342's to 390's What difference. Please respond.
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342's to 390's What difference. Please respond.
In a perfect world, you could have any gear ratio you wanted from the factory.
But seeing as this is a far from perfect world, I need to know what will happen if I was able to swap out my 342's for 390's
How much more will it rev, will traction be much worse on launches, gas consumption right up....etc etc.
Any info???
[Modified by Peach, 4:58 PM 11/19/2001]
But seeing as this is a far from perfect world, I need to know what will happen if I was able to swap out my 342's for 390's
How much more will it rev, will traction be much worse on launches, gas consumption right up....etc etc.
Any info???
[Modified by Peach, 4:58 PM 11/19/2001]
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St. Jude Donor '03-'04
Re: 342's to 390's What difference. Please respond. (Mag Red Monster)
Phil....looks like the mods did some cleaning up of the dupes, but that was the one with my responses......those 3.90s require your carrier and it's been said before that no one outside GM has the proper tools to do a gear/pinion change inside the carriers.....
Intermediate
Joined: Oct 2001
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From: Charleston, Atherton, Great Falls .. SC, CA, VA
Re: 342's to 390's What difference. Please respond. (Mean Green 2000)
There is some vendor selling complete 3.90 rear ends. I saw them the other day, not quite sure where. I believe they were $2200 with programmer....
Melting Slicks
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From: Bethlehem PA
St. Jude Donor '03-'05-'06-'08-'10
Re: 342's to 390's What difference. Please respond. (z06bliss)
Guys, if this is real, then it's good news. Will say this, with 3.73s the difference is more noticeable than I thought it would be. Launching it at the track will be more of a challenge as I can induce wheel hop now where I never had it before. Would imagine 3.90s should make it even more of a challenge. 3.90s will make first gear a real stump puller. Later...
Joe
Joe
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Re: 342's to 390's What difference. Please respond. (Peach)
I would guess you would lose one to two mpg. Remember, programing to correct the spedo. IMHO I dont think 373's are worth it, you would hardly notice the difference. I put 410's in my six speed SS and went from 1800 RPM @ 80 MPH to 2000 RPM @ 80 MPH. Definitely not too much gear. 390's would definitely put a smile on your face.
:D
:D
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Melting Slicks
Joined: Apr 1999
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From: Mokena Illinois
Re: 342's to 390's What difference. Please respond. (oracleguru)
From one of my previous posts:
Going to a 3.73 would give a virtual 2.95 first gear doing away with the pathetic 2.66 gear we are saddled with. The reason why the Z06 has such great acceleration is the 2.97 first gear.
From what I have heard Motive Gear is supposed to come out with a 3.42, 3.73, 3.90, and 4.10 gears for the C5. West Coast Corvette has the dibs on this product but their contract will expire from them in 6 months. The gears from Motive Gear are the ring & pinion type which will be MUCH less expensive than the whole rear section that you must buy.
Motive Gear promises they will just as quiet as the OEMs but your installer MUST be good at installing gears because any misalignment will result in noisy gears (ie howling).
I hope these gears are much less expensive than the whole carrier...
Going to a 3.73 would give a virtual 2.95 first gear doing away with the pathetic 2.66 gear we are saddled with. The reason why the Z06 has such great acceleration is the 2.97 first gear.
From what I have heard Motive Gear is supposed to come out with a 3.42, 3.73, 3.90, and 4.10 gears for the C5. West Coast Corvette has the dibs on this product but their contract will expire from them in 6 months. The gears from Motive Gear are the ring & pinion type which will be MUCH less expensive than the whole rear section that you must buy.
Motive Gear promises they will just as quiet as the OEMs but your installer MUST be good at installing gears because any misalignment will result in noisy gears (ie howling).
I hope these gears are much less expensive than the whole carrier...
Team Owner
Joined: May 2000
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From: Frisco, TX
Re: 342's to 390's What difference. Please respond. (TAL)
I think West Coast Corvettes is supposed to have an announcement about 3.90's just after Thanksgiving, but the cost with core is still much more than the $1,600 GP price currently being put together by LAPD for 3.73s.
As far as just changing gears w/o the whole unit goes, I think it was C5-tech that posted about a month or so ago that it's quite complex and requires special tools. :cheers:
As far as just changing gears w/o the whole unit goes, I think it was C5-tech that posted about a month or so ago that it's quite complex and requires special tools. :cheers:
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From: VENTURA Ca
Re: 342's to 390's What difference. Please respond. (SteveL2)
I don't know what the holdup is with West Coast but i want the 390's real bad! With my cam it will help me a lot at bottom end.
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Re: 342's to 390's What difference. Please respond. (Andy@AandACorvette)
I don't know what the holdup is with West Coast but i want the 390's real bad! With my cam it will help me a lot at bottom end.
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Re: 342's to 390's What difference. Please respond. (TAL)
Wouldn't it be better to swap out with a Z06 tranny than to put a diff in there that will really only help at the strip?
From one of my previous posts:
Going to a 3.73 would give a virtual 2.95 first gear doing away with the pathetic 2.66 gear we are saddled with. The reason why the Z06 has such great acceleration is the 2.97 first gear.
From what I have heard Motive Gear is supposed to come out with a 3.42, 3.73, 3.90, and 4.10 gears for the C5. West Coast Corvette has the dibs on this product but their contract will expire from them in 6 months. The gears from Motive Gear are the ring & pinion type which will be MUCH less expensive than the whole rear section that you must buy.
Motive Gear promises they will just as quiet as the OEMs but your installer MUST be good at installing gears because any misalignment will result in noisy gears (ie howling).
I hope these gears are much less expensive than the whole carrier...
Going to a 3.73 would give a virtual 2.95 first gear doing away with the pathetic 2.66 gear we are saddled with. The reason why the Z06 has such great acceleration is the 2.97 first gear.
From what I have heard Motive Gear is supposed to come out with a 3.42, 3.73, 3.90, and 4.10 gears for the C5. West Coast Corvette has the dibs on this product but their contract will expire from them in 6 months. The gears from Motive Gear are the ring & pinion type which will be MUCH less expensive than the whole rear section that you must buy.
Motive Gear promises they will just as quiet as the OEMs but your installer MUST be good at installing gears because any misalignment will result in noisy gears (ie howling).
I hope these gears are much less expensive than the whole carrier...
Melting Slicks
Joined: Dec 2000
Posts: 2,204
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From: Bethlehem PA
St. Jude Donor '03-'05-'06-'08-'10
Re: 342's to 390's What difference. Please respond. (chrislee2)
Had my 3.73s installed by CARTEK and they seemed to think the changing of the ring and pinion is very labor intensive requiring special tools and the expertise(?)...not the same as installing a R/P in your standard rear end. While the changing of the whole rear has its labor content(3-4hrs.) it is straightforward. Just my 2cents.....
Joe
Joe
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From: Mokena Illinois
Re: 342's to 390's What difference. Please respond. (chrislee2)
The Z06 tranny will cost you more...and you only gain the gearing in the first three gears. 4th gear is 1:1 (given) and 5th and 6th are the same as the MN6.
The 3.73s will effectively change all six gears. You will gain torque multiplication in all gears not just the first three.
The 3.73s will effectively change all six gears. You will gain torque multiplication in all gears not just the first three.
