A4 vs. MN6
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From: Maker of Sharp Objects, AL - Roll Tide
St. Jude Donor '10-'11-'12-'13-'14-'15-'16-'17
St. Jude Knife Maker
A lower gear ratio will give you more pull on the bottom end and less speed in the top end. Simply put:
a high rear end gear ratio puts your engine at 1200 RPM at 55 mph.
a medium rear end gear ratio puts your engine at 1800 RPM at 55 mph.
a low rear end gear ratio puts your engine at 2700 RPM at 55 mph.
with a lower geared car, you will get there faster, but the high geared car will pass you in top end.
This is the reason you don't see 1/8th mile drag cars running in the quarter. They just don't have the gear for it. They are built to run up to the 1/8th, but after that its just passing time till they get to the quarter. and Vise Versa, you don't see 1/4th mile cars running in the 1/8th cause the 1/8th mile cars will kick their *ss.
If you go with a lower gear in the rear end it will pull harder and be quicker, but the RPM's will go up at top speed and so will your gas bill....
As far as the difference between the two, I like my manual, but the factory gears in my buddies auto seem to pull harder.
Another friend of mine ran his 5.80 1/8th mile car in the 1/4th for the speedvision show Pass Time, and when he went through the traps he floated the valves because he was beyond redline... Results of running a 1/8th mile car in the 1/4... At least he still ran a 9.60! 
a high rear end gear ratio puts your engine at 1200 RPM at 55 mph.
a medium rear end gear ratio puts your engine at 1800 RPM at 55 mph.
a low rear end gear ratio puts your engine at 2700 RPM at 55 mph.
with a lower geared car, you will get there faster, but the high geared car will pass you in top end.
This is the reason you don't see 1/8th mile drag cars running in the quarter. They just don't have the gear for it. They are built to run up to the 1/8th, but after that its just passing time till they get to the quarter. and Vise Versa, you don't see 1/4th mile cars running in the 1/8th cause the 1/8th mile cars will kick their *ss.
If you go with a lower gear in the rear end it will pull harder and be quicker, but the RPM's will go up at top speed and so will your gas bill....
As far as the difference between the two, I like my manual, but the factory gears in my buddies auto seem to pull harder.
Another friend of mine ran his 5.80 1/8th mile car in the 1/4th for the speedvision show Pass Time, and when he went through the traps he floated the valves because he was beyond redline... Results of running a 1/8th mile car in the 1/4...
At least he still ran a 9.60!
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St. Jude Donor '12 thru '21
X2Most logical answer to this "debate" that I have read here
Le Mans Master
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St. Jude Donor '05-'06
If you want magazine 0-60 times then this is what you'll get.
MN6 - 4.7 sec
A4(3.15) - 4.9
A4(2.73) - 5.1
As you can see the MN6 is generally tested as the fastest. Partly because of the gearing advantage and partly because in the right hands and manual can snick off a quicker more power efficient shift.
However, in the wrong hands a manual can be considerably slower.
MN6 - 4.7 sec
A4(3.15) - 4.9
A4(2.73) - 5.1
As you can see the MN6 is generally tested as the fastest. Partly because of the gearing advantage and partly because in the right hands and manual can snick off a quicker more power efficient shift.
However, in the wrong hands a manual can be considerably slower.
I DO know that with the a-4 and 3:42's you actually have a better gear ratio than a Zo6 through first gear,then it may fall off a bit
Last edited by flynbya2; May 22, 2008 at 09:55 AM.
Drifting
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Both my C5s are automatics with 3.15 gears...My C6 Z06 is a 6 speed of course, with 3.42 gears....If I could have gotten an automatic in my Z06 I would have.....I get VERY tired of shifting......Also, the A4 has a final drive ratio of .7 to 1 if I remember right...whereas the 6 speed has a 5th gear ratio of .7 to 1 and a 6th gear (final drive) ratio of .5 to 1......This causes the engine to "lug" in 6th gear, unless youre doing triple digits (JMO)...Even with 505hp on tap it still "lugs" then engine at normal hwy speeds..At 60 mph in 6th gear Im only revving about 1200 rpm....because of such, I seldom shift out of 5th gear in my Z...I dont like to see rpms below 2000 unless Im idling!!!
