Problem when no-lift shifting...

[Cossey]

Happens at the strip and on the street. When I NLS into 4th, the car like, hits a brick wall for a second, then slowly regains it's speed. I still managed a 14.3 at the strip, but it annoys the piss out of me. I dind't have a problem before when I went 14.1, but now I do. It happened once going into 3rd. I have a slight tune by a local person who's flashed my map onto another LGT and he's had no problems whatsoever. Someone please help!!!

[dr. pepper]

5MT or 5EAT?

[mwiener2]

do you mean flat foot shifting?

 

The hesitation you're feeling is the car hitting the rev limiter. You've probly beat the crap out of the stock clutch and now it's starting to slip and letting the engine hit the rev limiter

[wichitalegacy]

do you mean flat foot shifting?

 

The hesitation you're feeling is the car hitting the rev limiter. You've probly beat the crap out of the stock clutch and now it's starting to slip and letting the engine hit the rev limiter

 

+1

 

This happend on my stock clutch with the 20g.

[mickeyd2005]

OP, if you want to do flat footed shifting you need to raise your boost pressure resume.

 

My guess is that you momentarily hit the rev limiter. Fuel won't be resumed until boost pressure drops below a threshold. You need to raise that threshold so that boost comes back sooner. That way you can just bounce off the rev limiter.

 

My buddy shifts his evo in the quarter mile that way. I'm not sure the LGT 5MT clutch can handle it.

[Cossey]

Yea, we tried raising the boost limit a little bit, but no help. Maybe I didn't raise it high enough?

[PhilT]

I don't think this is the rev limiter, as I've done the same on occasion.

 

I believe it's the transition from open to closed loop, it feels very weird, but if you just lift off a little then press down again it's fine.

[mickeyd2005]

I don't think this is the rev limiter, as I've done the same on occasion.

 

I believe it's the transition from open to closed loop, it feels very weird, but if you just lift off a little then press down again it's fine.

 

There is no way that he is in closed loop on the strip.

 

OP, can you post a datalog? I would like to see your boost pressures at redline and what did you increase your resume pressure to?

[PhilT]

There is no way that he is in closed loop on the strip.

 

OP, can you post a datalog? I would like to see your boost pressures at redline and what did you increase your resume pressure to?

 

I'm not saying it is, just maybe. This has happened to me and it's not the rev limiter.

 

This was the opinion at the time : http://www.legacygt.com/forums/showthread.php?t=44545

[mickeyd2005]

I think this is different.

 

He never lets go of the gas so he never transitions back into closed loop. The only time he is in closed loop is in 1st gear at idle.

 

And... I am surprised that in October 2006, you were still running long CL/OL delays. Most tuners use 0. I use 100.

[PhilT]

I think this is different.

 

He never lets go of the gas so he never transitions back into closed loop. The only time he is in closed loop is in 1st gear at idle.

 

And... I am surprised that in October 2006, you were still running long CL/OL delays. Most tuners use 0. I use 100.

 

I don't tune my own car, or even attempt to understand how to

 

I am still using the TDC tune that I was back then, and the problem never reappeared.

 

It sounds like the same problem though, changing from 3rd into 4th, without coming off the gas enough.

 

There is a delay when transitioning from closed loop to open loop; when you are really on it and let off to shift then go WOT again, the ECU delays the transition back to open loop, which is what you are feeling. You can test it pretty easily by doing a WOT run and keeping the throttle open more then 40% during shifts (a little old school powershifting), but you might not want to do that

[Cossey]

I'll try to get a log ASAP. The map and such is ony my friend's comp, so I'd have to have him upload it.

[2005garnetGT]

I don't tune my own car, or even attempt to understand how to

 

I am still using the TDC tune that I was back then, and the problem never reappeared.

 

It sounds like the same problem though, changing from 3rd into 4th, without coming off the gas enough.

 

I'm betting its the revlimit fuel cut resume problem that I experienced.

 

a datalog including the powershift will show whether it is or not.

[mickeyd2005]

I don't tune my own car, or even attempt to understand how to

 

I am still using the TDC tune that I was back then, and the problem never reappeared.

 

It sounds like the same problem though, changing from 3rd into 4th, without coming off the gas enough.

 

Read Rob's post again.

 

There is a delay when transitioning from closed loop to open loop; when you are really on it and let off to shift then go WOT again, the ECU delays the transition back to open loop, which is what you are feeling.

 

OP never let go of the gas.

 

The powershift that Rob described is probably to show how not to make it happen.

[PhilT]

Read Rob's post again.

 

OP never let go of the gas.

 

The powershift that Rob described is probably to show how not to make it happen.

 

Now the full quote

 

There is a delay when transitioning from closed loop to open loop; when you are really on it and let off to shift then go WOT again, the ECU delays the transition back to open loop, which is what you are feeling. You can test it pretty easily by doing a WOT run and keeping the throttle open more then 40% during shifts (a little old school powershifting), but you might not want to do that

 

 

[2005garnetGT]

Now the full quote

 

[/i]

 

there is a happy valley between going back into CL on the less throttle end, and smacking into rev limit fuel cut resume on the high throttle end.

 

I'm guessing you fall under the latter, because you said "not letting off enough", which implies near WOT.

[mickeyd2005]

Now the full quote

 

[/i]

 

Phil. Read the entire quote form rao.

 

I deleted that part because I believe it was an example of how to show not to make it happen.

 

OP, NEVER let go of the gas.

[mickeyd2005]

And the read the part that I highlighted.

[frathouse87]

So is only halfway lifting off the gas between shifts faster in the 1/4?

[Cossey]

Since I was the one who originally brought up the topic of NLS'ing, here's my disclaimer:

 

I ____________ agree that if any damage to my car was done from attempting to no-lift shift, I can not pursue Chris Cossey for any costs of repair, damage, or just for personal benefit.

 

Please sign on the line.

 

=) j/k

 

It's not something I recommend if you can't shift fast really. I've done it on all of my cars accept for my DD Accord way back when, so far so good.

[mwiener2]

I still think it's just your stock clutch crapping out like many others have

[GTTuner]

My car will shut right down if I try and do WOT shifts. The first time I did it, I thought I blew the motor....as I was coasting of to the side of road.

 

Just for the record, I am well versed in WOT shifts. The Legacy just does not seem very happy when asked to do so.

[2005garnetGT]

My car will shut right down if I try and do WOT shifts. The first time I did it, I thought I blew the motor....as I was coasting of to the side of road.

 

Just for the record, I am well versed in WOT shifts. The Legacy just does not seem very happy when asked to do so.

 

thats the rev limit fuel cut resume wall you are smacking into, raising the threshhold will eliminate this problem

[GTTuner]

^^^^ I have not tried it since I got my tune and raised the limiter to 7200. When I have a new clutch in hand I'll try it again. I think this stocker will shred.

[2005garnetGT]

^^^^ I have not tried it since I got my tune and raised the limiter to 7200. When I have a new clutch in hand I'll try it again. I think this stocker will shred.

 

no tuner fixes it, they don't know what it is.