Warrtalon

iTrader: (6)

6800 is FAR from optimal at the drag strip. You won't get anywhere near my times doing that. Even when I was bone stock, I shifted higher than that. 6800 is right after peak HP, but that isn't the main factor when deciding when to shift. When you shift at 6800, you're not in the sweetspot of the next gear...

wiretap

iTrader: (2)

Thats what I was trying to get at.. the sweetspot of the next gear, where the powerband takes off and goes up in hp/torque. It can make a pretty big difference, even though you may lose a fraction of time in a quicker, lower gear.

plokivos

iTrader: (3)

i guess i left out if you're not tuned. there's really no need to go up to the redline on not tuned evo with slight mods (catback, etc.)

AcA

iTrader: (2)

i was shifting 7500rpm + and was trapping 106 at best and gave shifting 7k a try and started to trap 108 even 109 in one run. so i think its best shift at 7k if you don't have cams.

Warrtalon

iTrader: (6)

Why not try in between? 7k is better than 7500, but 7200-7300 is better than both.

In stock form, I used the same shifting method en route to the stock time listed below. THe only thing that kept me from 13.0s or 12.9s was the 5k limiter that I was not familiar with at the time. Shifting before 7k is never good for an Evo with a 2.0L.

RazoEvo

iTrader: (4)

1st and 2nd gear bring it up as high as you can JUST before redline, shifting fast and , when shifting into 3rd bring it up less then 2nd, and into 4th if you do even less then 3rd, and make sure you shift rather smoothly, not neccessarily fast, this will help you keep a good trap speed. 1st and 2nd are set up gears, if you do those right, 3rd and 4th are just for trap.

YellowEvo03

iTrader: (1)

I'd beleive in shifting b/f redline if you don't have the boost taper. However, once that is fixed, I'd say take it to redline. I don't have a dyno to back me up, but the car obviously does not stop pulling after 6500 like it used to. Probably b/t 7k and redline is the best.

Ludikraut

iTrader: (17)

Shift points are no mystery ... do the math. Your optimal shift point is determined by combining your gearing with your torque curve. To see an example of the math for our Evos, go HERE.

l8r)

Warrtalon

iTrader: (6)

That's good theoretical work, but you have to remember that not everyone shifts at the same speed or with the same method. For instance, my 3-4 shift is almost always a powershift, so my revs don't drop at all. My 1-2 and 2-3 are lightning quick, and I don't completely lift my throttle foot, although I do not keep it to the floor by any means. An even slower shifter would have trouble with those shift points. I've found that 7k is too low on my car, but I have a 6spd.

Ludikraut

iTrader: (17)

Shifting style really doesn't matter. For example let's take a 3-4 shift on a stock Evo transmission. Shifting at 7000rpms has you going ~83mph ... now during your shift your car bascially coasts and really doesn't lose much, if any speed. So let's assume you're still going 83 mph as you hit the gas again in 4th ... 83mph in 4th gear puts you at ~5100 rpm. Whether you let your rpms drop during the shift, or whether you shift while never lifting off the throttle, you will still end up at 5100 rpms in the next gear. RPMS and gearing and speed have a fixed relationship. The most important thing to consider in figuring out where your shift point is (assuming stock tranny), will be the power curve of the car.

Of course, if someone has problems shifting at the optimal point, because they can't get it into the next gear (i.e. the dreaded 1-2 shift for a lot of Evos), that's a much different issue altogether...

l8r)

Ralliart_on_LSD

iTrader: (8)

whats trap speed?

Warrtalon

iTrader: (6)

This is definitely not true in reality. Do you drag race much? When I shift, I'm never below 5600 in the next gear. You definitely slow down and lose rpms with slower shifts. This has a MAJOR impact on ETs and trap speeds. For instance, before I encountered my clutch lockout problem, I could run 12.1 at 111 with my shifting method. Then, when I had to compensate for the 7k lockout problem, I made a pass with quick shifting, but nothing like my normal snapshifts, and although I didn't miss any shifts, I dropped to a 12.67 at 107. Your hypothesis/theory/guess is way off in terms of real drag racing. If you drag raced with any regularity, you would know this to be true. Shifting speed makes a HUGE difference in both rpm and SPOOL when engaging the next gear, so the "power curve" of the car is NOT the most important factor for determining shift point.

Ludikraut

iTrader: (17)

I agree that shifting speed makes a difference as far as spool goes, as a matter of fact, if you go to a NLS system (no lift shifting), your stock turbo should never drop below 10psi with mediocre shifting speed and it'll stay all the way up at ~17psi if you shift fast. Keeping your turbo spooled and the fast shifting will also have a significant effect on your ETs. Going from regular shifting to NLS can drop your ET by as much as .5 seconds.

However, the rpms still don't change and your power curve also doesn't change. If you were to datalog your drag runs, you would see that the rpms will be very close to the calculated numbers. They may vary +/- 100 rpms depending on how much you let your clutch slip and the state of your tires, but that will be about it. The fact that you stated that you are never below 5600 rpms during your non-inhibited runs, supports this point, since shifting close to redline will put you right around, if not above 5600 rpms (depends on the gear). Incidentally most modded Evos should be shifted as close to the redline as possible for maximum power. My optimal shiftpoint with an AMS 3071 currently resides between 8000 and 8400 rpms. The gearing is also why the fastest drag Evos rev to 9K, or even 10K rpms.

l8r)

Warrtalon

iTrader: (6)

This is contradictory to what you wrote earlier, though. If people in Evos with stock turbo and stock cams were shifting at redline, that would completely go against the earlier "power curve" argument, because we hit peak HP before 7k and have a major drop-off in power 7500.

I do datalog my runs and I _don't_ shift at redline. I shift around 7200, but then am never below 5600 in the next gear when doing my fast shifting method. When I had to shift slower, even though I shifted at the same rpms, I went all the way down to 5300 in the next gear. That made a HUGEEEEEEEEEEEE difference and was all due to slower shifting.

Ludikraut

iTrader: (17)

It's not contradictory to what I posted. I never said that you are supposed to shift at the peak HP point. You shift when the current gear no longer puts down more torque than the next gear ... ie: if your in 2nd gear at 7000 rpms, putting 3000 ft-lbs of torque to the ground and 3rd gear at the same road-speed puts the same amount of torque to the ground, then that's your shift point. If that intersection happens at a different rpm, then that, in turn, becomes your shift point. To see an illustration of this, click here.

I also agree that faster shifting will make you go faster ... no denying that. If your shifting consistently has you slightly ahead of where the gear-ratio normally falls, then you might even be able to squeeze another tenth or so by going back to a dyno plot of your car and looking to see if you wouldn't be better off shifting slightly higher or lower.

Care to post your datalogs? I'd be interested in seeing a real-world example of what we're discussing. Also, how high do you keep your revs in between shifts?

l8r)