Cost to change rear ratio

[JonB]

Please see a very-recent in-depth thread.

PartsRack offers an upgraded gearset, cryo-treated (micro-polished for cooler running and zero whine,) full internals and even new shaft-straps, and a pre-calibrated speedo kit for
"Well under $600" Labor is $300-$400.

Ear to Ear grins IMMEDIATE, and priceless...........

"Best Bang-4Buck Upgrade" after hoses/filters

 

[SamC]

Just did JonB's 3.55 swap yesterday. Unitrax in Anaheim did the work and installed their new light weight half shafts at the same time. The gear swap is worth it and only cost around $1000. The car really moves now. I feel much better with the stronger half shafts and trimmed 12 lbs of rotating mass.

 

[Newport Viper]

SamC,
How long did it take them(Unitrax) to do it? What gear oil did you use? Any install problems?

 

[jimandela]

this is very interesting. Just yesterday I called my Vipertech
about possibly switching the gears. He advised not to. He had never done it. And that seeing that i only drive on the street that it would just require me to shift faster. He said if i really wanted to switch them he would refer me to a shop.??
I said okay. Guess i will stay stock.

 

[JimDavis MT 97GTS 650R]

I finally broke down after 4 years of using the stock 3.07 gears and have ordered some of the new Unitrax 3.33's from Parts Rack for my Venom 650R. Even with the wide open driving out here in Montana, the 3.07's were a little steep. The Parts Rack kit comes complete with ring/pinion, rear end new internals such as shims/seals/pinion bearings,new half shaft and drive shaft loops, and pre-calibrated speedo kit for $614. The gears are cryo treated and micro-polished. I figure about $300 on the install by my Viper tech. The Dana rear end is not rocket science. I'll let you know about the results in a few weeks weather permitting. Thanks Jon B. for the great service!

 

[jimandela]

thanks for the input guys. i will check with the only other vipertech in town.

thanks
JIM

 

[SamC]

Newport Viper:

Unitrax took the whole day but they also changed the half shafts. They put a racing diff fluid with added limited slip fluid to handle the higher temps at the race track. The car ran great right off the lift without any problems.

 

[pauls]

One more time. Buy a spare complete rear. set up new gears in it and keep the original, original. Cost maybe $1200 and you'll have two rears. See classifieds for used rear.

 

[SoCal Craig]

I'm thinking about doing this change also. Where's the best place to go in Orange County?

 

[genXgts]

To the 1/4 mile bandits, whittle me this:

stock car with minor bolt ons allows 1/4 mile to finish off in 3rd gear correct, with stock 3.07's?

moving up to 3.31's, can you still hit the 1/4 in third, or need a shift to 4th already?

I recall reading that with 3.45, or 3.54, it's a must shift to 4th, am I correct here?

Finally, with six so far off, is a 3.73 out of the question???

so many questions, so little time!
Ryan

 

[SamC]

SoCal Craig,

Call JonB at PartRack. He will quote you a great deal and save you the sales tax. He will recommend the installation at Unitrax. They are located in Anaheim. They did a great job on my car.

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by jimandela:
......... Just yesterday I called my Vipertech
about possibly switching the gears. He advised not to. He had never done it....<HR></BLOCKQUOTE>

Heee Heee - ** Hoo! Jim, a prime case of KnoNuthin advise.

Talk to some dealers who HAVE done it, and ask their opinions !


Id be glad to advise...... "No Obligation" to buy! But I can give ya a PILE of references why this is the #1 bang-4-buck street-performance upgrade. {after hoses/filters) CALL ME !

DONT tune your rearend for the last 32 feet of a 1/4 mile drag strip, unless you intend to spend a LOT of time there!

 

[jcaspar1]

Genxgts,
The redline in 3rd is 114 mph with 3.07's so if you want to best that you need to shift to 4th. I know some people don't but I think most people agree it is best to shift into 4th for the quarter mile.

 

[Casey]

Great thread! All this info. is very helpful. My car is in hybernation currently with only tubes/filters as upgrades. I will be ordering headers, exhaust, for installation in the spring(only a couple months away!), and I am waiting to hear about the DIY supercharger kits also. Would like to get in the 600hp range.
Being that I really enjoy the 1/4 mile when I get a chance to get on one. I am looking for the best gear for the street and 1/4 mile, keeping in mind that I would like to go no higher than 4th gear.
Is the stock gear the best above 600hp? 3.33's?

 

[Sean Roe]

Diff clunk and whine, or lack thereof, are results of the diff setup. The differential unit must be properly setup with preload, backlash, heel and toe (accell and decell) pattern. not rocket science (have setup about 50+ Hewland Formula 2000 transaxles in my day). Just takes an experienced shop with the right equipment to do the aluminum case Dana 44's.
There are not that many actual gear manufacturers. I've never seen one that was not properly prepped (as in ground and polished).
I like 3.55's in a stock / minimal mod Viper. On ours, we stayed with the 3.07's.

