Bullet proof rear diff for SRT-10

[Viper X]

Just lost another set of 3.55's tonight. I think it was the Hydraloc again. Left rear wheel locked up at 75 mph again in gear, not even shifting, just a big boom and lots of tire somke. Back to Unitrax next week. I believe I'll go back to 3.07s. Is anybody having success with any diff set up? Comp coupe? Ricardo? Is the quaiffe able to handle 750 rwhp? Am I the only one having regular diff failures?

 

[Kelly06]

I am really curious. Why would you want to run 3.55s with 729 rwhp?

 

[SRTRICKY]

Probably becuase he loves the torque

 

[Viper Specialty]

I am told the Quaife is having no trouble holding up to some Drag guys running upwards of 1200-1300 RWHP. In fact, if half of what I am told about that diff is true, its the way to go. I will be picking one up soon too.

 

[treynor]

> I am really curious. Why would you want to run 3.55s with 729 rwhp?

With a centrifugal blower, real power doesn't show up until 3500-4000 RPM; it's not like Nitrous. 3.55s work really well with the Paxton because they give you a gear which will be in powerband regardless of speed. Also, with drag tires 3.55s make for a much easier launch and are gentler on the clutch/tranny.

 

[NOMERCY]

I am told the Quaife is having no trouble holding up to some Drag guys running upwards of 1200-1300 RWHP. In fact, if half of what I am told about that diff is true, its the way to go. I will be picking one up soon too.

That is what Heffner is putting on my car.

 

[sun diego]

Wow! Locked a rear wheel at 75! Did it spin? Was it in traffic?

 

[BigCarrot]

I almost did a Quaiffe, but I couldn't justify the extra cost. If I break one going 75 I'll probably be able to!

 

[29OUTLAW]

I am told the Quaife is having no trouble holding up to some Drag guys running upwards of 1200-1300 RWHP. In fact, if half of what I am told about that diff is true, its the way to go. I will be picking one up soon too.

That is what Heffner is putting on my car.

How many $$$?

 

[Viper Specialty]

Cost on Quaife is 1895.00, just for the diff. Install will run another 900 or so. It COULD be installed at a local shop for much less. One small modification needs to be done to the axle stubs however, though any competent machine shop should be able to do the work.

 

[Viper X]

Hey Final,

What gear ratio's are available in the Quaife and how do I get one? Any contact info for Quaife?

It seems that I'm going through the hardening on these so called "cryo treated, mirco polished, super duper hardened gear sets". You know, the ones everyone is buying. The claim is a bad batch of gear sets. I've gone through four of these (pre-Paxton) and one Mopar set, the current failure - post Paxton. These more recent gear sets are 3-cut instead of the previous 5-cut gears. The older 5-cuts had much more bearing surface on the gear faces than the newer 3-cuts. I think that the hardening is coming off of the gears and running through the unit. It seems to be wiping out the hydralock and the gear set in previous failures, but I won't know what killed the current set until next week when it comes out again.

Kelly06 -

What Treynor says is exactly correct. The power is linear, though still very strong below 3000 the way I'm set up. Launching can be challenging due to wheel spin, but I'm getting better. I recently added a set of Nitto drag radials, the big 28.7 inchers with just over 12 inches on the ground. These babys really work well. This is the setup that Skip is running with SSR comp wheels and he did a good job putting it together.

With the 3.55's, you go through the traps very strong in fourth gear. On the street, 3.55's are much easier to drive and the strain on the clutch is vastly reduced. This ratio works very well with this car. I just need a diff that will hold up and will probably order the Quaife this week.

Sun diego -

No, didn't spin or hit anything. Just coasted with the wheel locked to the side. This was the second time this has happened to me, so when I heard the boom and saw the smoke from the left rear tire in my rear view mirror, I was pretty certain what had happened. If I'd been in my GTS, the results may have been different. The SRT really handles incredibly well in almost any circumstance and probably saved me a beating.

Dan

 

[Skip White]

This subject has come up so many times in the past. The Q is the way to go, but so expensive. When only one or two shops in the country are doing this, and not enough guys will get together, to create volume purchases, we have to pay dearly. The so called Viper Tax is an issue also. I'd like to take on such a project, but I've already been forever getting on the suspension project, so I won't consider this. As you all know the people at Unitrax are first class, but they have yet to start doing these. Do you guys think we could talk them in to doing them? It going to take a good size group to place orders. Unitrax will make these available to us a much lower price than Taylor, this I'm sure of. Or maybe someone could put up some money, and become distributor for these.

We neeed these in the Viper's that's all there is to it. It's a great setup, not just for it's durability, but for it's driving characteristics. If enough of us go to this setup, the resale of the car will be increased.

Skip White

 

[acrdakota]

Viper X: Man thats some rough stuff locking up a wheel at 75 mph. I would def look into the Q diff as it's nearly indestructable. And be careful man, you don't want to end up like my buddy Chris that put his 360 into the wall going through a tunnel on the 241 (interchange where it goes S towards 5/405.

On a side note where in FR are you? I lived right off Alton/Towne Centre for quite a while.

 

[Daniel Cragin/DC Performance Inc]

We ran an entire formula drift season with a Ricard differential (CC rear end). A very strong unit.

We are cold stabilizing the pinion gears in the hydrolock
now, we will see how these hold up.

 

[NOMERCY]

I am told the Quaife is having no trouble holding up to some Drag guys running upwards of 1200-1300 RWHP. In fact, if half of what I am told about that diff is true, its the way to go. I will be picking one up soon too.

That is what Heffner is putting on my car.

How many $$$?

3K installed.

