197 sport. Advice on air filter/ mapping

[Christian J]

Hi all need some advice on what to do with my 197. Had new cambelt and pulleys. Now developed splutter at 2300 rpm to 2700 rpm. I'm thinking now the timing has been put to standard it's spluttering. Happens when foot flat to tge floor . Looks like there's a grill at the front for a cold air feed. Do I go and get a cold air feed straight to the throttle body and get it mapped on a rolling road to sort the splutter out. I'm imagining it's been mapped before and whoever had it took the air feed off. Any advice appreciated. Chris