Driftit 1948 Report post Posted November 3, 2008 Hey guys I am just about to start building my M20B28 for my worn out 325. I was going to dump a 1jzgte in there but thought I would have more fun from a BMW motor as power is not everything. Thought I would take a crap load of photos and keep a diary of the build for eveyone rather than being secretive like some others who are currently building. Plans so far are to use my current M20B25 motor which has currently got a case of the 300,000kms worn cam shaft and rockers. Other than that she was recently dynoed at 101rwkw on a very tough low reading hub dyno so I am hoping the block and head will check out AOK. Still have to work out which Cam and ECU setup I will use. Any help and suggestions are welcome. My first question is a simple one. Which main and big end bearings do I use? I presume the stock M20B25 Mains and the stock M20B20 Big ends? (M20B25 and M20B20 bearings the same??) Quote Share this post Link to post Share on other sites
Jeddy 0 Report post Posted November 3, 2008 Have you read the few very well documented builds on e30zone? Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 3, 2008 Not on E30zone no. I will read them now. I have read through various others though. Will sign up to e30zone now. Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 3, 2008 Had a talk to Gavin at Hi Velocity and will also be using the facelift loom and ECU which makes things alot easier when it comes to timing and tuning. And my list according to the guys on E30Zone M20B25 head/block/pistons/inlet manifold/injectors/ECU M52B28 crank M20B20 conrods Catcam? 273 degree cam Total seal piston rings Heavy duty grade main and big-end bearing shells New rockers and shafts Spray bar Water pump Main and big-end bolts All new locating dowels Quote Share this post Link to post Share on other sites
Jeddy 0 Report post Posted November 3, 2008 Had a talk to Gavin at Hi Velocity and will also be using the facelift loom and ECU which makes things alot easier when it comes to timing and tuning. And my list according to the guys on E30Zone M20B25 head/block/pistons/inlet manifold/injectors/ECU M52B28 crank M20B20 conrods Catcam? 273 degree cam Total seal piston rings Heavy duty grade main and big-end bearing shells New rockers and shafts Spray bar Water pump Main and big-end bolts All new locating dowels If you can afford it i'd get 272 Shrick cams and valve springs.Also do you have the head rebuild article/write up? Is gavin just tuning the ecu or chipping it? Quote Share this post Link to post Share on other sites
mr E34 11 Report post Posted November 3, 2008 The 2.8ltr seems the way to go now (from 2.7), rapala on Bimmer has just started his 2.8 rebuild. Any idea what sort of pwr/trq they deliver? Quote Share this post Link to post Share on other sites
tire 10 Report post Posted November 3, 2008 Thought I would take a crap load of photos and keep a diary of the build for eveyone rather than being secretive like some others who are currently building. Shot. Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 3, 2008 I will be getting a cam and valve springs. This motor is dead cheap comparied to what I have recently built for my 180sx. From what I have been reading the Poms seem to be getting anywhere between 180 to 250hp. Some of the higher figures of course have extras like manifolds etc. As for the chip or tune. I am not 100% sure just yet. Will have another chat to him when I take my series car in on Monday for its tune up. But I am going to install the Facelift 325 loom and ECU. Quote Share this post Link to post Share on other sites
williams 0 Report post Posted November 3, 2008 all petrol engine bearings are the same size only m3 e36 slightly bigger Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 3, 2008 Cheers mate. Will order them 2moro. As for the Oil Pump. Is there a trustworthy aftermarket part that can be purchased? The genuine ones are very pricey. But if they are the best than I dont mind paying. Quote Share this post Link to post Share on other sites
Jeddy 0 Report post Posted November 3, 2008 m20 head rebuild and valve adjustment write ups incase you or anyone else wants them m20_head_rebuild.doc m20_valve_adjustment.doc Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 20, 2008 Collected all my parts for the motor now. But I have to sort out my series car motor first. Will start in a few weeks with lots of pics etc. Quote Share this post Link to post Share on other sites
tibbs.james 1 Report post Posted November 22, 2008 Which valve springs are you going to run, and where are they from? and since you have recently built a "series" motor did you notice if the 731 head's valve springs are the same as a 325 in overall dimensions?. Good luck with both engine builds. Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 25, 2008 Have not decided on the top end stuff just yet. Most of the gear I have looked at is all from the states. And with the current exchange rates it is all very pricey. But most of the stuff I am looking at is from Ireland Engineering. Such as the heavy duty rockers. But they are $25US each. Unsure on the valve springs as yet. Having a hard time finding them. And sorry I did not build my 320's head. Was done by someone else. Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted November 27, 2008 After hunting around for hours and hours with no luck in finding much for the head I wish to build, I sent an email to Carl Hayman at www.engineparts.net.nz who has helped me previously for hard to get bits and pieces. They have everything avalible. So will pop in and see them and they will help me match up what I need. Will post the details once I get time to go in. Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted December 9, 2008 Hey guys. Just a quick question. A reground brand new billet cam for $480 inc a good price? From Kelfords. They supply the billet? Sounds good to me. Also have been looking at these rockers from Ireland Engineering. http://store.nexternal.com/shared/StoreFro...et=products.asp But do you think they are really necessary. I am only doing slight head work at this stage. They are pricey at $25 US each. Bumping just over $600NZD for a set. Ouch. But they are 1/4 of the price of solid billet alloy ones. Quote Share this post Link to post Share on other sites
Andrew 30 Report post Posted December 9, 2008 Hey guys. Just a quick question. A reground brand new billet cam for $480 inc a good price? From Kelfords. They supply the billet? Sounds good to me. Also have been looking at these rockers from Ireland Engineering. http://store.nexternal.com/shared/StoreFro...et=products.asp But do you think they are really necessary. I am only doing slight head work at this stage. They are pricey at $25 US each. Bumping just over $600NZD for a set. Ouch. But they are 1/4 of the price of solid billet alloy ones. avoid the Ireland rockers.. honestly. In fact, avoid nearly everything from IE! Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted December 9, 2008 ^^ more...for some reason can't stop thinking m20 stroker.. Quote Share this post Link to post Share on other sites
Driftit 1948 Report post Posted December 9, 2008 Ok well the ireland rockers are the only ones that are in my price range so I wont be getting any. Just stock ones. What is wrong with the ireland engineering stuff though. I know quite a few people using various items. No complaints so far. And their prices are pretty good conpaired to what you can get here. Quote Share this post Link to post Share on other sites
Guest SamSpargo Report post Posted December 9, 2008 ^^ more...for some reason can't stop thinking m20 stroker.. With a snail? Low comp 2.9 goodness? Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted December 9, 2008 haha no..was more an N/A low power idea, with torque..just a stupid one sam, and you know why! Quote Share this post Link to post Share on other sites
Guest SamSpargo Report post Posted December 9, 2008 Because 2 cams are better than one. Duh Quote Share this post Link to post Share on other sites
