197 sport. Advice on air filter/ mapping

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
 
Get it remapped. Whoever does it should be able to tell you if there was a map in there already. If it is standard they can probably smooth out the power delivery.
 
No. Two years I've put up with the car kangarooing. Changed the map sensor. Changed load of other things. It's going on diagnostics at ktec to find out what's going on. I've bought a ktec filter kit. Get rid of the standard airbox at least that will give some gains