This may be achieved by pre drying {HEAD ~ means}, such as a pump to provide a stream of air after switch off of the engine, which air may be heated by residual heat from the catalyst or {TAIL ~ engine} 
This may be achieved by pre drying { HEAD ~ means } , such as a pump to provide a stream of air after switch off of the engine , which air may be heated by residual heat from the catalyst or { TAIL ~ engine }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL