3.90 Gears
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From: TEWKSBURY MA
3.90 Gears
I have an 04 ZO6 is it worth putting 3.90 in? Does anyone know where to find intructions how to change out complete carrier? Not sure if its somthing I can just do in my garage. Thanks 
Le Mans Master
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From: NJ
Originally Posted by Paul4137
I have an 04 ZO6 is it worth putting 3.90 in? Does anyone know where to find intructions how to change out complete carrier? Not sure if its somthing I can just do in my garage. Thanks
Instructor
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From: Dubai
Originally Posted by robz
It is a nice mod. You may want to consider stickier tires to prevent the excess wheelspin that will occur with the gears. Otherwise you may go slower.
I have them on my 01 Z06 H/C & love'em.Ahmad
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From: S.W. Ohio. . . . . . NRA Life Member
Team Owner
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From: Elmhurst, IL (West Suburb of Chicago) & Home of MEGA Horsepower
St. Jude Donor '06
Originally Posted by Paul4137
I have an 04 ZO6 is it worth putting 3.90 in? Does anyone know where to find intructions how to change out complete carrier? Not sure if its somthing I can just do in my garage. Thanks
I LOVED IT, wheelspin and all!! From a roll it was unbeatable!! 
Le Mans Master
Joined: Nov 2003
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From: Tampa Fl
St. Jude Donor '12-'13-'14
Originally Posted by Mike Mercury
look here (has links to others pages as well):
http://mikemercury.home.att.net/342.htm
http://mikemercury.home.att.net/342.htm
I read your corvette story, and it was beautiful. It made me think of when I became addicted to one. 13 years old at the ice cream store on main street seeing a 63 split window coming down the road hearing it's blower. It had a norrowed rear and fat tires. I was done, a junky
I cant wait to see the battle with my twin 6 year olds who's going to get my car
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Le Mans Master
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From: Atlanta metro Ga.
Originally Posted by PHPD7102
I dont have a Z but Andy at @ A&A told me the 3.73's is the best gear for the MN12 tranny in the Z.
Exactly.. 4.10's (and even 3.90's) are too much gear for an M12.
Team Owner
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Posts: 26,794
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From: Elmhurst, IL (West Suburb of Chicago) & Home of MEGA Horsepower
St. Jude Donor '06
Originally Posted by Dan_the_C5_Man
Exactly.. 4.10's (and even 3.90's) are too much gear for an M12. And 3.73s are not. Trust me, the average stock Z06 with its 3.42 gears and F1 tires don't hook up on the street the way it is, so may as go with the gusto and put in the 4.10s or at least the 3.90s (at a minimum) to get some bang for his buck and make the cost worth it, and to take full advantage of SHEER ACCLERATION from a 2 mph roll to 120 MPH (and the 4.10s will be the winner here) in that race!!
The fastest N/A Z06s in the country with running heads and cam, have run into the 10s in the 1/4 mile, and of course they all had 4.10 gears. Namely the Cartek bunch out east who are hardcore racers and made Cartek's h/c packages famous on their n/a C5 Z06s, 90% of them running 4.10 gears.
Last edited by Mopar Jimmy; Feb 26, 2006 at 05:34 PM.
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Joined: Aug 2002
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From: Austin TX
I have 4.10s in my H/C FRC M6 and would not want to go any lower. In fact, I would rather have 3.90s. With the M12 and a 3.90 rear, wouldn't the first 3 gears be like a 4.38 in an M6? That would be great at the drag strip ,but it's too low for me on a car mainly driven on the street.
I watched my tuner change one out and am surprised that it can be done without a lift. Nice write up Mike.
Brad
I watched my tuner change one out and am surprised that it can be done without a lift. Nice write up Mike.
Brad
Le Mans Master
Joined: Feb 1999
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From: Vilano Beach FL
Howdy!
Good info - I have grand plans for a TT (and possible larger CI motor) for the long-ish term, +but+ I'm thinking in the short term about a H/C setup.
Seems like the setup I'm considering pushes the power curve up a bit, so I'm thinking a 3.90 would really fire it up!
FWIW, I'm thinking: AFR 205's _or_ ETP 215's, GX3 cam on 114LSA, 90mm FAST/TB (supporting components) + the 3.90s -> car is a '03 Z06 (so MN12)
Sorry, just thinking out loud
Good info - I have grand plans for a TT (and possible larger CI motor) for the long-ish term, +but+ I'm thinking in the short term about a H/C setup.
Seems like the setup I'm considering pushes the power curve up a bit, so I'm thinking a 3.90 would really fire it up!
FWIW, I'm thinking: AFR 205's _or_ ETP 215's, GX3 cam on 114LSA, 90mm FAST/TB (supporting components) + the 3.90s -> car is a '03 Z06 (so MN12)
Sorry, just thinking out loud
Burning Brakes
Joined: Apr 2005
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Originally Posted by DT
Howdy!
Good info - I have grand plans for a TT (and possible larger CI motor) for the long-ish term, +but+ I'm thinking in the short term about a H/C setup.
