antony 0 Report post Posted November 18, 2007 (edited) As some of you know, I'm starting a 2.7 build (using the 731 head). At the moment I'm collecting all the parts. I'm planning on getting a performance cam than f**k around with 325i or 323i cams. It'll be a cat cam like this. I'll also be getting a 2.7 chip from the UK. I'm just a bit indecisive about what duration to get. It'll either be 273/273 or 283/283. So could some of the techies who have experience with this please advise me on the advantage and disadvantage of both. Cheers Antony. Edited November 18, 2007 by antony Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted November 18, 2007 probably the 273....my understanding of cams is that in the m20 they dont produce a great deal of power, however they move the powerband...your 731 head should be a bit of a torque monster so aim for the lesser duration to get the benefit down lower. i imagine either cam would work well however i could be all wrong...have read in TBMW (yes, i know they are always wrong) that one guy got 190ish hp with that build, 325i manifold and injection etc and a decent cam..cant remember the duration Quote Share this post Link to post Share on other sites
boydusM325i 0 Report post Posted December 14, 2007 As some of you know, I'm starting a 2.7 build (using the 731 head). At the moment I'm collecting all the parts. I'm planning on getting a performance cam than f**k around with 325i or 323i cams. It'll be a cat cam like this. I'll also be getting a 2.7 chip from the UK. I'm just a bit indecisive about what duration to get. It'll either be 273/273 or 283/283. So could some of the techies who have experience with this please advise me on the advantage and disadvantage of both. Cheers Antony. Hi Antony, Hows the 2.7 build going? Did you sort out what cam your going to run? Either one of the sizes you described will net you a good gain with the larger capacity providing you raise the compression ratio to around the 10.0:1 mark. Im running the 288 schrick in mine and getting 215hp. Of course I have made other mods to the engine to achieve this.. Let us know how you get on! Boyd. Quote Share this post Link to post Share on other sites
antony 0 Report post Posted December 14, 2007 Hey. I'm just at the tail of getting all the parts. I've ordered a 273/273 catcam and a 2.7 chip from ant woodjetts (in the UK). I'm picking up an inlet manifold, AFM, throttle body, injectors, fuel pressure regulator, from a 325i at new years. I've sourced a 525e engine and already have the head off it. Am thinking of getting another 731 head, rather than use mine, because I can then sell my engine and gearbox as a whole. It's only got 125k's on it. I've swapped my getrag 240 i had for a 260 (It's getting converted to manual at the same time), and swapped my 4.1 diff for a 3.64. Will be looking to get it built late January. All the parts mentioned above, including the gearbox and diff, have cost $2255 so far. Hopefully wont cost much more to have built, have to save for uni next year to. Have considered doing it myself with the head mechanic from work, but I want it done right. Will have it dyno'd and tuned upon completion, and will hopefully give others an idea of the power to expect. (I seem to hear alot of different stories, probably from different spec 2.7's. Is that 215hp at the flywheel? Your running the 885 head IIRC. What compression ratio have you got? Mine should be the same as the original motor as the heads are the same shape. Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted December 15, 2007 Hey. I'm just at the tail of getting all the parts. I've ordered a 273/273 catcam and a 2.7 chip from ant woodjetts (in the UK). I'm picking up an inlet manifold, AFM, throttle body, injectors, fuel pressure regulator, from a 325i at new years. I've sourced a 525e engine and already have the head off it. Am thinking of getting another 731 head, rather than use mine, because I can then sell my engine and gearbox as a whole. It's only got 125k's on it. I've swapped my getrag 240 i had for a 260 (It's getting converted to manual at the same time), and swapped my 4.1 diff for a 3.64. Will be looking to get it built late January. All the parts mentioned above, including the gearbox and diff, have cost $2255 so far. Hopefully wont cost much more to have built, have to save for uni next year to. Have considered doing it myself with the head mechanic from work, but I want it done right. Will have it dyno'd and tuned upon completion, and will hopefully give others an idea of the power to expect. (I seem to hear alot of different stories, probably from different spec 2.7's. Is that 215hp at the flywheel? Your running the 885 head IIRC. What compression ratio have you got? Mine should be the same as the original motor as the heads are the same shape. a freind of mine has head for sale . 021433600 Quote Share this post Link to post Share on other sites
antony 0 Report post Posted December 15, 2007 (edited) thanks, but I will have a look in the south island 1st. Edited December 15, 2007 by antony Quote Share this post Link to post Share on other sites