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St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16-'17-'18-'19
A good post with alot of good info and grown-up reponses WTF??
As previous advice stated, personal preference and how you plan to use your car is the way to go. I know that the magazine times 0-60 the manual is almost always faster, but if the driver blows a shift those times don't make it to press
As previous advice stated, personal preference and how you plan to use your car is the way to go. I know that the magazine times 0-60 the manual is almost always faster, but if the driver blows a shift those times don't make it to press
Team Owner
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From: Canon City Co
St. Jude Donor '11,'13
"I voluntarily took 60 days off from OT"
A good post with alot of good info and grown-up reponses WTF??
As previous advice stated, personal preference and how you plan to use your car is the way to go. I know that the magazine times 0-60 the manual is almost always faster, but if the driver blows a shift those times don't make it to press
As previous advice stated, personal preference and how you plan to use your car is the way to go. I know that the magazine times 0-60 the manual is almost always faster, but if the driver blows a shift those times don't make it to press
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From: Canon City Co
St. Jude Donor '11,'13
"I voluntarily took 60 days off from OT"
Team Owner
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St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16-'17-'18-'19
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From: Flagstaff Az.
No, it doesn't. In our cars the stock or slightly modified engines cannot pull to their limits with the stock gears. 6 speeds usually can run faster in 5th than in 6th, and an auto with 2:73s cannot pull 6,000 rpms in OD.
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St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16
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Both my C5s are automatics with 3.15 gears...My C6 Z06 is a 6 speed of course, with 3.42 gears....If I could have gotten an automatic in my Z06 I would have.....I get VERY tired of shifting......Also, the A4 has a final drive ratio of .7 to 1 if I remember right...whereas the 6 speed has a 5th gear ratio of .7 to 1 and a 6th gear (final drive) ratio of .5 to 1......This causes the engine to "lug" in 6th gear, unless youre doing triple digits (JMO)...Even with 505hp on tap it still "lugs" then engine at normal hwy speeds..At 60 mph in 6th gear Im only revving about 1200 rpm....because of such, I seldom shift out of 5th gear in my Z...I dont like to see rpms below 2000 unless Im idling!!!
Take engine RPM, divide by transmission gear ratio, then divide by the final drive ratio, and you have the wheel RPM.
Drifting
Joined: May 2005
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From: Littleton Colorado
Don't get too much wrapped up in bench racing. Get the trans best suited to how you drive, or want to drive. If you love to shift and won't be doing high HP drag racing, then MN6 is for you. If you get bored with shifting, then A4 is the way to go. After that, you can modify either to fine tune it to you.
But, if you just want to bench race, its a never ending debate because there are so many variables. LOL...
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From: Canon City Co
St. Jude Donor '11,'13
"I voluntarily took 60 days off from OT"
Not when referring to the transm,ission final drive ratio...Corvette 6 speeds have two overdrive gears...5th and 6th....
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You have to remember the difference between final gear ratio vs. the differential ratio and the gear ratios of the transmission.
You have to multiply the read end ratio by the transmission ratio to get the true gear ratio.
Here are the transmission ratios:
4 Speed Auto (3.15:1 or 2.73:1 axle ratios)
1st, 3.06
2nd, 1.63
3rd, 1
4th, 0.70
6 Speed Manual (3.42:1, axle ratio)
1st, 2.66
2nd, 1.78
3rd, 1.30
4th, 1
5th, 0.74
6th, 0.50
1st gear in a manual would be 2.66 X 3.42= 9.0972:1
1st gear in an automatic would be 8.3538:1 (2.73:1) or 9.639:1 (3.15:1).
