cam package before doing FI on the car.

What's MPG lol, didn't by the car for it's mpg on the highway. I think both the 3.55/3.73 should have relatively close cruising hwy speeds/rpms in 6th, wouldn't they?

I spent a bunch of time as you are now researching the topic to death. I went with 3.73s as I don't plan on ever going FI with this car. I plan to do headwork and stay NA down the road but then get a GEN V as well for my hp fix. The 3.55s most people go with are the "sweet spot" so to speak where it gives a decent increase in accel but also doesn't cause anyone to complain about highway rpm, too short of gear, or loss of traction. 3.73 is for the all out performance if you are staying NA and thats the route I chose to go. I don't plan on driving this car across the country to worry about the rpm sitting high on a big road trip (as this is a factor with some).

I haven't thrown my 3.73 diff in yet as it just arrived last week but I haven't thought twice about my decision after looking at all the factors. As a comparison the GEN V comes with 3.55 stock yet has 200 more hp than the GEN II. Transmission ratios aside that is a hint at what you would chose.

[ViperRyan]

I spent a bunch of time as you are now researching the topic to death. I went with 3.73s as I don't plan on ever going FI with this car. I plan to do headwork and stay NA down the road but then get a GEN V as well for my hp fix. The 3.55s most people go with are the "sweet spot" so to speak where it gives a decent increase in accel but also doesn't cause anyone to complain about highway rpm, too short of gear, or loss of traction. 3.73 is for the all out performance if you are staying NA and thats the route I chose to go. I don't plan on driving this car across the country to worry about the rpm sitting high on a big road trip (as this is a factor with some).

I haven't thrown my 3.73 diff in yet as it just arrived last week but I haven't thought twice about my decision after looking at all the factors. As a comparison the GEN V comes with 3.55 stock yet has 200 more hp than the GEN II. Transmission ratios aside that is a hint at what you would chose.

I greatly appreciate all of your input on this. I am still leaning towards the 3.73 as I want to get the biggest bang for the buck, I love shifting and don't mind doing it more. I don't really plan on FI, but for sure a motor build staying NA. I'm not concerned with RPM on highway, really. I think I read that cruising at 70 in 6th was around 1,800-2k rpms? I still have some time to figure it out as the car is in storage. Leanign towards the 3.73's........

[chicagopd50]

I have 3.73 gears and at 70mph in 6th gear im at 1400 rpms.. but i do have a gen 3 .. i think our trans gears might be different I dont know.. i would totally go with 3.73.....

[venum4u]

I have a 02 GTS H/C with 3.55 gear's. Total blast to drive

[Vprbite]

I think 3.55 is perfect. But I cruised up to Phoenix a lot (120 miles) instead of driving my truck when I had to be up there just cause it was more fun to take the car and we did cruises through Arizona regularly 400mi in a day and I feel like 3.73 would have been too much. Around town and light to light for fun is a different issue of course but still it seems too much to me. On my Gen III, I would only do 3.55s too. I mean, we can bust our tires loose just fine with 3.07s. To me, 3.73s seems like you would be rowing through the gears way too much. I feel there is a reason the 3.55s are so popular.

Obviously, do what makes you happy. That just seems like way too much gear to me.

No matter what ratio you go with, remember you will have to change your fluid a bit more often. More often as you go up. Most of us are on top of our maintenence pretty well anyway, but it's something to keep in mind.

Good luck and enjoy.

[heath1225]

By the way, Dan Cragin confirmed here in another thread, that speedo can be corrected with a tune for Gen 2 Viper. No need for a whatever colored box ;-)

Interested to learn more about this.

[Gavm360]

jrdaly99 - I had my 3.55's installed last fall after owning my gen 2 for ten years - love it - can't recommend enough.

Installed it at the same time as the IPSCO short snifter, car is transformed.

My sense is the 3.73 would be very aggressive but if that is what you're going for then go for it - you definitely will feel the difference over stock

[ViperRyan]

jrdaly99 - I had my 3.55's installed last fall after owning my gen 2 for ten years - love it - can't recommend enough.

Installed it at the same time as the IPSCO short snifter, car is transformed.

My sense is the 3.73 would be very aggressive but if that is what you're going for then go for it - you definitely will feel the difference over stock

Yes, I am still torn on the two. Would love the aggressive 3.73, but the 3.55's also make more sense in the long run I guess. How much did you notice between the 3.07 and 3.55. Does it feel like the 21% / 70+HP guys say it adds?

[GTSgreg]

My 96 with 3.55s is at 1300-1400 rpm doing 60 mph. I feel when playing on an open backroad, I would sometimes leave it in fifth for nicer sound and a little more pull. (Just under 2000 rpm at 60mph in 5th)

[ViperRyan]

My 96 with 3.55s is at 1300-1400 rpm doing 60 mph. I feel when playing on an open backroad, I would sometimes leave it in fifth for nicer sound and a little more pull. (Just under 2000 rpm at 60mph in 5th)

Thanks that helps!!

