From what I remember the car was developed around 1986 with the sole purpose of unseating the Mercedes 190E as the touring car king. The only reason the roadgoing version of the e30 M3 became available was due to sanctioning rules the required a certain number of roadgoing models to be produced. Compared to the other M3's the e30 was much more different from its regular 3 series counterparts. Front fenders, rear fenders rear trunk, and metal from the b-pillar back, were all different I believe. Also, there were suspension differences between the regular e30 and the M3 aside from springs and shocks i believe. The s14 engine (remember this was developed in1986) is a high compression, high revving 2.3 liter 4-banger with individual throttle bodies. The euro versoion developed close to 100hp per liter i believe (remember 1986). I dont think parts for the car are as easy to come by as the regular e30 and due to the fact that its a rather high strung engine it needs to be maintained more regularly. Also might have a dry sump(cant remember) The brakes were off of the 5 series sedan as well i believe. Thats all I can really remember off the top of my head... I put three links I had in my bookmarks, i believe i had more articles bookmarked on an older computer. Do a google search. Also its the winningest car in touring car history.
BMW World - BMW S14 Engine
.: Performance CAR - September 1987 :.
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