Thanks guys - yep, it's an odd feeling getting so much attention.
Today was a pretty fun day - I took the car down to Excelsior Motorsports in Escondido for an engine tune. The weather was super dicey (raining) and I haven't installed my side windows yet which made for some hemming and hawing from me. I debated canceling the appointment but decided I would roll the dice and hope the car could outrun the rain. Lucky for me, it did!
Excelsior Motorsports uses a Mainline ProHub dyno - it's one where the dyno is hooked up to the drive axles via your wheel studs. The rear wheels are removed entirely for the tuning process. This type of dyno has been labeled the "heartbreak dyno" because they typically report numbers lower than you'd see on a DynoJet dyno. I asked Kushan, the owner of Excelsior, to hook me up with a solid street tune and idle. I wasn't gunning for peak horsepower numbers.
We had some difficulties trying to get the ECU to respond. Apparently if you're running an Aim dash it will draw too much current from the CAN signal and cause the OBD2 port to shut down. After about an hour of trying to diagnose the issue I got desperate and called Allan. Of course Allan had seen this before and suggested I yank the dash. Yep, that did it!
We got the car on the dyno and Kushan started doing his thing.
It turns out the factory GM tune runs the car pretty lean - at about 14 AFR. From what I've gathered these engines like to run closer to 12.9-13.1. Kushan adjusted my fueling and played around with the idle. He also discovered there were a number of settings in the ECU that were left off (that would normally be on). So he basically went through the entire ECM and cleaned things up.
Here are my heartbreak numbers:
Before: 424.7 hp / 345.1 ft-lb
After: 448.8 hp / 364.4 ft-lb
I'm pretty pumped with how things went. I feel much more confident getting into the power now, knowing my fueling has been corrected and idle behavior seems improved. On that note - Kushan did note he thought my MAF sensor was a bit too close to the air filter and that it might be a reason for unsteady idle.
As always, more discussion and photos on my blog.
56. The heartbreak effect