 

[DSR207]

Quote:
"I am really curious. Why would you want to run 3.55s with 729 rwhp?"
.........................................................
Quote:
With a centrifugal blower, real power doesn't show up until 3500-4000 RPM; it's not like Nitrous. 3.55s work really well with the Paxton because they give you a gear which will be in powerband regardless of speed. Also, with drag tires 3.55s make for a much easier launch and are gentler on the clutch/tranny.
.........................................................

How can it be gentler on the clutch/tranny ?
Do you know of any one having this kind of problems with stock 3.07s ?

 

[sun diego]

Where were you when it happened? Side street, highway?

 

[Skip White]

3.55's would prevail at the track, with an expert driver, but this gear is somewhat anoying on the street, and little use without drag radials. The Viper is just to heavy and geared too high with it's oem gearing to really push you forward, on good pavement, with good tires, so the 3.55 rules in that respect. The car would still bog with 700 plus hp with the 3.07 in it. and it's to ******* the clutch, but as I said, the 3.55 is anoying to drive as it would require very fast shifting and timing when to shift, not to mention modulation of the throttle on take off. 3.55's definetly have some tradoffs, but the car would be a winner at the track, with a good driver, providing he didn't have to shift right before the finish line. When I say good driver, few of us are in that class, unless we spend every weekend at the track practicing.


Skip

 

[Viper X]

Hi Skip,

Yes, the 3.55's work well with the 28.7 inch tall Nittos on the rear. They effectively reduce the overall gear ratio. I'm not a mathemetician, but the shift points at 6000 rpm (my rev limiter is set to 6400) with this setup are as follows: 1-2 = 54 mph, 2-3 = 81 mph, 3-4 = 111 mph, top of 4th is 144 mph. There's plenty of time to shift and the car is pulling very hard in 4th through the traps at about 53 to 5500 rpm, depending on your launch, track conditions, etc.

DSR207 -

Yes, the 3.55s are much easier on the clutch / trans. Simply put, the car is allowed to spin up more ****** with lower gears, reducing stress on the clutch and trans. It's the crumbly hydralock (works great in Jeeps) that keeps failing. I'll be putting a Quaife in as soon as possible.

Skip - I'll be trying to talk Jerry / Devin @ Unitrax into installing the Quaife for me. I'll let you know.

PS - Love those SSR Comp wheels. Man are they light. Thanks for the arm twist.

Dan

 

[Skip White]

Dan the 3.55 with the taller Nittos, is equel to putting in a 3.37 with stock tires, so this doe's compesate a bit, to make the car a bit more fun, and controlable.

I didn't know Devin and his dad were doing the Q for the SRT, because it's not a direct replacement as it is for the GTS. I hope that's so. By the way, I meant to tell you to keep the tire pressure up on the Nitto's, even though they are of good volume, they don't drive very good when low, and they actually still hook up with 31-32 psi in them. I do not like the way they drive with 26 in them, (big, soft sidewalls, narrower, lower speed rating, etc. They really hook to hard, and bring on wheel hop on some roads.

They wear like iron for a drag radial. Have ya noticed the traction factor?

 

[Viper X]

Hi Skip,

Yes, the Nittos offer a bunch more traction than stock. I really liked them but due to the (once again) broken diff, I'm probably going back to the 3.07s until I can have a Quaife installed. Unitrax is working on having the 3.30 / 3.33 ratio available, but it looks like fall. I can't wait that long. I'll probably go to the smaller Nittos (26.4 inch tall Z-rated drag radials that were sized for the Corvette) to get the overall gearing more in line with the taller 3.07 gears.

Unitrax doesn't do the Q yet, but I'm going to try begging. This hydralock is a joke. I also heard a rumor from a good source that DC is acutely aware of the diff shortfall and currently looking for a solution (they're actually considering the all gear Q). Until they get this and many other issues sorted out, I won't be a new coupe buyer, in fact, I just bought an 01 GTS ACR.

Dan

 

[SRTRICKY]

Are there any problems with the hydralock when the car doesn't have s/c type of power?

Ricky

 

[Viper Specialty]

Yes, the Hydraloks have failed on otherwise stock cars on multiple occasions.

 

[SRTRICKY]

Yikes! Even with stock 3.07's?

 

[Viper Specialty]

yes

 

[Viper X]

My first hydralock failure was with headers and k & n's. Same symptoms. 70 mph on the freeway in 6th gear. Loud boom. Left rear tire locked up. Hydralock "locked up" and destroyed the ring, pinion and case.

Dodge stepped up for that one. Not sure about this one yet. I'll let you know.

 

[Daniel Cragin/DC Performance Inc]

The hydrolock reports can be confusing. We just pulled one out of a high mileage SRT with upgrades and some hard use and found it to be perfect. The units that we found that had failed had pinion gears that went through the hardening. Could have been a problem with the manufacturing process. We have heard of failures on the Quaife units pertaining to the different gearsets used.
Rest assured Unitrax will figure out the best combination
(we are giving them some parts to use). Lets all wait and see.

 

[Viper X]

Today's news,

Hydraloc case split, locked up balance of diff, ruined gears, hardened pin, bearings, seals, etc. Case is unbelievably OK (last time it blew a hole in the case). Unitrax will be putting 3.07's, a hardened pin and a new hyrdalock back into my case until I can get a Q built.

Hey Skip,

Looks like Unitrax will install my Q as soon as all the details can be worked out with Craig at Taylor Race Engineering, hopefully before the Nevada Open Road Challenge. I'd hate to have this failure at 165 + mph. Jerry and Devin are very interested in working the details out with Taylor. I'll let you know.

 

[SRTRICKY]

So is Dodge ever going to do a recall??

 

[KenricGTS]

Why did'nt Dodge just use the one from the Gen 2?