PS.
If you want a good source to send your complete chunk to for a gear swap, I have one in FL, just south of Daytona. About $500 + shipping (gear set, installation set with new bearings, etc, installed and setup correctly for Vipers).

Sean

 

[onerareviper]

OK Viperholics. I will post these links 'AGAIN'. They educated me on 'gears' and will do the same for you.

P.S. - I have 3.73 gears on a 98 GTS with 450 RWHP. They are perfect, as I can finish the 1/4 mile in fourth at 124 MPH (limit in fourth). With more HP I may have to switch to a lower 'numerical' gear, but 450 RWHP and under I would highly recommend 3.73's. I love it!!!!! Feels faster (buy far), is faster. Never had one problem with noise, overheating, etc...
And I still can get over 20 MPG in 6'th, like I care.

Links:

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

http://www.socalviper.org/techtips/gears.html

Later

 

[Chuck 98 RT/10]

This is another post that pops up periodically. But actual times, 1/4 or lap, are never addressed, it’s always SOTP feel. In fact, all that I’ve read agree that 1/4 times are not improved which leaves lap times. Are they improved? One of these days I’m gonna buy a spare rear, swap the gears and find out for myself. What gear do the Viper Days Wheel to Wheel racers run?

 

[Marv S]

The Viper Days wheel-2-wheel racers have been required to run stock 3.07 ratio for the last year or so. 3 years ago some were running the 3.31 and 3.45 gears but now are all the same at 3.07

The new Comp Coupe has 3.07 gears. EPA, MPG, is not applicable on the Comp Coupe as it's not street legal anyway so that's not the factor in why it comes with 3.07's

 

[SoCal Craig]

Thanks onerareviper. But now I'm even more confused about whether or not a change to 3.55 is worth it. I'm more of a road racing fan rather than drag racing. Mostly, I thought the 3.55 gears would help freeway cruising in 6th while giving a bit more SOP bang when nailing the throttle.

 

[phiebert]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Donald Peterson:
My 94 RT 10 has an annoying clunk in the drive line during normal shifting from first to second and the normal tendency to buck in first at parking lot speeds. The Viper Tech has checked the car and says this is normal for the stock 94 RT 10. Does the lower geared rear end eliminate either of these factory added annoyances?

<HR></BLOCKQUOTE>

Your Viper Tech is wrong. I had my car for a couple years and then it 'developed' the clunk. Turns out it was a slightly twisted U-joint. Once it is twisted even a hair it hits a point of every rotation where it rubs and makes the clunk sound on starting off. Mine was diagnosed when it went from a clunk to a 'bang!' during a street light drag races. I twisted the joint and the bearings in the joint completely. Put on new half shafts with new U-joints and it's perfectly quiet again.

The fact that you mention the bucking at parking lot speeds makes me really believe you have the same problem I did. Bucking is a pain on the early Gen I's and you need to make sure your throttle bodies are sync'd first (see the article on doing that yourself, really easy to do and makes a world of difference). But if your TB are sync'd and it is still bucking it is probably because the wheels are harder to turn at one point then at the others in their rotation because of the twisted shaft or U-joints. You could check this by jacking up the rear and turning the wheels to see if you can feel them getting harder to turn at a certain spot in the rotation.

If you're thinking of getting the 3.55 gears from Jon B, this should solve the problem because you get new shafts with the kit I think. Unless the arms (pardon my terminology) coming out of the diff are twisted (although I guess those are replaced with Jon's kit too).

Anyway, I'd recommend you first sync your TB's to see if that gets rid of the lurching. If I lived a little closer I'd do it for ya, I've done mine a dozen times because I'm anal about it. Once you've done that I think you really want to get the clunk fixed by even trying some new shafts/U-joints. I can tell you it will save you the embarrassment of seeing your back end hang out on the side of the road and watching some miserable Honda whip by you with Type-R stickers on the side when your U-joint bearings give out completely!

 

[phiebert]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by JonB - PartsRack:
DONT tune your rearend for the last 32 feet of a 1/4 mile drag strip, unless you intend to spend a LOT of time there!

<HR></BLOCKQUOTE>

I love that quote Jon.

The only 'real' difference I've ever been able to make in a drag race ET is based on how I do in the first 60 feet. I get into 4th on every race by the end anyway but maybe because I have Nitrous and get power at lower RPMS.

The 3.55 gears intrigue me because it might allow me to have a little more control in the launch. With the stock rear it seems you have so little room between way too much wheel spin and bogging down. If the 3.55 allow me to launch at a little lower RPM under more control without bogging down that should translate into a fraction better on the 60 ft. Which in turn translates into a whole lot in the 1/4.

 

[pauls]

Believe me you'll like 3.55 gears. Much more street snap. Don't know how you can make a Road Racing call on stock gears. Pros gear for every track I have 3.55s and now I use 6th everyday on the expressway at 55 and above, mileage is great on the road.

