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anyone else have better time 17.3 83mph thats with the 5speed automatic, at 2500ft out here in las vegas..i was hoping for at least a mid 16 to 15.9 pass but didnt work out that way...anyone else have any times yet???? i am curious to see how much of a difference the 5 speed manual is...
 

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Replying to Topic '1/4 miles times'

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Originally posted by twoquickm6


            anyone else have better time 17.3 83mph thats with the 5speed automatic, at 2500ft out here in  las vegas..i was hoping for at least a mid 16 to 15.9 pass but didnt work out that way...anyone else have any times yet???? i am curious to see how much of a difference the 5 speed manual is...[/b]
Is this S or I model? If its S then you should hit 1/4 mile with auto at around 16 seconds but if its I then its right where it should be.
 

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Replying to Topic '1/4 miles times'

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Originally posted by Haris
Is this S or I model? If its S then you should hit 1/4 mile with auto at around 16 seconds but if its I then its right where it should be.[/b]
He's at 2500ft so the run was very clearly altitude affected. A 16.0 car at sea-level is NOT gonna run the same time at 2500ft where the air is thinner and the engine is making less power ;)

http://www.gnttype.org/techarea/misc/altitude.html

2500ft correction factors:
ET: 0.9705
MPH: 1.0311

So a 17.3 @ 83 and 2500ft corrects to:

16.7 @ 85


If that's the 6i 5AT then it's probably a pretty good time. The 6s 5AT should be running a little faster, but you'll see lots of variation from track to track, and depending on the whether also. This correction just adjusts for the altitude, not temp, humidity, pressure, etc.
 

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Replying to Topic '1/4 miles times'

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Originally posted by SteVTEC


            QUOTE
Originally posted by Haris
Is this S or I model? If its S then you should hit 1/4 mile with auto at around 16 seconds but if its I then its right where it should be.[/b]
He's at 2500ft so the run was very clearly altitude affected. A 16.0 car at sea-level is NOT gonna run the same time at 2500ft where the air is thinner and the engine is making less power ;)

http://www.gnttype.org/techarea/misc/altitude.html

2500ft correction factors:
ET: 0.9705
MPH: 1.0311

So a 17.3 @ 83 and 2500ft corrects to:

16.7 @ 85


If that's the 6i 5AT then it's probably a pretty good time. The 6s 5AT should be running a little faster, but you'll see lots of variation from track to track, and depending on the whether also. This correction just adjusts for the altitude, not temp, humidity, pressure, etc.


[/b][/quote]

Doesn't mazda 6 auto has manumatic option too? If so, why not try shifting your own gears and see the difference then.
 

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Replying to Topic '1/4 miles times'

Both of the US engines make their peak power at or near redline. It depends on the shape of the power curves and gear spacing, but the optimal shift points usually end up being about 500rpm past the point of peak power beyond 1st gear. So on engines that don't make peak power until redline, it's tough to take full advantage of the power since you want to center your revs around the peak power point for maximum acceleration. It's tough to center your revs around the point of peak power when the peak power point is right at redline :(

Somebody needs to find out where the rev-limiter is, if nobody has already :D

The optimal shift point, at least on the US engines, is probably a good bit past redline. The 00-01 Maxima guys have the same problem. Peak power isn't until 6400rpm, but the redline is at 6600, and the limiter is at 6700rpm. The engine needs about another 500rpm of revs to play with to really cook.
 

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Replying to Topic '1/4 miles times'

i did use the manual mode with the automatic...you can squeeze almost 1000rpm with the manual mode red line is at 7000 if your quick other wise you'll bouce off the limiter...and i have the 6cylinder...this time is actualy about .5sec faster that the average v6 family sedan here in vegas...so i wasnt to dissapointed the accord runs 17.8 out here....but i am getting ready to do some mods so i'll let you know what they are and the time changes...
 

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Replying to Topic '1/4 miles times'

QUOTE
Originally posted by twoquickm6
i did use the manual mode with the automatic...you can squeeze almost 1000rpm with the manual mode red line is at 7000 if your quick other wise you'll bouce off the limiter...and i have the 6cylinder...[/b]
You mean the redline is at 6300, and the limiter is at 7000, correct?
 
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Reading Topic: 1/4 miles times

i have reved my 6s up to 7200 with out hitting rev limiter....i shifted then it didn't bounce or any thing.. keeped pullin up the that point..nice revin engine.
 

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Replying to Topic '1/4 miles times'

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Originally posted by mazda6s2
i have reved my 6s up to 7200 with out hitting rev limiter....i shifted then it didn't bounce or any thing.. keeped pullin up the that point..nice revin engine.[/b]

hmmmmmmm....


I wonder how accurate the tachometer really is? Does anybody know where the rev-limiter is actually supposed to be set? I smell something fishy....
 

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Replying to Topic '1/4 miles times'

QUOTE
Originally posted by SteVTEC


            QUOTE
Originally posted by mazda6s2
i have reved my 6s up to 7200 with out hitting rev limiter....i shifted then it didn't bounce or any thing.. keeped pullin up the that point..nice revin engine.[/b]

hmmmmmmm....


I wonder how accurate the tachometer really is? Does anybody know where the rev-limiter is actually supposed to be set? I smell something fishy....[/b][/quote]

stock tach is pretty close. when i dyno'd my car we took it to rev limiter and it showed 6750 on paper. 6500 is redline so 6750 actual rpm is rev limiter. just a hair under 7000 is where the stock tach read.. about 6850-6900 on indicated rpm guage. so it's not that far off. i have a pic of the dyno graph if anyone wants to see...so 7200 is quite a far stretch.
 

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Reading Topic: 1/4 miles times

If the limiter is 6750rpm, and mazda6s2 hit 7200rpm, then the tach is "fast" by close to 500rpm. Not cool. Maybe yours is just closer.

Since the torque curve is pretty flat, it's a little tough to do in this car, but you can self-calibrate your tach with your "butt-dyno". The two distinct point in the torque curve is where it picks up at 2700rpm, and then the little peak right at 5000rpm or so. You can check the accuracy of your tach based on those two points, since they're engine related and aren't going to vary much.

For example, we know the engine picks up on the low-end at 2700rpm. We also know there's a little peak, which you should be able to feel, right at around 5000rpm. If according to your tach, those points don't occur until 3300rpm, and 5500rpm, then you know your tach is about 500rpm fast. Adjust shift points accordingly for maximum performance. :D
 
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