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I updated the firmware and load the lc5 on 2012 gtr. I tried to launch at 4500 rmp but it only goes to up 4100 rmp. I also checked the current map from ap it is showing lc5 stock style vdc off. Can someone tell me what could be the problem.
 

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The RPM limit is set by the tuner on the ECU map. Just tell your tuner to set it at 4500 RPM. I have tried LC5 with 4100 and 4500 with tuned GTR and I prefer the Cobb Level 1 or Level 2 LC2.
 

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I have tried LC5 with 4100 and 4500 with tuned GTR and I prefer the Cobb Level 1 or Level 2 LC2.
W/ the 3300 & 3750? why is that, Kerry? I thought LC5 was superior & was going to update on my car.
 

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Is the newest lc5 4500. Really different from lc1 4500?
 

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W/ the 3300 & 3750? why is that, Kerry? I thought LC5 was superior & was going to update on my car.
It's tough to say at this point. Corned killed it with LC4. I like LC5 on the street, but a 4100 LC5 (even more with LC4) at the strip bogged too much and had a decreased 60' time compared to a 4k LC2.

I think a 4500 LC5 will be similar to a 4k LC2 at the strip, but I have not tested this yet. LC5 (and 4) differ on the strip vs the street. On the street, there is some spin at the clutch drop, which keeps the RPM's up and gives you a really nice launch. On the strip, you lose the spin due to better traction, and it bogs more than LC2 at the same RPM, and your 60' suffers

You really just gotta try out different stuff. If I was running DR's at the strip, I would try different launch RPM's with LC5, starting at at least 4500, and go up from there.
 

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Is the newest lc5 4500. Really different from lc1 4500?
Yes, it is very different. LC1 slams the drivetrain hard at the "hit" when you release the brake. LC4/5 is less harsh, more of a fast clutch release vs the felling of a "gear drop" in LC1.
 

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For my step with E85 with nitto invo lc5 is slower and feels harder on the drivetrain than Cobb lc2 level 1 or 2. I also like the fact level 1 rpm goes up slow so you can vary how hard to launch as traction surfaces are different all the time. With lc5, you have zero control.

W/ the 3300 & 3750? why is that, Kerry? I thought LC5 was superior & was going to update on my car.
 

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For my step with E85 with nitto invo lc5 is slower and feels harder on the drivetrain than Cobb lc2 level 1 or 2. I also like the fact level 1 rpm goes up slow so you can vary how hard to launch as traction surfaces are different all the time. With lc5, you have zero control.
Launch rpm is set by the engine ecu, and is different for almost every year. *LC1-LC5 doesn't change the launch rpm*

The Cobb l1 & l2 slowly increases rpms because because it's slipping the clutchs to achieve the higher rpm. personally think that's bad for the tranny

It seems like the results are mixed but I still think LC5 is the best for launching and everything else.

John
 

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Launch rpm is set by the engine ecu, and is different for almost every year. *LC1-LC5 doesn't change the launch rpm*

The Cobb l1 & l2 slowly increases rpms because because it's slipping the clutch to achieve the higher rpm.

John
Two minor corrections for you John:
1. The TCM set the target launch Torque, and then there is a limiter in the ECU. So the launch Torque is set by the TCM and there is a limiter in the ECU can cap out the RPM. That is why the 2010 with LC4 launched at 2200 RPMs and not the 3300 RPM or LC2 or 4100 RPM of LC4.
2. COBB L1 and L2 are just LC2 with the launch RPM raised. We didn't change the ramp rate, that is just how Nissan's LC2 works. Like you said it's hard on the transmission, and LC4 is better.

Joe
 

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Two minor corrections for you John:
1. The TCM set the target launch Torque, and then there is a limiter in the ECU. So the launch Torque is set by the TCM and there is a limiter in the ECU can cap out the RPM. That is why the 2010 with LC4 launched at 2200 RPMs and not the 3300 RPM or LC2 or 4100 RPM of LC4.
2. COBB L1 and L2 are just LC2 with the launch RPM raised. We didn't change the ramp rate, that is just how Nissan's LC2 works. Like you said it's hard on the transmission, and LC4 is better.

Joe
Joe thanks for chiming in.

Yeah the TCM stuff is pretty crazy!

We've been playing around with a few different set calculated of tq limiters in there.

In our tests one set seems to allow the to clutch slip causing Launch RPM to raise ever so slightly over a period of time, while the other set actually allows me to target an calculated tq value which seems to be opening the throttle body.

idk I'm still messing around with some of these tables while trying not to kill our Shep Tranny lol!

But there's no doubt in my mind that you have a better understand on what the TCM / ECU do as I'm only a tuner and your doing the hard core stuff in the back ground.

-John
 

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But there's no doubt in my mind that you have a better understand on what the TCM / ECU do as I'm only a tuner and your doing the hard core stuff in the back ground.

-John
I'm always surprised to see the logic in action. There has been many times when I've though I've gotten the logic figured out only to have a tuner (like yourself) prove me wrong. It really takes a joint effort from both sides to get this kinda stuff figured out!

Joe
 

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Is it just me, I feel like LC5 is harder on transmission than LC2 Cobb. With LC5, I feel like a clutch drop initially and makes a sound and chirps the tires.

Two minor corrections for you John:
1. The TCM set the target launch Torque, and then there is a limiter in the ECU. So the launch Torque is set by the TCM and there is a limiter in the ECU can cap out the RPM. That is why the 2010 with LC4 launched at 2200 RPMs and not the 3300 RPM or LC2 or 4100 RPM of LC4.
2. COBB L1 and L2 are just LC2 with the launch RPM raised. We didn't change the ramp rate, that is just how Nissan's LC2 works. Like you said it's hard on the transmission, and LC4 is better.

Joe
 

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Are you saying that on your car LC4 has a higher launch RPM than LC5?

It's tough to say at this point. Corned killed it with LC4. I like LC5 on the street, but a 4100 LC5 (even more with LC4) at the strip bogged too much and had a decreased 60' time compared to a 4k LC2.

I think a 4500 LC5 will be similar to a 4k LC2 at the strip, but I have not tested this yet. LC5 (and 4) differ on the strip vs the street. On the street, there is some spin at the clutch drop, which keeps the RPM's up and gives you a really nice launch. On the strip, you lose the spin due to better traction, and it bogs more than LC2 at the same RPM, and your 60' suffers

You really just gotta try out different stuff. If I was running DR's at the strip, I would try different launch RPM's with LC5, starting at at least 4500, and go up from there.
 
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