wrs 120 Report post Posted February 11, 2016 (edited) Due to a few changes since my car was originally tuned I need to get it re-tuned on the dyno again. It's not running right any more with a few flat spots and it doesn't sound or feel right above 5k RPM. The 2 changes are new bigger exhaust and getting the Vanos fixed so it works properly. It's possible the valve timing is slightly different now too since the Vanos was removed and refitted. The original build is here: http://bimmersport.co.nz/topic/53887-e36-325i-coupe-project/ During the original dyno tune it was discovered the 325 green injectors ran out of putt above 6k RPM. So, since I'm going to get a re-tune I may as well do the injectors just prior... I have the M50B25 Non-Vanos manifold so need injectors that will fit. There seems to be very little info about which injectors fit which manifolds. So, does anyone know which injectors will fit the manifold I have? (do all M50/S50/M52/S52 injectors fit the same manifolds?) There also seems to be a little confussion over which injectors have which flow rates and there seems to be a few different colours available. Green (325, seems to be some S50's (maybe US)) Pink (is there more than one type) Light Blue?? Dark Blue?? M54 Injectors??? Which is which? Does anyone have suitable injectors to sell? Edited February 11, 2016 by wrs Quote Share this post Link to post Share on other sites
Ahmedsinc 414 Report post Posted February 11, 2016 M54B30 injectors (purple top) will work with an M50 fuel rail but the rail needs modification as the injectors are shorter than the green tops. M52B28 ones might be closer to your required fuel rate - maybe use those with a rising rate FPR? Should keep the injectors at the same duty cycle but with the increased rail pressure it might be enough to stop you leaning out. Probably not the best solution but probably the easiest? Quote Share this post Link to post Share on other sites
thorburn 121 Report post Posted February 11, 2016 You just want some top feed injectors. Some need adapters but the majority are what you've got. Also you'll probably want high impedance injectors. If you give your tuner a call they should be able to tell you exactly what to use. For injector info I usually use the witchhunter website.http://www.witchhunter.com/injectordata1.php 1 Quote Share this post Link to post Share on other sites
wrs 120 Report post Posted February 11, 2016 Fantastic, thanks for that link. It helped confirm the 0280 150 440 pink injectors are what I should use. I think I can get a set of these off the M52B28 donor engine I have for the Vanos conversion on the M50B25nv. Should probably have used these to start with... I was sitting on the right injectors all along!!! Cheers!! 1 Quote Share this post Link to post Share on other sites
wrs 120 Report post Posted March 5, 2016 The pink-top all in good shape. I had them tested at DSL and all injectors were between 206-208cc @ 3 Bar so a very good result. DSL also replaced the filters, O-Rings and plastic ring thingy at the bottom so they're ready to install. I have to wait until after middle of the month for he re-tune though (monthly salary)... One thing I have noticed on the few cooler days we've had recently is the car goes a lot better and sounds a lot better than hot days. Driving to work in the morning is nearly always better than coming home too. I'm wondering if the inlet air temperature correction map could be off a bit. As the temperature gets up round 30'C is where it starts sounding and feeling a bit off. 15-20'C isn't too bad (still needs a retune). I'm wondering if the temperature compensation is not quite right. Maybe this is normal on NA engines?? Quote Share this post Link to post Share on other sites
polley 916 Report post Posted March 5, 2016 Likely to be retarding timing with higher iat's. Friends high comp m52b28 we tuned is the same, street tuned it on gull force pro on a cold night, run it on anything else or if ambient temps are high it loses a lot of power. Quote Share this post Link to post Share on other sites
