As an owner on 9 (yes 9 !) /mk2 Escorts currently, my current tally is six 2 doors and three four doors... Two of the 4 doors are the rare Midnight Blue factory colour too (One for sale too).
Two doors for racing are much more sought after (mostly flat fronts, but some like the RS front too) and that is one reason 2 door shells is Aus have skyrocketed in the last 5 years. My two doors are mostly well modified (race/rally/autocross and motorkhana), but the 4 doors are substantially cheaper. hence why my four door RS was originally bought. It was used on the road for over 10 years by me - only coming off general road duties 2 years ago - its mods were limited to LPG and a 5 speed to suit its purpose at the time.
Ultimately it will come down to YOUR preference as I actually prefer 4 doors for the simple reason that it is easier to reach the seatbelt.... (first 2 escorts i looked at back in 88 were a tow and a four door and that is where my preference came from at the time.) But 2 door are easier getting into with a full cage...
A major factor now will be condition - remember the youngest Mk2 is now around 32yo (excluding the RACV vans) - so condition and availability of parts/panels is now an issue.... Having both I can tell you it is much easier AND cheaper finding four door parts than two door parts..... I have 2 sets of good 4 door trims, but getting a 1/2 decent set of 2 door ones (yes you can buy them repro - but at $880 pair...) and I have been trying to collect a decent pair of 2 door trims for few years now...
Prices - For a reasonable condition four door you will pay around 20-30% less. My 4 door for sale is asking $4.5K and is mechanically strong, but bodywise is going to need a tidyup, but if it were a 2 door I would be chasing $6K for it. GDub recently sold his EC 4 door for around $10K, but around 6 years ago got $13K for an EC Monza Red 2 door. Do you want it to drive or for collecting or as an investment. One of my 2 doors I am keeping as a "spare complete" shell, but if I got offered the right money then it would go now as I figure that the demand for clean rust free shells is only going to go up over time as they become harder to find in GC.
Collectability - RS2000's are always going to be more costly than flat fronts and therefor more likely to be more pampered. Looking at Small Ford Sunday over the last few years has seen a substantial relative increase of pampered 4 door RS's, but the 2 doors still outnumber the 4 doors easily. Colour is a factor and most RS's seem to be Monza Red (also my choice of colour), but second most common are PinenLime and White. Only once have I seen at SFS another Midnight Blue RS (4 or 2 door), and silver and black are very (very!) rare. In my 15 years of having my midnight blue RS I have only ever seen two other 4 doors and a single 2 door on the road in that colour. (I have heard of another couple being restored in the 2 clubs I am in). What was scrapped only a few years ago, would have been worth $$$ in a few years. Look at England - they all want 2 doors, but some magazine feature cars are being built on 4 doors now as the 2 door prices are very very high and dragging up the 4 door prices too.
Ultimately it will come down to
- Condition, condition, condition (as they say in real estate...)
- Price
- Collectability
- Modifications (over the top / non period type modifications do hurt a cars value and this factor is now coming into play and will become more so as time goes on
- Why you want it / What you are going to use it for............
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