[GTSgreg]

How much horsepower does the 3.55 gearing claim to add? If my car has high flow Borla cats and exhaust and a KN intake, along with the gearing, anyone know approximately how much Power my car would be making over stock?

[98RedGTS]

Gears don't add power to a car. It just is a multiplication factor in place.

3.07 to 3.55 is about 15% more so the car will feel like it has about 15% more power.

[ViperRyan]

How much horsepower does the 3.55 gearing claim to add? If my car has high flow Borla cats and exhaust and a KN intake, along with the gearing, anyone know approximately how much Power my car would be making over stock?

Gears don't add power to a car. It just is a multiplication factor in place.

3.07 to 3.55 is about 15% more so the car will feel like it has about 15% more power.

I was wondering this as well. Based on my Mods(Intake, Full Belanger exhaust w/no cats), after talking with Dan Cragin and Cory Gehling. They both recommended that 3.55 was the better gear to go with, and they said should see around 21% increase in torq.

[GTSgreg]

Gears don't add power to a car. It just is a multiplication factor in place.

3.07 to 3.55 is about 15% more so the car will feel like it has about 15% more power.

That's what I mean, it's generally making the car torquier and "feel" like more power

[challenger]

I like my 3.73 with 19's in the back and change gear lube every year.

[Boosted Motorsports]

https://driveviper.com/forums/thread...ip-improvement

[Geronimo]

jrdaly99 -

My sense is the 3.73 would be very aggressive but if that is what you're going for then go for it - you definitely will feel the difference over stock

It's not.

[Gavm360]

jrdaly99 - I very much notice the difference of the 3.55 over the 3.07.

You would literally have to be in a coma not to notice. It is a big difference. It is hard to equate it to "horsepower" as it is more of a change in drive ability.

If it helps any I also have intake, belanger headers, cats, corsa catback. I wasn't the owner of the car before that work was done but I'm certain that the 3.55 change makes MORE of a difference than all those mods.

[ViperRyan]

jrdaly99 - I very much notice the difference of the 3.55 over the 3.07.

You would literally have to be in a coma not to notice. It is a big difference. It is hard to equate it to "horsepower" as it is more of a change in drive ability.

If it helps any I also have intake, belanger headers, cats, corsa catback. I wasn't the owner of the car before that work was done but I'm certain that the 3.55 change makes MORE of a difference than all those mods.

Thanks! it does help! I think I am leaning towards the 3.55, as there is so much torq now with the 3.07's and keeps maintenance down over the 3.73. Dan Cragin and Cory Gehling both recommended the 3.55 as well. I also have Heffner intake, full Belanger system w/no cats and some other mods. I am going to have Cory do a full dyno tune of my car and put in the gears.

Really looking forward to getting these in.

[TOTJaybin]

I bought an entire diff used w/ 3.55s off the forums and they howl and whine at low RPMs pretty bad. Think its worth dropping the diff and taking to a shop to see if they can adjust? I have already tried different fluids.

[heath1225]

I bought an entire diff used w/ 3.55s off the forums and they howl and whine at low RPMs pretty bad. Think its worth dropping the diff and taking to a shop to see if they can adjust? I have already tried different fluids.

Did you use the friction modifier?

[Vprbite]

jrdaly99 - I very much notice the difference of the 3.55 over the 3.07.

You would literally have to be in a coma not to notice. It is a big difference. It is hard to equate it to "horsepower" as it is more of a change in drive ability.

If it helps any I also have intake, belanger headers, cats, corsa catback. I wasn't the owner of the car before that work was done but I'm certain that the 3.55 change makes MORE of a difference than all those mods.

Imassume you put horsepower in quotes because you know that gear doesn't add power. It does feel like it does though. I have described it as "dumping the torque on you quicker" and having a resultant feeling that was "snappier."

[Vprbite]

I bought an entire diff used w/ 3.55s off the forums and they howl and whine at low RPMs pretty bad. Think its worth dropping the diff and taking to a shop to see if they can adjust? I have already tried different fluids.

As heath1225 said. Make sure the fluid is correctly modified. After that, they could have been poorly installed or broken in. Of course, fluid is the quickest and easiest thing to check. My 3.55s didn't whine at all

[GTSgreg]

Imassume you put horsepower in quotes because you know that gear doesn't add power. It does feel like it does though. I have described it as "dumping the torque on you quicker" and having a resultant feeling that was "snappier."

Im no mechanic, But by changing the gearing, wouldn't it be somewhat changing the amount of HP going to the back wheels? The crank HP would obviously stay the same but couldn't that affect the wheel hp and torque rating by adjusting gearing?

[plumcrazy]

IIRC, the gear swaps steal rwhp on a dyno