325_driver 422 Report post Posted September 16, 2007 Since im chucking my engine in a different shell i thought i might aswell do other things to it aswell e.g. i am getting a lsd for my e30 325i etc Wondering whether i could get a boost in hp by chucking some bigger injectors on it maybe 328i injectors ? or 535i injectors ? Im no car mechanic and usually have no idea when it comes to the logic or factors so Am i wasting my time looking into this? or are there any easy (ish) things i can do to increase the amount of fuel intake then i can look into the induction side of things Any thoughts cheers Quote Share this post Link to post Share on other sites
bravo 35 Report post Posted September 16, 2007 Your stock injectors are more than you need for a stock motor. What you need to focus on is getting more airflow and removing the exhaust gases. The computer will compensate by adding the extra fuel needed and the injectors will handle it. Quote Share this post Link to post Share on other sites
325_driver 422 Report post Posted September 16, 2007 thanks for that, my dad is already making a set of extractors and were designing a custom exaust. what could be done about air intake? Cold box with k&N filter? thoughts Quote Share this post Link to post Share on other sites
hybrid 1043 Report post Posted September 17, 2007 yeap ... that will be a nice start Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted September 17, 2007 actually, 2.5 m20 injectors run leanish even at stock hp rates...start going up and they lean out more read up on e30tech.com and r3vlimited.com, they have done a lot of playing around. might not really be worth it however Quote Share this post Link to post Share on other sites
bravo 35 Report post Posted September 17, 2007 (edited) There's alot of rumour and myth being bandied about Gus. My personal feeling is that most of the problem is that people are running worn 20yo injectors that are all clogged and carbonned. They upgrade the injectors and the car performs better. I have a hunch that most of the time if they replaced them with new stock ones they'd see the same improvement. I'm only speculating based on the research I've done lately on megasquirt and supercharging. You don't need to go much bigger for the s/c, and the flow rate specs of the stock bmw injectors aren't too low for very low boost (just nothing in reserve). Unless you plan on squeezing a fair bit more power out of the motor by doing other mods like stroking or FI, then bigger injectors prob won't help. Replacing your old ones with new ones might though, and if there is no price difference, then there should be nothing wrong with going bigger. just keep in mind that your l/100km gauge may not read correctly with diff injectors. Edited September 17, 2007 by bravo Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted September 17, 2007 injectors do need to have some headroom however, they arent really designed to run at 95% duty cycle like the stock ones seem to. i could be wrong here however as it has been a while! you could be right about the age of them too. personally, i really wouldnt bother mucking around with minor power mods..they cost far to much for the actual gain you get out of them Quote Share this post Link to post Share on other sites