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I'm a newb at stick. Can someone tell me the at which revs for the STi I should be shifting in each gear for the best acceleration? "Lowly" passenger cars are out in front of me from a stop, unless I mash on the pedal, which I don't feel I should need too. :(
 

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wie geht es ihnen?
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totally depends on the situation.

normal city/highway driving take it to above 4k RPM before shifting. basically don't let the tranni/engine bog because you're to low in the revs for the shift into 2nd, 3rd, 4th, etc.

having fun/street racing...to REDLINE!
 

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moto

No need for optimum acceleration to outpace 99.9% of cars. For the 0.01% I'd keep the car between 4k-6k with the accelerator floored, which means shifting around 6k.
 

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Drive True
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I remembered there was a thread awhile back in which you could actually calculate the optimum shift points by just doing a little math:

Check here, especially note what WRX_Mundi posted. Of course, if you have mods those shift points will change. :wink:
 

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the motor makes peak power at 6000rpm, so shifting at or slightly above that will get you where you are going in the quickest fashion. there is no need to "redline" the motor at every shift, as the power levels/drops after 6000rpm, you're wasting time...just be smoooooothhhhhh. having that extra 1000-1200rpm before the rev limiter hits is nice on autocross or tight road course sections, where you may not want to shift and then downshift right away. the link nimiz posted does a great job with stressing the need to be smooth as well as quick. don't just yank the crap out of the shift lever.
 

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The lower gear multiplies the torque better, even after the powerband peaks.

You'll still be accelerating faster by waiting til redline to shift.
 

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lupohki said:
I'm a newb at stick. Can someone tell me the at which revs for the STi I should be shifting in each gear for the best acceleration? "Lowly" passenger cars are out in front of me from a stop, unless I mash on the pedal, which I don't feel I should need too. :(
For best acceleration, you want to shift at a point where you will fall back into the peak torque of the engine. I have my shift light set at 6200RPM, by the time I see it and shift I'm near (but not on) redline. After the shift I'm right back in the meat of the torque band (above 4k RPM) and still pulling hard.

Contrast this to shifting too early, say 5000RPM and dropping down to 3500 or so after the shift. You will have to work the engine back up to speed (and turbo) and you will notice it.

But for normal driving I shift anywhere from 4000-4500 RPM.

Dyno chart showing peak torque from 4k RPM on:

http://www.vishnutuning.com/sti_dyno.htm

Hope that helps,

-st
 

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Legacy GT only 250hp

Also shifting smoother is better then shifting hard (dont pop the clutch out so hard). I did some practicing of shifting fast, but smooth and man does it feel like it pulls 10x harder.

Robert~
 

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It might feel that way, but if you're trying for MAX acceleration, you're best bet is to keep it floored the whole time, and drop the clutch after shifting.
 

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Pensacola STi

Back in June when I first got the car, someone posted a plot of the effective torque curve for each gear on one chart.

I've just searched all over for it, and I just can't find it. It was basically just a plot of the torque at the wheels for each gear. You could tell the proper shift points by just looking at where the plots overlapped. Based on that chart, it was best to stay in first until redline, and then until 6k or so for the rest of the gears.

Jim
 

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bitabur said:
It might feel that way, but if you're trying for MAX acceleration, you're best bet is to keep it floored the whole time, and drop the clutch after shifting.
ya the reason it felt faster (now that I realize what is going on) is because It jumped to 17.5 PSI in 3rd... i didnt realize i was getting boost creep in 3rd until today.

Robert~
 

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jim said:
Back in June when I first got the car, someone posted a plot of the effective torque curve for each gear on one chart.

I've just searched all over for it, and I just can't find it. It was basically just a plot of the torque at the wheels for each gear. You could tell the proper shift points by just looking at where the plots overlapped. Based on that chart, it was best to stay in first until redline, and then until 6k or so for the rest of the gears.

Jim
I have a spreadsheet on that if you want it. Back in the summer, I ran some calculations, as did someone else on nasioc. Basically the shift points are roughly:

1st : Redline
rest of gears : ~6600-6800

The gearing is pretty well set up for the powerband of the engine. My shift alarm is set for 6500.
 

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No, I still have the plot in my office somewhere. Thanks though...

I also have my shift light set at 6500. It goes by so fast in 1st it works there too! ;)

Jim
 
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