Kart5 1 Report post Posted February 22, 2013 Hi, For the E30 series, I'm trying to find what pistons I should be using for my car... I'm wanting .50mm oversize but what is the maximum dome size of the piston I'm allowed to use? And high or low compression? My car is a BMW, 320i, Motronic, M20 B20, approx 1989 year. Any help is appreciated. Thanks! Quote Share this post Link to post Share on other sites
Silver Fox 43 Report post Posted February 22, 2013 .50mm oversize and low compression pistons on Motronic engine, 9.4 to 1 compression and 2.3mm dome. Quote Share this post Link to post Share on other sites
E30 325i Rag-Top 2958 Report post Posted February 22, 2013 NOTE: Must also be from one of the OEM suppliers - Mahle, etc. check the regs carefully! Cheap Chinese copies are not permitted due to the variability in their manufacturing!! Quote Share this post Link to post Share on other sites
Kart5 1 Report post Posted February 24, 2013 Thanks for that. Does anyone know where I could get some? Or a part number please? Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted February 24, 2013 RealOEM for the part numbers. Local sources - Dealer, Euro Marketing, maybe Gavin @ Euro Italian OEM piston suppliers to BMW - Mahle, Borgo or Kolben Schmit Quote Share this post Link to post Share on other sites