Would it be better to......
Thread Starter
Race Director
Joined: Dec 2003
Posts: 12,599
Likes: 1
From: Texas
Would it be better to......
I need to have my tranny rebuilt soon, I have the notchy feeling and I think the synchros are going. What would be the better way to go- Should I rebuild the tranny with the Z06 (M12) ratios or should I rebuild my regular MN6 and get gears? I was considering 3.90 or 4.10s but I really would like to keep the price reasonable so I can maybe splurge on some heads 
Advanced
Joined: Mar 2001
Posts: 69
Likes: 0
From: Los Angeles CA
It really depends on what you're looking for. The Z06 will give you roughly the equivalent of a 3.82 (in 1st gear) but you'll keep the final drive ratio in 6th giving you better mileage and less wear and tear at cruising speeds. The 3.90's/4.11's will give you more punch across the board, but at the cost of higher RPM all the time. If it were me, I'd go the Z06 route: get a good launch at the start (0-60 range) and still cruise at 1500 RPM on the freeway.
Good luck!
Good luck!
Safety Car
Joined: Feb 2004
Posts: 4,208
Likes: 2
From: Rochester MN
CI 5-6-7-8 Veteran
St. Jude Donor '04-'05-'06-'07
NCM Ambassador
Racer
Joined: Nov 2002
Posts: 397
Likes: 0
From: Auburn AL
If you still like to drive your car around the street and drive long distances on the interstate I would go with the M12. I had a 2002 Coupe and the cruising ability was great. When I bought my Z06 I noticed better pick-up not only because of the increased HP but the gearing was much different. It still cruises nicely on the interstate but the gearing is a bit lower. At 80mph in my coupe I would be right at 1800rpm and now in my Z I run about 2100rpm at 80mph. With the coupe I would get about 28mpg at 80mph but now with the Z I have to drive 75mph to get that fuel economy.
Thread Starter
Race Director
Joined: Dec 2003
Posts: 12,599
Likes: 1
From: Texas
Actually I gave them a call to ask about a used MN12 and he priced me the rebuild for my MN6 and then to upgrade to the 12 which I thought was a very reasonable amount. I do like the idea of keeping my cruising gears because I have a 25 mile trip one way to work. That said I guess I have my decision
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
80 mph is 1900 in my Z. One of us has a tach or speedo miscalibrated.
Racer
Joined: Nov 2002
Posts: 397
Likes: 0
From: Auburn AL
I am pretty sure it's correct at 2100. I could be wrong but it's been that way since I have owned the car. If you get better than 26mpg at 80mph then yours is probably correct. It makes sense for there to be a significant efficiency drop from 1800rpm to 2100rpm but not from 1800 to 1900rpm. Let me know what you think.
Greg
Greg
Thread Starter
Race Director
Joined: Dec 2003
Posts: 12,599
Likes: 1
From: Texas
Maybe some Z's had the 6th gear different also (just a thought), I was thinking it was .50 on a MN6 to .56 on an MN12. Shouldn't be a big difference in RPMs if the stock gearing is still in place.
I'll do some research on the right numbers.
I'll do some research on the right numbers.
Last edited by vetterlatethannever; Apr 17, 2007 at 01:15 PM.
Thread Starter
Race Director
Joined: Dec 2003
Posts: 12,599
Likes: 1
From: Texas
LS1/MN6 LS6/M12
1st Gear 2.66:1 2.97:1
2nd Gear 1.78:1 2.07:1
3rd Gear 1.30:1 1.43:1
4th Gear 1.00:1 1.00:1
5th Gear 0.74:1 0.84:1
6th Gear 0.50:1 0.56:1
Reverse 2.90:1 3.28:1
Vehicle Speed @ Redline
LS1/MN6 LS6/M12
1st Gear 51 48
2nd Gear 76 69
3rd Gear 104 100
4th Gear 136 143
5th Gear 175 171
6th Gear N/A N/A
Reverse - -
1st Gear 2.66:1 2.97:1
2nd Gear 1.78:1 2.07:1
3rd Gear 1.30:1 1.43:1
4th Gear 1.00:1 1.00:1
5th Gear 0.74:1 0.84:1
6th Gear 0.50:1 0.56:1
Reverse 2.90:1 3.28:1
Vehicle Speed @ Redline
LS1/MN6 LS6/M12
1st Gear 51 48
2nd Gear 76 69
3rd Gear 104 100
4th Gear 136 143
5th Gear 175 171
6th Gear N/A N/A
Reverse - -
