3.55's...

[SRTRICKY]

3.55\'s...

Got a few questions for you boys,
1) How much are they with and without install?
2) Which kind are the best or is there just one company that makes them?
3) How long does it take to install?
4) On a car with absolutely no other mods what type of difference will I feel?
5) Does it void the warrenty is any way?

 

[ARMORGOD]

Re: 3.55\'s...

1. Around $600 (as I recall the install was extra, but had other work done at the same time so couldn't quote a labor figure).
2. Unitrax is very good.
3. Was about a half days worth of work to put them in.
4. It makes an EXCELLENT difference in the drivability of the car. 6th gear can actually be used for cruising at 70+mph now. And the car just has more "pep" on tap.
5. Don't know about the exact impact on warranty.

 

[SRTRICKY]

Re: 3.55\'s...

1. Around $600 (as I recall the install was extra, but had other work done at the same time so couldn't quote a labor figure).
2. Unitrax is very good.
3. Was about a half days worth of work to put them in.
4. It makes an EXCELLENT difference in the drivability of the car. 6th gear can actually be used for cruising at 70+mph now. And the car just has more "pep" on tap.
5. Don't know about the exact impact on warranty.

Thanks...I've heard of people saying "It would feel like you just added 50 horses" true or just a ricer comment lol
Ricky

 

[SnakeEye]

Re: 3.55\'s...

3.55's do wonders for the car...

 

[STUGOTS]

Re: 3.55\'s...

also of people don't get them if they ever plan on going forced because of traction issues and it also limits your stop speed.

 

[DSR207]

Re: 3.55\'s...

Quote:
"also people don't get them if they ever plan on going forced because of traction issues and it also limits your top speed."

Good point, I'm glad I kept my 3.07 .Something to think about RICKY, if you are thinking S/C or turbo in the future...

 

[Andy 98 RT/10]

Re: 3.55\'s...

Yeah, I'd never go with 3.55s. I need all the traction I can get.

 

[MAVERICK]

Re: 3.55\'s...

Basically for a stock SRT rear-wheel torque in first gear is:

450 ft-lb x 2.66 First gear ratio x 3.07 rear end gear = 3670 ft-lb

So, if you swap in a 3.55 rear differential gear, peak torque at the rear wheels in first gear is now:

450 ft-lb x 2.66 x 3.55 = 4249 ft-lb

This is a 16% increase in rear wheel torque without touching the motor. That's the same as keeping the stock gear and modifying the engine to increase its torque output to 598 ft-lb (Take away 13% for driveline losses and you get 520 ft-lb).

520 ft-lb x 2.66 x 3.07 also = 4249 ft-lb

You will gain 16% more "pull" in every gear with a 3.55 gear swap. One of the best "bangs for the buck" you can do to your Viper.

The difference in acceleration is great but as mentioned above by others there are traction limitations, so you will have to run sticky enough tires for the gears. I replaced the Michelins which were breaking loose in 1st/2nd with Kumho V700s and now they really hook.

These links have good straight answers concerning 3.73 swap, for 3.55 just adjust down results:

http://www.viperclub.org/faq/techgears.html

http://socal.viperclub.org/techtips/gears.html

 

[STUGOTS]

Re: 3.55\'s...

Maverick what will it do to the top speed??

I mean with a few bucks on buying better tires the traction issue can be solved but how bad of a top speed loss would we be talking?? because that cant be fixed.

 

[MAVERICK]

Re: 3.55\'s...

Stock 178 mph in 5th gear, but higher if you have a S/C depending on your boost level.

 

[PhoenixGTS]

Re: 3.55\'s...

Maverick what will it do to the top speed??

I mean with a few bucks on buying better tires the traction issue can be solved but how bad of a top speed loss would we be talking?? because that cant be fixed.

Shortening your gearing might even improve your top speed. For example, I have a .64:1 6th gear in my car so once I get the 3.55 gears in 5,200 rpm in 6th will be in the high 170s which is about all you could ever hope for from a bolt on only car with a nice tail wind. [edit] whereas 6th with the stock 3.07 gears puts me way below the max power on the curve and would most assuredly equal a lower top speed.

 

[BigCarrot]

Re: 3.55\'s...

I decided to go with 3.33's in my car. I figured the 3.07 aren't enough, and 3.55's might be too much. Haven't driven it yet, so we'll see!

