Once the roll bar was installed last Winter, the car sat in the garage for months. It is now Spring and I finally had the chance to action a lingering item on the list: the tune. The car drove around fine, but the power deliverability was noticeably off with the added long-tube headers and intake. It also had a tendency to stall out randomly at idle. The baseline tune that came prepackaged on the stock ECU I bought was probably off the mark as well.
So after accumulating a record amount of dust from laying dormant, I’m pleased to say that the car started right up. This is probably the first car I’ve owned that can sit for months and not require a battery jump or anything particular.
I brought the car to Newtech Performance twice but failed to get the tune underway due to roadblocks with the ECU. The e38 PCM that I purchased with the wiring harness during the swap was security locked out. After trying everything to unlock the PCM on the second attempt, I left the car at the shop and Nick from Newtech was able to help me obtain a new PCM to swap.
Reconvening after the ECU swap, everything was accessible and the long awaited tune was finally proceeding.
Dyno results:
After a meticulous 2 hour tuning session, the car pumped out 427 RWHP and 429 lbs/ft of torque. The dyno curve is super linear and power can be found everywhere through the powerband. The LS7 style MAF was maintained (non-speed density) along with the O2 sensors.
In contrast, my Steve Kan tuning during the Single Turbo days was completed in a 45 minute session after 6-7 pulls. I always felt that it was generalized, ballpark tune and overly rich. Nick at Newtech seemed to be much more careful and spent most of the time going cell by cell in the tables.
The best part is – the motor is essentially stock. The only power adders are the intake setup and exhaust system. 427 RWHP in a 2700lbs car with out of the factory reliability – can’t complain.