It shouldn't do, it will provide a colder denser air charge and produce more torque.It can do " harm" regarding affecting the performance at certain times/revs compared to leaving std one on. Its not just as simple as sticking a bigger intercooler on
The remap allows the intercooler to be enhanced to it's full effect, it's not a necessity. Whilst the intercooler I fitted to my car was purpose designed by Airtec and cost about £300, many people have fitted a generic Racebits larger intercooler to ST TDCi's at a cost of £100 and had the same results, so long as the air in and out pipework is in the right place there is no problem. Before the Airtec and Racebits intercoolers, people were fitting Mk2 Focus ST intercoolers but had to alter some of the boost hoses as it didn't have the same layout. All three intercoolers still worked fine however, even without a remap.Each to their own Neil. The intercooler you used "may not" be suitable for my car (even if I made it fit)If you do research you will find that it is not just as simple as sticking a bigger intercooler on.
As you state "Remapping the car properly afterwards to allow for the intercooler", so you confirm that it is not just a matter of fitting a bigger intercooler
So do I.I have worked in experimental, engineering, road test and development