Chewy, like any cook-up its down to the Chef when ready but with heat I'm getting from the recent gas fixture it's about 12 - 18 minutes during the cold winter months. When I use coals it's 10% less. Saying that, during summer months in the warm & sunny south (lol) I can reduce cooking times by 15% overall. I reckon your "supercharged" whopper will be throwing them in under 10 mins! I look forward to those results? How's the renovation going mate?
PS. I put up a couple more recent pics of Tandoori Tikka. The prawns pics are not good quality though mate.....
Mr. Punter