Rick Z-06

I am finally having some work done on my 2007 Z-06. I知 having the head issue squared away with new heads and I知 having a mild cam, new headers and an exhaust cut-out switch installed. I知 also having a new intake installed and all the bolts, fasteners, plumbing lines, and gaskets upgraded. My question is this, what rear end do I want to put it the car? Mind you it will never see a drapstrip nor racetrack, however most miles I put on it will be highway or driving around the Lake where I live to and from corvette shows. I知 thinking 3.73 or 3.90 as 3.55 isn稚 that much different than the stock 3.42痴 and 4.10 is too extreme. It already has a close ratio shifter with a ball on it. Any suggestions would be greatly appreciated! Also what does every think about LMR doing the work? I realize that they are expensive but I want it done correctly and if anyone knows a better or more inexpensive option I would gladly entertain that. Rat痴! I guess also, thoughts on a supercharger over a cam and emissions testing. Thank you all.

Pb82 Ronin

3.90's and 4.10's are your ONLY option for the rear end unless you upgrade to a race unit which is in the $8-10K range.

furious427

For the driving you say your gonna be doing leave the stock gears.

grinder11

All I'll add is this; the guys I've talked to say that the 3.90 diff makes 5th and 6th gear more useful, without really subtracting anything from drivability or fuel mileage. But it's not cheap. I kinda agree with keeping stock gears. If you will never see a strip or HPDE, there's really not much point in it. My .02....

Last 1

My 2 cents as far as I’m concerned a 3.90s gear is the best mod u can do.(the best money I spent)That if you’re staying HCI and staying NA.

jayyyw

If you have any plans to go supercharged later on, stick with the stock gear. 3.90 if staying NA.

449er

Welcome to the forum! For your type of driving, I would stay with the stock gears

romandian

with 3.9 in the rear you will spin in first. shorter 5./6. is a better idea.

Pb82 Ronin

You know of a ZO6 that DOESN'T spin in first?

92rsz

Mine would hook if you rolled into the throttle and didn't floor it til after 4k. Now that it's H/C/I no chance. I would do a 3.90 if you're going to run a sticky tire at all times. If not I'd leave the stock gearing. A cammed ls7 can get out of shape in a hurry even with the stock gear on street tires

grinder11

LOL-If anyone does know of one that doesn't spin in first, a dropped valve has just happened, or is sure to happen-SOON!! But I think he was trying to say first gear will be almost useless w/o DRs or slicks!!

Mike44665

I have had the 4.10's since early 2018 and it is the best mod for driving the Z, IMO. It still gets mileage way over 20 mpg, third gear is a blast, and you can now use all six gears when doing cruising on the back country roads. It was big bucks at the time, but I sure enjoy it. I don't even try, but if the shifter was bolted right to the trany like my old Z/28 was I'd be back to the original no lift shift. Honestly it really makes driving it a lot more fun. BTW the 3.90's throw the speedometer off, a fixable issue. The 4.10's ring gear is the same number of teeth as stock so no issues arise.

RobGOV-DCZ

There is no better seat of your pants bang for the buck mod than 3.90's

Do it

herwawan

Good info - how do you fix the speedometer issue?

REDSEE5

I致e been thinking about 3.90 gears for a few months now, but curious to hear a rough estimate on what people have paid for the swap (labor.) Anyone aware of the average cost for install?