Top speed concern???
Thread Starter
Too Much Fun
Joined: Sep 2004
Posts: 1,691
Likes: 205
From: Florence, AL
Shifts were fine, I was in OD. Car will pull to 145-146 HARD, but then it's like it just stops pulling. Haven't noticed any tranny problems and I AM EXTREMELY HAPPY with off the line performance, but I just can't believe car stops pulling at 146. With mods and 3.42 gears I would expect this around 160-165, because I understand going from 3.15's to 3.42's I'm gonna give up A LITTLE top end, but almost 30 miles an hour?????
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
Safety Car
Joined: Apr 2004
Posts: 3,996
Likes: 77
From: Louisville KY
I can be wrong, but I believe that the top speed on my 03 mn6 was listed at 176 in 5 gear and the Z06 was 172 (this is due to gearing not engine). I do not remember any numbers in the 180 range.
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
Burning Brakes
Joined: Feb 2006
Posts: 899
Likes: 2
From: Ex BX... Ex NJ... Hello CT!!! CT
This past weekend on a CLOSED TO THE PUBLIC road, I wanted to see what top end was on my car---BOY WAS I SURPRISED....SEE MODS IN SIG Below---I got to 146 MPH and car would go no faster! With my mods and 3.42 gears should this be correct on my 2002 Corvette? I must say I was a little shocked, don't know why, but would have thought top end would be a little faster than this?!?!?!?!?!?! 
If this doesn't seem right, where should I look first (I know my gears would impact it a little---or a lot).....
If this doesn't seem right, where should I look first (I know my gears would impact it a little---or a lot).....Boy I'd be pissed off big time..... I've personally seen my speedo at 168MPH and it was still pulling hard. Think it's time to go back to stock?!?!?
(I think the Z06 rear ducts were slowing you down....)
Last edited by NJ Vette Guy; Feb 27, 2007 at 11:49 AM.
Melting Slicks
Joined: Aug 2005
Posts: 2,995
Likes: 61
From: Fort Wayne IN
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
Gear Ratios M30 4-Speed Automatic MM6 6-Speed Manual M12 6-Speed Manual
Auto MN6 M12
1st 3.06:1 2.66:1 2.97:1
2nd 1.62:1 1.78:1 2.07:1
3rd 1.00:1 1.30:1 1.43:1
4th 0.07:1 1.00:1 1.00:1
5th - 0.74:1 0.84:1
6th - 0.50:1 0.56:1
Final Drive Ratio 1.90 (std) / 2.19 (perf)(6) 1.71 1.92
Z06 has more power, less aerodynamics and a higher RPM cut-off 6700 vs 6200.
Last edited by ajg1915; Feb 27, 2007 at 12:22 PM.
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
They have different final drive ratio's
Gear Ratios M30 4-Speed Automatic MM6 6-Speed Manual M12 6-Speed Manual
Auto MN6 M12
1st 3.06:1 2.66:1 2.97:1
2nd 1.62:1 1.78:1 2.07:1
3rd 1.00:1 1.30:1 1.43:1
4th 0.07:1 1.00:1 1.00:1
5th - 0.74:1 0.84:1
6th - 0.50:1 0.56:1
Final Drive Ratio 1.90 (std) / 2.19 (perf)(6) 1.71 1.92
Z06 has more power, less aerodynamics and a higher RPM cut-off 6700 vs 6200.
Gear Ratios M30 4-Speed Automatic MM6 6-Speed Manual M12 6-Speed Manual
Auto MN6 M12
1st 3.06:1 2.66:1 2.97:1
2nd 1.62:1 1.78:1 2.07:1
3rd 1.00:1 1.30:1 1.43:1
4th 0.07:1 1.00:1 1.00:1
5th - 0.74:1 0.84:1
6th - 0.50:1 0.56:1
Final Drive Ratio 1.90 (std) / 2.19 (perf)(6) 1.71 1.92
Z06 has more power, less aerodynamics and a higher RPM cut-off 6700 vs 6200.
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
Race Director
Joined: Aug 2001
Posts: 11,028
Likes: 5
From: Chicago (Naperville) IL
you definately lose some top end with the gear swap. I had 2.73s and when my baby was stock I remember going 165 and it still could have gone more, but I had to slow down to check my pants.
now with 3.42s, I can't get her past 155
I wonder if there is anyway to regain what is lost in the gear swap
now with 3.42s, I can't get her past 155
I wonder if there is anyway to regain what is lost in the gear swap
Last edited by Humy; Feb 27, 2007 at 12:54 PM.
Thread Starter
Too Much Fun
Joined: Sep 2004
Posts: 1,691
Likes: 205
From: Florence, AL
Not so quick to judge the car.....daily driver that runs 1/4 mile at 11.42 at 122mph!!!!!! On STREET TIRES!!!!!!!
I do a lot more drag strip trips than I do TOP END runs....I can live with it---just concerned!!!
Team Owner
Joined: Aug 2006
Posts: 30,897
Likes: 45
From: Picking on the weakest kid in the yard.
Your fuel pump may be just a little weak or your filter may be partially clogged. A top speed run is the highest fuel volume demand you can do. It is possible to make a 1/4 mile pass with no problems but then have a problem when you hold the pedal down for 20+ seconds. It's worth checking anyway. A laptop in the car could check for lean condition at the time, or a fuel pressure guage would tell you too. Good luck. 
Team Owner
Joined: May 2003
Posts: 23,480
Likes: 9
From: East Meadow NY
St. Jude Donor '12
While the gear change would affect your theoretical top speed.
222mph for an A4 w/3.42 and stock tires vs 277mph for an A4/2.73 and stock tires. The extra hp/tq of the engine (and extra gear) would help you get closer to that number.
I am assuminmg that the 146mph you are getting is in 4th gear, so if you are losing all acceleration at that point, I would check fuel delivery, rev limiters, etc
Last edited by chaase; Feb 27, 2007 at 02:18 PM.