 

[STUGOTS]

Re: 3.55\'s...

I decided to go with 3.33's in my car. I figured the 3.07 aren't enough, and 3.55's might be too much. Haven't driven it yet, so we'll see!

I'd be interested to see the results

 

[SRTRICKY]

Re: 3.55\'s...

I decided to go with 3.33's in my car. I figured the 3.07 aren't enough, and 3.55's might be too much. Haven't driven it yet, so we'll see!

What other mods do you have?

 

[BigCarrot]

Re: 3.55\'s...

Blower and exhaust. My car makes just under 720 to the wheels.

 

[SRTRICKY]

Re: 3.55\'s...

Nice!! What exaust/header setup do you have? highflow cats or cats removed?

 

[BigCarrot]

Re: 3.55\'s...

Stock manifolds with 3" side exhaust, no cats.

 

[STUGOTS]

Re: 3.55\'s...

Stock manifolds with 3" side exhaust, no cats.

no heads??

1.7 rockers?

 

[BigCarrot]

Re: 3.55\'s...

Nope. And that's with the regular pulley that Paxton sent me.

 

[STUGOTS]

Re: 3.55\'s...

jesus no heads no rockers not even headers with the stock 7.5 Paxton pully made almost 720 at the wheels.


NICE

 

[Viper X]

Re: 3.55\'s...

Something's a bit fishy with those numbers at the wheels. I doubt they are SAE corrected or there may be some AEM or other tuning involved to get there.

 

[DSR207]

Re: 3.55\'s...

RICKY, if you get a chance, check the links provided by MAVERICK, really helpful..

 

[BigCarrot]

Re: 3.55\'s...

Something's a bit fishy with those numbers at the wheels. I doubt they are SAE corrected or there may be some AEM or other tuning involved to get there.

They tuned it... obviously, but they just used the Split Second box. I did a Hennesse y throttle body and bigger injectors too.

 

[ARMORGOD]

Re: 3.55\'s...

Something's a bit fishy with those numbers at the wheels. I doubt they are SAE corrected or there may be some AEM or other tuning involved to get there.

I've seen BC's car (it's at the same tuner that mine is at right now) and know for a fact that it put down 715 at the rear. He has an awesome set-up.

 

[ARMORGOD]

Re: 3.55\'s...

I replaced the Michelins which were breaking loose in 1st/2nd with Kumho V700s and now they really hook.

Maverick,

Do the Kumho's fit your stock rims, or did you change those as well???

 

[Ray R]

Re: 3.55\'s...

1) From a parts perspective, you'll want to make sure you get a complete kit, not just the gears. It will include new bearings, speedo recalibration, etc. $625 at Partsrack. Install can vary from shop to shop. It is CRITICAL that these are set up properly, so use a shop that knows gears and differentials.
2)There are several companies that make them. Get DANA gears.
3)It's typically a 1/2 day job. If you're handy, you can remove the differential yourself and take it to a reputable shop to do the swap. I've seen $200-$400 typical for the swap. But again, make sure the folks doing the work know what they're doing!
4)As said above....best bang for the buck. I've done it on both my Gen IIs. Better acceleration, better drivability, etc.
5)There has been so much discussion on mods and warranties, it seems like it depends on which dealership you bring your car to. In my opinion, it should not void any warranty except maybe for the differential itself. I think I read a previous post where someone stated if the mod does not impact wear and tear on the component in question, the warranty should remain intact. Perhaps you could contact the dealer you'd plan to use for warranty claims and ask.

 

[GR8_ASP]

Re: 3.55\'s...

No speedo recal required on a Gen III. Only required for tires size changes. the Gen III uses the ABS signal to determine vehicle speed and not the transmission output speed.

 

[DSR207]

Re: 3.55\'s...

Quote:
"No speedo recal required on a Gen III. Only required for tires size changes. the Gen III uses the ABS signal to determine vehicle speed and not the transmission output speed."

I had no idea.

It's like going to school, you learn something knew everyday...

 

[SRTRICKY]

Re: 3.55\'s...

Thanks for the links guys, Maverick those links were awesome Now to find a reputable viper tech around here. Anyone know how I can find out?

 

[kaval]

Re: 3.55\'s...

I too am contemplating gear swap... anyone have 3.33's NA and could chime in?