With rain approaching on the radar screen, we could only chance a 20-minute cool-down. We made a couple more passes, posting an 11.87 and an 11.91 at over 119 mph. Totally satisfied with our results, we packed up and headed home.
Before our strip test, we wanted to test Performance Distributors Mini VIP 18-volt step up regulators, but time constraints and a heavy work load at Tune Time's shop prevented it. A few days later it was showtime for the 18-volt Mini VIPs. They added an impressive 8 hp and 7 lb-ft of torque to the equation (458 rwhp, 407 lb-ft). That's enough power to easily be worth a tenth at the track. Due to a stronger spark igniting the fuel in the combustion chamber, the A/F (air/fuel) mixture ratio was a tad leaner, going from 12.7 to 12.9. Tuning in a touch of enrichment could have given us a few horses, but the tune was left untouched.
The Mast Motorsports Black Label heads impressed us beyond our expectations. When you can bolt-on a set of heads that are 46 rwhp better than the great LS3/L99/L92 heads, it's amazing. The Mast Motorsports 12-degree heads show the latest improvements in LS cylinder head technology. We're sure a larger displacement or a forced induction LS engine would be rewarded more power from these massive-air-moving heads.
Note: Looking at important mid-lift (0.300 and 0.400 lift) flow values, besides peak (0.600 and 0.700 lift), the MM heads show they are the highest flowing bolt-on heads available for the LS engine.