wrs 120 Report post Posted October 25, 2021 Yeah, thanks, that could work. The S50 injectors should flow about 7% more which likely won't be quite enough but if I also increase the fuel pressure a small amount by replacing the stock regulator with an adjustable one it should be possible to set the fuel pressure required during the tune to make sure the injectors are near 100% at max torque/power. This assumes the stock fuel pump can deliver the flow at higher pressure - next thing to check... For that matter the existing pink tops I had reconditioned for the current engine would also work if the fuel pressure was increased 15-20%. Pretty sure the S50 runs 3 bar fuel pressure - the US S50 is supposed to run 3.5 bar (not sure why as it makes crap power that doesn't need the increase in pressure). This suggests increased fuel pressure won't be a problem. Also, the S50B32 Euro is supposed to run 5 bar so again, the injectors must be rated ok for a small increase in operating pressure. One of the local guys here is making 316HP from a M52B28. I suspect somewhere between 320-340 is possible from a M50B31 with similar mods. We're both using the same tuner (and Link ECU) and learning from each other as we leap-frog each other on subsequent mods/tunes. The guy with the 328 is also considering making a M50B30/31 too to see what is possible. Will check MSEL but hope I can work with the standard injectors I already have. 1 Quote Share this post Link to post Share on other sites
Forrest 35 Report post Posted November 7, 2021 ^ I am building a similar engine to yours with closer to OE spec cams for the first iteration and came across these: https://www.bimmerworld.com/Bosch-24lb-Fuel-Injector-Set.html they still might not be enough in your case. Quote Share this post Link to post Share on other sites
