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are you saying that there is a difference between engine torque and wheel torque?
Yes. Like said above, gear ratios are of paramount importance. Gears multiply torque, thats their purpose. The graph you see from a dyno chart is the engine's torque characteristics, and HP is calculated from that. The actual force being put to the wheels is a function of engine torque (at that rpm) and the gear you are currently in. The point is at redline in 1st gear, with our transmissions, you will be putting more torque to the ground than if you shifted up, because shifting up changes the gear ratio. You must compare these two figures. The only time you'd shift before redline is if you'd be exerting more torque on the wheels in the next higher gear than the gear/rpm you're running at that moment. Does that make sense? This is all blatantly generalized, but most people don't think about this, they only think about engine torque or power. On the other hand, there -are- cars with trannies that SHOULD shift before redline, thats why this isn't universal either. It all depends on the tranny/engine combo and how the engineers designed it to all work together.
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I have tried shifting at around 6000 RPM and I have tried shifting higher. I ran faster when I shifted at 6000 RPM. This is the way I feel about it...Peak torque is at 4000 RPM and peak HP is at 5600 RPM and goes down after that. So, shifting after 6000RPM seems pointless to me, you are way past peak torque, and past the peak HP. Here is the dyno of a stock ECOTEC:
As for the short shifter---get the B&M, at least you know it's quality and comes with a warranty.
i have heard though if you run it up to red line that puts you right in the good torque range for the next gear. So yeah your not making anymore power but the next gears power comes alot faster. Its all pereference though. What ever makes you run faster is what i would go with.
My Sig Was To Big
red04cavy: While your observations about the engine seem to be correct, you're missing the bigger picture. You
MUST take gear ratios into consideration. You can't just look at the engine torque band and decide when to shift. Instead of trying to push my interpretation, maybe you will believe
this article. I guess a few good articles come out of these magazines once or twice a year after all. Cheers.
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i say stay in first and never shift. EVER!! haha j/k i shift my eco just before redline. although once i get close to 6k i can feel the loss of power, i am in the powerband of the next gear already. i tested this yesterday. my friend has an identicle car. he shifted at 6 and i shifted at about 6400. i won... then we switched it up and he shifted at 6400 and i shifted at 6. he won. we did this about 4 or 5 times and it was the same outcome every time. according to that graph up a couple posts it seems smarted to shift sooner, but i was actually faster shifting at redline. this is just my opinion and my own little retarted testing, but i think ill @!#$ at redline from now on.