I have a manual c6 putting down 609/609. I was thinking of upgrading to an rpm differential. I know little to nothing about this really. Im running nitrous. What level is good and best gears. Car is never driven daily. Thanks

 

RPM differentials are some of the best in the business. Give them a call and I'm sure they'll be able to recommend a level and a gear ratio suited to your uses.

 

call the MFG? what a concept! your brilliant!

 

And you can't spell. You're*

 

I thought so. I mean after all, other than hp and power adder, we know nothing about his intended use or budget, so if he's going to spend several grand on a differential it might be a good idea to provide that information to the people that do this for a living and get some more info, since he says he knows nothing about this that might be a great place to start while he's waiting for some feedback from the forum.

 

Year makes a huge difference. 05 upgrade will cost you more than and 06 or newer and Z06 is more beefy, but we don't have much to go on here.

What ever you think it will cost, double it and you might be close.

 

nothing in your profile.you can buy a new Z06 differential for around $2,500.thats a reasonable price

 

I assume you mean the "manufacturer" when you refer to "MFG".

Can you please be specific as to which manufacturer you'd suggest he call?

OP I'd suggest you post up why you think you need a new rear end, and you'll get good advice as to what to get based on your intentions with the car. For example, if you're worried about breakage, the advice is one thing. If you are going to drag race all the time, the advice may be different and will depend upon the size of your intended rear slicks. Etc. The more information you provide the better the advice will be.

Welcome to the forum by the way!

 

its an 09, looking for best gear for 1320 duty running et streets 275/40/17. occasionally I street fight the car want to beef up real for durability.

 

z06 diff needs z06 input shaft too. So add a transmission to that price too. Then you are limited to 3.42 gears only if you run the z06 end.

 

For ¼ mile work you want to gear the rear to be at or near redline at the end of the traps in 4th gear.

With 600 rwhp on tap, and short 24.5" tires like you have (which I also have and like very much), I would say that you have the right gear with 3.42. You could go 3.73 but the change is not with the money, coming from experience you'll hardly notice it.

A 600 rwhp car will driven should trap 135 or so which is close enough to redline thus my comment.

Your 09 rear end is very strong. The z06 is slightly stronger with the larger ring gear, but frankly, I would not change your rear to a z06 because it will require you to change the transmission mainshaft as well which is very expensive.

There. We saved you a lot of money!

post script - 4.10 gears make your car feel peppy around town and not on the NOS, they are a blast, it feels like the car lost 500 lbs. That might be worth the money to you. But gears are a fair amount of money no matter which way you go. MPG loss is about 1 combined city/highway, more on pure highway but not a lot. Again, speaking from experience, you can get the same "feel" of 4.10 gears with a COWBooster throttle map or these other throttle remapping devices. No MPG change nor any real performance change from throttle remapping but the car will feel snappier. Again, this comment is based on my personal experience.

 

For your power level and what youre going to be doing with the car I would recommend our Stage 3 build on the differential. As far as the gear ratio that will require a little more information. With 600rwhp and a 26" tall tire I would recommend 3.42 or 3.73 depending on the use of the car. You are more than welcome to give me a call at the shop and I will go over everything with you in more detail.

Thank you,
Jeremy
1-800-406-1109

 

are you open on Saturday. I have been working during regular business hours

 

We are open 8am-5pm monday - friday. What time do you get off work?

 

today 6pm. I normally work 2nd but been getting pulled to first

 

Jeremy is the man. He wont steer you wrong. Always helped me out and sold me only what I needed.

 

Unless your looking for advice on a car, because for some weird reason he likes 3rd gen f-bodies. Ick

 

I got my 3:73 gears fro RPM. Lots of people like 4:10's, but I am very happy with 3:73's.

 

what year did they switch to 30 spline output shaft in manual so that Z06 differential fits?they bolt right into 09 and up auto cars with no mods required

 

Manual Grand Sport has it, as they came with the Z06 diff cooler, starting in 2010 if my memory serves.