My suggestion is buy a spare rear and setup the 3.55s. Just bolt the complete spare in. It's easy installation. Then you have the original that doesn't require disassembled and reassembled if you change your mind. Gear costs about $200 at any Dana Spicer dealer, used rear $800, set up locally $300. Only thing left is the install. Easy two hour job. Check classifieds for rear.

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Marv S:
The Viper Days wheel-2-wheel racers have been required to run stock 3.07 ratio for the last year or so. 3 years ago some were running the 3.31 and 3.45 gears but now are all the same at 3.07

The new Comp Coupe has 3.07 gears. EPA, MPG, is not applicable on the Comp Coupe as it's not street legal anyway so that's not the factor in why it comes with 3.07's

<HR></BLOCKQUOTE>

A) The 3.33 and 3.45 were an unfair advantage over stock. Faster down the straights...faster exiting turns. Unfair.

B) The reason the GTS-CC has em is "because they exist already"

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by pauls:
Gear costs about $200 at any Dana Spicer dealer, <HR></BLOCKQUOTE>


IF you buy a $200 gear (my price would be $185) you would not want it in a Viper.

The problem w/ Dana-44 is that so many cheap sets are out there, w/ a 3.55 ratio, but strong enuf for a JEEP w/ 220 ft-lbs.

I can show you a big pile of busted 3.55 cheapies ...... at a well-known vendor but NOT PartsRack !

 

[jimandela]

guys,
it was mentioned to me that i should check out sending the rear
end to unitrax out in CA. It might cost me a bit in shipping
but worth it for less headaches. Seeing that so far, I have to find a local shop for the job

I will keep ya posted as to who ends up swapping them out.

JIM

 

[Greg D]

Question 1: If I were to buy a spare rear diff to "bolt" into my 97, can I buy any year rear diff? Or, are there different diffs for different year Vipers?
Question 2: Anyone out there have a complete rear diff with anything other than 3.07 gears installed that they want to part with?
Thanks in advance.

 

[Sean Roe]

Originally posted by pauls:
Gear costs about $200 at any Dana Spicer dealer,

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by JonB - PartsRack:

IF you buy a $200 gear (my price would be $185) you would not want it in a Viper.

The problem w/ Dana-44 is that so many cheap sets are out there, w/ a 3.55 ratio, but strong enuf for a JEEP w/ 220 ft-lbs.

I can show you a big pile of busted 3.55 cheapies ...... at a well-known vendor but NOT PartsRack !
<HR></BLOCKQUOTE>

Hi Jon,
Can you elaborate a little about this? In this other post dated 01-05-2002 02:32 PM, you say <BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by JonB - PartsRack:, .....PartsRack's gear change kit he purchased included a cryo-treated, polished Dana-Spicer ring/pinion,.....<HR></BLOCKQUOTE> In the post on this thread, quoted above in response to Paul, it sounds like you say the OE brand is not good. Does Dana make 2 different quality of Dana 44 gear sets that fit the Viper? As far as I ever knew, the ring gear is the same diameter on all 44's (which is what allows it to handle the torque), though the steel case units have a slightly smaller pinion shaft and won't directly fit in the aluminum cases of Vettes and Vipers.
What are the differences between the cheap 3.55 Dana Spicer brand 44 gear set and the not cheap 3.55 Dana Spicer 44 gear set? Which Dana Spicer gear sets are piled up at the other vendors? What part of the gear set is breaking (ring gear, pinion, chipped teeth?). Which ratio have you run in your cars?

Sorry for all the questions. I'm just confused by what you wrote.
Thanks in advance,
Sean

P.S.
Paul S,
Did you get the good $200 Dana Spicer gear set, or the cheap $200 Dana Spicer gear set? Do you ever run the 1/4 mile in your Viper with the $200 gear set?

<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 01-25-2002 at 04:14 PM</font>

 

[Marv S]

A diff from a GTS will fit and one from a 1997 and laterRt/10 will fit. Gen 1 rt-10 will require some machining that you don't want to do. Devin at Unitrax just up the coast from you is the guy to talk to

pumpkins with non-stock gears show up on the classifides from time to time

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Greg D:
Question 1: If I were to buy a spare rear diff to "bolt" into my 97, can I buy any year rear diff? Or, are there different diffs for different year Vipers?
Question 2: Anyone out there have a complete rear diff with anything other than 3.07 gears installed that they want to part with?
Thanks in advance.

<HR></BLOCKQUOTE>

 

[pauls]

I've been know to hit the Quarter. 11.05@124. Same gear just a few u joints. Bought it at the local driveshaft shop. D/S dealer.

 

[Greg D]

I thought the Dana 44 in the Viper was actually a super 44 such as the Corvettes and new Jeep Cherokees use.

I am thinking Jon B meant that there are cheap (read low quality) gear sets out there (from questionable manufacturers) that are not equal to the factory/ Dana/Spicer gear set.