Here's one of my very own cars, a 67 Camaro. I'm running a generation I 355 CI LT1 from the early 70's. The engine is near stock with the exception of the 0.030" TRW replacement pistons, an Isky solid flat tappet cam and a set of  67cc combustion chamber AFR street heads that lower the compression to 10.7:1. This was my first attempt at grooving heads and it's been running for about a year.
 

All of the benefits were realized on my first attempt. The engine idles like never before at 700 RPM. Last weekend I made six passes consecutively all within .02 seconds of each other. I made it to the 4^th round of eliminations when a late reaction ended the fun. I wonder if the grooves help to stabilize combustion to aid consistency. Well the engine is running better than ever and I send my thanks to Somender.