Hi Doc,
I am from the Newmarket area and buddy is pretty good if its who I think you went to. But the best would be Champion Motors in Scarborough. They do a lot of tuning for LS engines. That would be my recommendation. Give them a call and see what they say. I have a 2014 ZL1 Camaro also...
When I got home from buddy I bought it from ran awful and rear end was making the usual noise of old oil/ no additive. AC would not shut off causing the engine to work harder lots of work ahead.
Burnt wiring harness due to someone wiring the curiosity lights wrong and I put bulbs in and did not notice until it lit up under the dash while driving.