Shifting points?

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sl0wthe0ry

pfft....MS3?
:
Mazda 3s
I'm takin my 3 to the track to see what i can run before i start teh mods. what are your guys' shift points. i dont want to learn the hard way on this one. i hada sentra before this car, i knew how to drive it perfectly, this cars a little dif, like +50hp @ the crank difference lol. thx for the posts
 
Are you talking drag strip? Shifting between 6500 and 6800 should get you to the finish line just at redline in 3rd gear. You don't want to get much past that because the rev limiter kicks in at like 7200.
 
(braindead yeah im talkin drag. i raced the other night w/ a broken motor mount, sadly :(. gettin that fixed tomorrow. but i ran a 16.9 on 91 octane? wtf? i had a .281 r/t tho
 
without better mapping won't a higher octane have no affect on our cars????
 
Actually

If you look into the dyno tests that are ran on our car you will notice that our power decreases after 6K RPM. That is where our peak power is at. So taking it to redline you actually begin to lose power before you hit it. Your optimal shift point would be right @ 6000K if not right before, which is what the article that djltoronto posted was trying to get at.
 
if u take it to redline, then when u shift, the rpm is closer to 6k, it's a trade off, faster first gear, or more power on second
 
Curious if anyone uses "speedshifting" (I believe it is the correct term for it). Basically your foot never leaves the gas, while accelerating you QUICKLY put the clutch in, shift, and let out. Anyone notice if it shaves much time off if any. Its not really that bad for the vehicle, as long as you dont do it all the time. Also power shifting, as in shifting w/o using the clutch. Its hard to do because you have to know what rpms to put it in gear at, I dont really see much advantage in this but some people do it for whatever reason.....
 
speed shifting is dangerous when u r too close to redline, plus u can't speed shift 1st to 2nd on proteges, don't know y
 
Armyguy1104 said:
Curious if anyone uses "speedshifting" (I believe it is the correct term for it). Basically your foot never leaves the gas, while accelerating you QUICKLY put the clutch in, shift, and let out. Anyone notice if it shaves much time off if any. Its not really that bad for the vehicle, as long as you dont do it all the time. Also power shifting, as in shifting w/o using the clutch. Its hard to do because you have to know what rpms to put it in gear at, I dont really see much advantage in this but some people do it for whatever reason.....
Click to expand...


Power Shifting is NOT shifting with out the clutch. Power shifting and "speedshifting" are synonymous.

The dangers of powershifting are two fold: one, you risk over reving the engine, and two, damage to the transmission.

For the first risk, the Mazda3 (and most all modern FI cars) have a rev limiter to prevent you from over-reving.

The second risk is real. Powershifting is murder on sychronizers. After time, you will wear off the teeth on the sychronizers and then all of a sudden, you cant shift into that gear anymore. Its an at your own risk type of thing. I don't think warrenty would cover that kind of obvious abuse. Since I don't know too much about the Mazda trannys, I wouldn't do it. On my camaro, however, thats another story. (drive)
 

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mobomelter said:
hey if your synchronizers go you can always double-clutch.
Click to expand...

Yeah, if you like to drive your car like its a truck. ;) Not good for racing, but will get you from A to B.
 
So what was the answer to the question to shift at 6k, and I have a question on take off on what rpm should you rev the engine? I usually rev it to 3k, but some of my friends said thats too much???
 
This may prove useful for you guys.

Basically, it's a simple excel sheet that calculates vehicle speed from RPM's in any given gear.

Most useful to note what your RPM's will be in the next gear, say your shifting from 2nd to third at 5000 RPM's in second, you will be at 3556 RPM's when you get into 3rd..

Unfortunately this does not tell you the best shift points since it does not include the a torque curve for each gear!! But I would suggest that if you are trying to go as fast as possible, it's likely that shifting from first to second at redline is the best, only because of where you will begin second gear. Shifting from 1st to 2nd at 7000 RPM's brings you down to 3899 RPM's in second... that's pretty low and there's not much we can do about that. (Having a close ratio six speed would have improved this)

You can change any of the numbers that are RED, the rest of the numbers are calculated automatically! (wow) (rockon) (drive)

Enjoy

(attn) I believe all of these numbers to be accurate; all the gear ratios came from Mazda.ca (canada) . The only number I think could be slightly off is the overall tire diameter because it is calculated based on theoretical values. I have not actually measured my tires diameter, but it should be very close to what I have in this file
 

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IMO, the optimal shift point is much easier to find if you have a dyno graph.

After your peak in horsepower, find where in the drop your horsepower matches with the next gear's horsepower.

Not that simple, due to the fact that finding what rpms the next gear will kick in is a little tough... but a little experimenting works wonders.
 
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