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aw4 shift points

J

j99xj

NAXJA Forum User
Location
Colorado Springs, CO, USA
Hi everyone. Just a quick question....at what rpm do your aw4's upshift at full throttle?

Mine shifts at 4800 rpm, and I don't know why it doesn't go all the way to the redline (5250) like it should.

I've done all the intake and exhaust mods so I know the engine is capable of revving to 5250 rpm and still make decent power. I'd love to have an extra 450 rpm while passing on the highway.
 
Last edited:
Mine appears to shift right at the 5000 line.
 
the 4.0 makes the most power around 3500-4000 rpm's no need to rev any higher, it's just excess noise.
 
ktm racer 419 said:
the 4.0 makes the most power around 3500-4000 rpm's no need to rev any higher, it's just excess noise.
Click to expand...

3500-4000 rpms is on the peak torque "plateau" but my peak horsepower is much higher than that. Like I said I've done lots of mods that increase airflow, and I'm almost positive my engine is capable of revving to, and making decent power at 5250 rpms.

I wanted to know what everybodys aw4 shifted at so I could make an informed decision as to whether or not my aw4 is operating correctly. I'm tempted to get the hypertech chip so I can bump the shift points up.

According to my "car test" computer simulation program, an increase in shift point rpm from 4800 to 5250 rpm will reduce 0-60 time by about 0.3 seconds. This is because I'm getting to use that last little bit of power, and holding the current gear longer)
 
ktm racer 419 said:
the 4.0 makes the most power around 3500-4000 rpm's no need to rev any higher, it's just excess noise.
Click to expand...
Thats not true at all, mine pulls hard and fast to the 5250 redline.
 
99XJ at WOT shifts at 4800, I have also been wondering why it won't go further with it in D. I mexishift it when I am racing.
 
My aw4 does about the same 4800 in first gear, and a little bit higher in second, maybe 4950-5000. Like one of the guys said, tach could always be wrong or whatever but still, i think that it shifts early to get you into the next gear early on for maximum acceleration, because that is what you're trying to do when at WOT. I could be wrong, and probably am but according to my dyno charts a little while back it seemed the power started to curve down pretty quick after 4300rpm, and the hp at 4900rpm was matching that of 3500rpm (basically the starting point of 2nd gear once it shifted). That would be my only guess, and I do have an intake and exhaust mods. But id wait for dr.dyno to chime in.
 
On a side note, if my tranny fluid is right above the add mark, would that affect the performance of the transmission significantly?
 
Well last night I was on an open road and I put the tranny in the 1-2 selection and MADE IT hold 2nd gear until I hit the rev limiter just to prove that I could indeed rev that high and make decent power up there.

And I indeed made it to the rev limiter....and boy the little 4.0 still ran excellent. No bad noises, no shaking, just the hum of a full exhaust system.

On a side note the rev limiter scared the hell out of me because it cut in so hard, almost like someone tapped the brakes.

I just want it to shift from 1st to 2nd at 5200 rpms, not 4700-4800 for that extra few seconds of "punch".
 
j99xj said:
Well last night I was on an open road and I put the tranny in the 1-2 selection and MADE IT hold 2nd gear until I hit the rev limiter just to prove that I could indeed rev that high and make decent power up there.

And I indeed made it to the rev limiter....and boy the little 4.0 still ran excellent. No bad noises, no shaking, just the hum of a full exhaust system.

On a side note the rev limiter scared the hell out of me because it cut in so hard, almost like someone tapped the brakes.

I just want it to shift from 1st to 2nd at 5200 rpms, not 4700-4800 for that extra few seconds of "punch".
Click to expand...

You may need a TCM modification or hold the gear manually. Except for racing with a closely matched vehicle, there may be little real advantage for doing this.
 
While on the topic of transmissions, i know i prolly shouldnt do it, but i drop it into the 1-2 positon while going say 35mph and itd go to 2nd gear almost all the time, and then down to 1st gear at around 25mph. But the other day, it decided to go into first gear momentarily then jumped into second gear. Is there any reason for it to do that or was it just a random fluke?
 
BBeach said:
While on the topic of transmissions, i know i prolly shouldnt do it, but i drop it into the 1-2 positon while going say 35mph and itd go to 2nd gear almost all the time, and then down to 1st gear at around 25mph. But the other day, it decided to go into first gear momentarily then jumped into second gear. Is there any reason for it to do that or was it just a random fluke?
Click to expand...

Maybe you had your foot on the gas farther than usual, and that freaked out the throttle position sensor for a second.
 
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