G8 6l80e converter and nitrous not shifting

[RamAir02TA77]

Tuning my brothers 08 g8 gt car has converter and a 150rw shot for some reason before and after the converter the car has a problem shifting on the spray motor is fine but on the spray it hits of the rev limiter the 3-4 shift seems to be the worst. I have lowered shift mph and rpm increased line pressure etc not sure what is wrong I could post a copy of my tune file just need to get it off the laptop but maybe its better off if someone can just take a look at a stock tune and give me a an idea what else I could change... Thanks.

[G8-4-speed]

With nitrous you may be causing the converter to slip more. Being the A6 shifts on MPH, you may just have to keeping lowering the MPH until it shifts at the right rpm. I would drop it 2 MPH for first, 3 for second, and 4-5 for third. Are you changing all normal and A patterns? What mode are you racing it in?

[RamAir02TA77]

Racing in drive we lowered the shift mph and rpm maybe we need to adjust pattern a as well we only lowered the normal table....

[Tapout Tuning]

We started having similar issues once we crossed the 600 RWHP threshold. You may want to join in this thread:

http://www.hptuners.com/forum/showthread.php?t=22991

[n77nxc]

I've been battling the same problem on my 07 Corvette. I'm going to try some new parameters this weekend and see if it helps. I'll report back my findings.

[thesubfloor]

In the factory tune it's set to 1000 (the highlighted cell) and unless you zero it out it'll act just like the normal rev-limiter.

[n77nxc]

In the factory tune it's set to 1000 (the highlighted cell) and unless you zero it out it'll act just like the normal rev-limiter.

Mine is zeroed out.