i was going well above highway speeds, ill admit that. i can get up to 60 in 2nd before hitting the rev limiter and at 6,500 revs in 3rd is around 90 mph

ill try and make a video of this drop happening, but i dont know any good roads around here

 

I must go beat the crap out of mine if I-VTEC does not kick in until 5400 and see what it is like.

I run a Canadian 09Sport with Auto. No paddle shifters. I was finding when using on ramps even though stuck to the floor it would want to up shift at various times. It was never consistent. Now I am in that gas saving mode of driving around the city in D3 and now when using on ramp leave it there til get up to around 100-110kph (5000 rpm approx) then blip the throttle and up shift to D . Much more fun.

D3 also makes the HKS sound a bit better.

 

I'm with Lyon[Nightroad]....with an automatic a bit of RPM drop which is not a shift could simply be the converter locking up-- despite the fact that your foot is to the floor. A downshift on a long hill is preceded by an RPM jump as the converter unlocks...then the downshift makes for a much bigger RPM jump. It makes sense...but then I'm no expert on VTec cam stuff. If it doesn't do this with a manual trans then the lock-up converter explanation starts to make a little sense, though.

 

Alrighty... I decided to try again.

Apparently, I didn't rev bounce in 2nd or 3rd before. I thought I did, but it turns out....

1st gets to 30
2nd gets to 55
3rd gets to 80

bounce@7k rpm

Its still the same 80 mph I listed in the other thread (about what you did in the Fit today), I think it was that I simply got really close to 7k rpm and got nervous and shifted. This time, I actually let the engine go up and down as you would if you continued to throttle it without shifting. The rev bouncing doesn't appear to be any more than about 250 rpm or so, the wavering needle doesn't move much.

I didn't notice anything at 6500 other than starting to get nervous myself. What can I say, I worry about doing something newbie, like ruining a brand new engine.

All that being said... it looks like Lyon[Nightroad] might be right in that it could be the torque converter locking up or at least something specific to the AT.

I'm trying to imagine what would be going on... if it's the converter.

Its unlocked throughout most of the rpm range... and as the transmission RPMs, or rather the RPM input shaft (from the converter into the transmission) gets close to the RPM of the engine, the converter locks up. By locking up, the transmission puts the full force of the gears onto the input shaft and the engine basically sees it as additional load, causing the RPM to drop slightly.

But I assume this can only happen if the RPM is climbing at a "slower" (creeping?) pace so that the transmission rpm can catch up? Otherwise you would most likely shift before it locks up?

 

sorry, what i meant by creeping was the the rpms in general, the fits slow enough, and to get to higher rpm (especially in higher gears) takes some time. i was flooring it the whole time

i really want to try this again, ill try to try tomorrow night....

 

So then, maybe the ECU is programmed to do this when it hits 6500?

I mean, below 6500 rpm, the converter locks up when you're cruising at/near a constant speed, right?

 

TC lockup could explain the odd RPM fluctuations.

Really, a manual wouldn't experience this. You are either.. going or not. If you are turning a certain RPM you will be going a certain speed regardless. In an auto where the TC slips a bit you start to see the characteristic RPM drops or increases as it locks and unlocks.

 

Finally got a video of this in action. It happens very consistently. You'll see it has the effect of keeping it in 3rd gear almost all the way up to 100 mph. Interestingly enough it seems to accelerate almost as fast after this from 85-95 as it did from 75-85. I can't help but wonder if there is some untapped power that could be unlocked with a pcm... nevermind who the hell is going to make an AT pcm tuning solution for a honda fit when we don't even have anything for the ecu, fuel, timing, etc....

One of the other benefits of this that I did not get in the video is that it has the effect of getting you higher up in the power band when you get to 4th gear so that you don't bog down in the sub 4000 range.

Imageshack - file5942.mp4 - Uploaded by fallidar
Sorry, all out of NAAAWWWWZZZZ when I recorded thisthis is an all motor run.

 

only in 3rd gear, you'd never notice it if you never go over 85.

 

excellent video! Thanks for taking the time to show exactly what we are all talking about.

 

thanks for the video, thats exactly what happened to me. i was jw if it was just me

 

Sorry for reviving this thread

But yeah i also experienced this lately during my track session. 1st to 2nd no prob. Limit was around 7k

2nd to 3rd no prob again. Limit again at 7k

Then here comes 3rd to 4th.. Reaches maybe around 6.2-6.5k then drops at 5.5-5.7k without me lifting my foot off the pedal.

Since i've been reading that it MIGHT be the cause of the TC. Is the situation normal? I couldn't rememberthis happening to me on my previous runs.

Would changing ATF, cleaning the grounds and MAF sensor, as well as resetting the ECU help?

Car is an A/T by the way. Using paddle shifters all throughout

Thanks in advance!

 

Maybe it's Honda's way of saying... you're going too fast? lol

Maybe try to nail the timing of when it does it... and then plan to shift at the same time?

 

Lol not sure if thats the way my fit tells me im going to fast. :lol:

But yeah its not the limit because when it drops down it still creeps back up and can do upto 7k. Im not sure if its slipping but its an auto.

Would like to hear though if its a normal behavior.

 

This happens to me as well. And because nobody has declared otherwise, I hereby declare this behavior normal. :P

I also tried leaving the AT in D, paddle shift to 3rd, then flooring it. Revs climbed to ~6600 rpm, then car auto shifted to 4th. No rpm drop noticed.

Any mods on your car?

 

LOL!

That declaration was EPIC!

Anyway, no mods on the car except for coilovers, wheels-tires combo and a rear sway bar. Thats it. )

 

Ah, that is more evidence that the behavior is normal. Would it be possible to threaten Honda saying "make us a Flashpro so we can fix this, or else .... [insert threat here]"

Sigh!

 

I am seeing the same thing. My tuner believes is torque converter related. I am running an additional tranny cooler. Going to check the fluid and for leaks today. In the attached photo is the graph from 3rd gear pull and around 6K it drops. Rev limiter set to 7100. I am in a GD3, sorry

https://dl.dropboxusercontent.com/u/...2/IMAG0725.jpg

 

Errr i forgot i got a K&N drop-in filter. lol!

But if its a normal behavior, why don't everyone here experience this? Or they just don't go to that limit? mehhh

 

hmmm so if its a torque converter related, how can we eliminate this? and is it even possible?