So....
4 Speed Auto (2.73:1)
1st, 8.35
2nd, 4.45
3rd, 2.73
4th, 1.91
4 Speed Auto (3.15:1)
1st, 9.64
2nd, 5.13
3rd, 3.15
4th, 2.21
6 Speed Manual (3.42:1, axle ratio)
1st, 9.10
2nd, 6.09
3rd, 4.45
4th, 3.42
5th, 2.53
6th, 1.71
An A4 with 3.42:1 would be:
1st, 10.47
2nd, 5.57
3rd, 3.42
4th, 2.39
http://www.idavette.net/facts/c5specs/index.htm
http://www.chevyhiperformance.com/te...ing/index.html
You have to multiply the read end ratio by the transmission ratio to get the true gear ratio.
Here are the transmission ratios:
4 Speed Auto (3.15:1 or 2.73:1 axle ratios)
1st, 3.06
2nd, 1.63
3rd, 1
4th, 0.70
6 Speed Manual (3.42:1, axle ratio)
1st, 2.66
2nd, 1.78
3rd, 1.30
4th, 1
5th, 0.74
6th, 0.50
1st gear in a manual would be 2.66 X 3.42= 9.0972:1
1st gear in an automatic would be 8.3538:1 (2.73:1) or 9.639:1 (3.15:1).
So....
4 Speed Auto (2.73:1)
1st, 8.35
2nd, 4.45
3rd, 2.73
4th, 1.91
4 Speed Auto (3.15:1)
1st, 9.64
2nd, 5.13
3rd, 3.15
4th, 2.21
6 Speed Manual (3.42:1, axle ratio)
1st, 9.10
2nd, 6.09
3rd, 4.45
4th, 3.42
5th, 2.53
6th, 1.71
An A4 with 3.42:1 would be:
1st, 10.47
2nd, 5.57
3rd, 3.42
4th, 2.39
http://www.idavette.net/facts/c5specs/index.htm
http://www.chevyhiperformance.com/te...ing/index.html
Last edited by 71vetteinva; May 22, 2008 at 05:48 PM.
Thread Starter
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From: 972 and 405
I read that also, but I don't understand how the transmission affects what power the engine makes. I know obviously it will affect how much power makes it to the pavement though.
Why would this thread get locked?
Anywho, I chose the right transmission for me guys, I was just curious about the acceleration times and if they were that much different. Lot's of people ask me about it, so I figured I actually got a car that was much slower due to a different transmission. Thanks for all the technical FACTs. Love those types of responses better than the normal stuff that finds its way into threads sometimes. You guys kick ****!
-Alex
Why would this thread get locked?
Anywho, I chose the right transmission for me guys, I was just curious about the acceleration times and if they were that much different. Lot's of people ask me about it, so I figured I actually got a car that was much slower due to a different transmission. Thanks for all the technical FACTs. Love those types of responses better than the normal stuff that finds its way into threads sometimes. You guys kick ****!
-Alex
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From: Marlton. Increasing performance one speeding ticket at a time! NJ
While technically correct, the A4 has lower gearing in the transmission, so overall 1st gear ratio is approx the same.
2.66x3.42=9.097 (manual)
3.06x2.73=8.354 (2.73 A4)
3.06x3.15=9.639 (3.15 A4)
When you get to 1:1 tranny ratio, the car with the lower gear will still pull harder, but I think as a general rule, you should always consider the overall final drive ratio.
**Edit..........71vetteinva's post was spot on. I should have read the whole thread before posting mine.
Last edited by nj02vette; May 23, 2008 at 03:17 AM.
Race Director
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From: Marlton. Increasing performance one speeding ticket at a time! NJ
Yes they are the same engine and make the same power, just the A4 cars have a lower value of Torque management set in the PCM from the factory. It cuts power if it exceeds this preset value.
Drifting
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