I have had some experience with both engines, personally a dead stock 1.8 ZETEC runnning carbs was almost identical performance to a very worked injected pinto. This was evident during a FOSC run at bathurst in 2009. There was basically nothing in it. #95 (zetec) #172 (pinto)
http://racing.natsoft.com...ct_34402928.94F/View?3 http://racing.natsoft.com...t_34402928.94F/View?21 I since swapped out the 1.8 for a st170 lump again dead stock and using the same carbs 45mm dellortos. And took close to 15 seconds of a lap time at bathurst the following year.
So after spending close to 5k in 2008 building the pinto that went pop up mountian straight, I changed camps to Zetec, the 1.8 was $150 the st170 $1250, both motors copped an absolute flogging and while I can't comment on the 1.8 the st170 is still going strong and produces 146 rwhp while not as big a figure as the pinto at 159 rwhp, it has been ultra reliable and after the initial expense of conversion parts the economies are valid, say a max of 2k for an st170, opposed to 5k for a hot pinto...
I know the St170 has more potential but its tops as is and super reliable.
I doubt there is many pintos running punching at this level. for cost, replacement cost, reliability, and power delivery.
In summary qualitfying times
very hot pinto 3:09.75 DNF event
1.8 zetec 3:01.95 (stock internal) Competed all weekend
ST170 2:54.83 competed all weekend
EXACTLY the same car.