Seems like the setup I'm considering pushes the power curve up a bit, so I'm thinking a 3.90 would really fire it up!
FWIW, I'm thinking: AFR 205's _or_ ETP 215's, GX3 cam on 114LSA, 90mm FAST/TB (supporting components) + the 3.90s -> car is a '03 Z06 (so MN12)
Sorry, just thinking out loud
Good info - I have grand plans for a TT (and possible larger CI motor) for the long-ish term, +but+ I'm thinking in the short term about a H/C setup.
Seems like the setup I'm considering pushes the power curve up a bit, so I'm thinking a 3.90 would really fire it up!
FWIW, I'm thinking: AFR 205's _or_ ETP 215's, GX3 cam on 114LSA, 90mm FAST/TB (supporting components) + the 3.90s -> car is a '03 Z06 (so MN12)
Sorry, just thinking out loud
Team Owner
Joined: Apr 2001
Posts: 26,794
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From: Elmhurst, IL (West Suburb of Chicago) & Home of MEGA Horsepower
St. Jude Donor '06
Originally Posted by DT
Howdy!
Good info - I have grand plans for a TT (and possible larger CI motor) for the long-ish term, +but+ I'm thinking in the short term about a H/C setup.
Seems like the setup I'm considering pushes the power curve up a bit, so I'm thinking a 3.90 would really fire it up!
FWIW, I'm thinking: AFR 205's _or_ ETP 215's, GX3 cam on 114LSA, 90mm FAST/TB (supporting components) + the 3.90s -> car is a '03 Z06 (so MN12)
Sorry, just thinking out loud
Good info - I have grand plans for a TT (and possible larger CI motor) for the long-ish term, +but+ I'm thinking in the short term about a H/C setup.
Seems like the setup I'm considering pushes the power curve up a bit, so I'm thinking a 3.90 would really fire it up!
FWIW, I'm thinking: AFR 205's _or_ ETP 215's, GX3 cam on 114LSA, 90mm FAST/TB (supporting components) + the 3.90s -> car is a '03 Z06 (so MN12)
Sorry, just thinking out loud
AWESOME short term plan you have for that car and it will be wickedly fast for a N/A Z06, especially with the 3.90s!!!
WHen you go f/i or to bigger cubes, etc., you will have to swap out the 3.90 gear most likely for the stock 3.42 with the mega extra power but not a big deal.GO FOR IT!!!!!!
Le Mans Master
Joined: Feb 1999
Posts: 7,121
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From: Vilano Beach FL
Hey Guys!
Thanks for the input/motivation - I think I'm ultimately more of a H/C person at the moment. I still get the sweats thinking of the time and $$$ of doing a FI right (motor, TT kit, rear, fuel, electronics, etc., etc.)
Yeah, I figure if I get the urge to go big and do a TT setup, the costs for swapping the rear won't even be on the radar given the overall expense!
I think the gears + higher RPM power H/C will be FUN! And still reasonably track/DE friendly.
I might ahead and do an upgraded rear while it's being swapped - like a DTE unit that's been blueprinted and HD outshafts. Maybe even a GTE brace since that's only what, like $400 or so? And I'm sure 1000x easier with the rear out of the car.
I think I'm gonna do up the motor a little more too - I have some nice painted pieces, but I think a coil relocation and some nice polished valve covers will really jazz things up.
Take care!
DT
Thanks for the input/motivation - I think I'm ultimately more of a H/C person at the moment. I still get the sweats thinking of the time and $$$ of doing a FI right (motor, TT kit, rear, fuel, electronics, etc., etc.)
Yeah, I figure if I get the urge to go big and do a TT setup, the costs for swapping the rear won't even be on the radar given the overall expense!
I think the gears + higher RPM power H/C will be FUN! And still reasonably track/DE friendly.
I might ahead and do an upgraded rear while it's being swapped - like a DTE unit that's been blueprinted and HD outshafts. Maybe even a GTE brace since that's only what, like $400 or so? And I'm sure 1000x easier with the rear out of the car.
I think I'm gonna do up the motor a little more too - I have some nice painted pieces, but I think a coil relocation and some nice polished valve covers will really jazz things up.
Take care!
DT
Originally Posted by BLOWN ECS Z06
AWESOME short term plan you have for that car and it will be wickedly fast for a N/A Z06, especially with the 3.90s!!! WHen you go f/i or to bigger cubes, etc., you will have to swap out the 3.90 gear most likely for the stock 3.42 with the mega extra power but not a big deal.
GO FOR IT!!!!!!
GO FOR IT!!!!!!
Originally Posted by NeverT00Fast
I have a 03 Z also, and I have the TSP MS3 cam with PRC LS6 heads, Kooks, pulley...etc. With the stock intake mani. putting down about 465rwhp. With a cam size like the MS3 which is just a tad bigger than the G5X3, I find the car hard to drive under 1500rpm. I was going to try to stay with the 3.42s, but now will probably go with either a 3.73 or a 3.90.