Cobb Tcm Question

[Martin Donnon]

I still don't get how LC makes any difference to the gear changes. I'm running LC5 and it's no different to my old LC2.

Its a whole different piece of TCM software. Its like upgrading say from Windows 95 to Windows 7. All the clutch engagement ramps for normal driving, shift points, apply pressure maps - everything is different - so there is lots of difference in the gearchanges.

[g35me]

I realized last night what was going on. All I was doing was changing LC only and not changing the TCM software as well. So I followed your instructions and will test it out today.

[domino_z]

Just finished upgrading my accessport

Fun times ahead

[g35me]

Ok. Driving the car today the shifts seem smoother. No screeching from 2nd to 3rd when a little cold so that's good. Still need to adjust the cc and tp slightly but overall its much better. Smoother and quieter shifting. Well worth the upgrade to NIS-006.

[Speedah]

Its a whole different piece of TCM software. Its like upgrading say from Windows 95 to Windows 7. All the clutch engagement ramps for normal driving, shift points, apply pressure maps - everything is different - so there is lots of difference in the gearchanges.

Agree, since you installed LC4 on my car it is very smooth on light throttle take off....old LC? was very jerky.

[Wardski]

Does upgrading to LC4/5 via accessport definitely void the warranty??? Is there any way the dealer can do it??

[g35me]

It's the transmission software, so I would say yes.

[Wardski]

It's the transmission software, so I would say yes.

But isnt the transmission software by Nissan? Hmm

[domino_z]

No it's provided by Cobb

[domino_z]

I installed the 'kb15b lc4 stock' map and the shifts are definitely smoother, most noticeable is that the lurching while de-accelerating has completely gone

I haven't installed any of the launch control maps and am still using my factory vdc-r lc3

Though there are a few changes - lc3 was activated with everything in r mode before the upgrade, but now I can launch with suspension in soft mode and in full auto mode

Seems a bit more aggressive and was able to run a 3.1 0-100 in auto mode with it short shifting 1st. Must have been a fluke or vbox anomaly because I couldn't replicate it - next runs were 3.3 and 3.4 in manual and auto mode again short shifting

Going to stay with lc3 as the 3200rpm launch still gives me far too much wheelspin, and ill wait for Cobb to release user selectable launch rpm

Edited October 22, 2012 by domino_z

[domino_z]

further update

driving to work in stop start traffic was so much smoother, i actually found myself leaving it in auto mode and wasn't getting the lurching changing 1st to 2nd on very small throttle openings. I was very suprised how much it has improved

i have read lc5 software is even better for auto mode and will hold 3rd a bit longer, and that's really all the auto mode is missing

Nissan dealers really should have rolled out some kind of continual software upgrade for existing owners. In fact the r35 is the only car (dc and semi manual) i can think of where i haven't got software upgrades during scheduled servicing

Edited October 22, 2012 by domino_z