» Site Navigation | | » Recent Threads | | looove 04-16-2024 01:18 PM 04-16-2024 01:18 PM 0 Replies, 1,956 Views | | | | | 08-12-2014, 12:32 PM | #1 | Junior Member Join Date: Aug 2014 Location: Metro Detroit Posts: 3 | Noobie 318ti turbo questions Hey all, I just purchased a '96 318ti with a blown headgasket and I'm looking to fix her up into a fun daily driver. In the long term, I'm already working on a wild swap project so in this car I'm sure I'll be content with ~250whp. There's a junkyard near me with an E36 M42 with 150k on it for $400 or $350 with core, so I'm about to pick that up. At first I was looking at S50 or M52B28 swaps, but after looking at dynos you just don't get very much power for the weight you add to the nose of the car. To reach my goals, I was looking at getting an evo3 16g turbo since it's a small turbo with a tall compressor map good for making power on small displacement motors, ARP head studs, and a cometic 3mm MHG. First off, I'm not sure which route to go with the manifold. I was thinking about getting an M43 cast stock manifold off the UK ebay and flipping it, then having an adapter welded. The OBX manifold looks great, but have they changed it from ~2009 when those build threads with it were posted? It looks like it mounts the turbo too damn low for me, the oil drain from that location wouldn't be acceptable, IMO. There's a few local fab shops that can make manifolds, but it's added time and expense. Next, what to do about EMS? Are the OBDI or OBDII ECU's reasonably tunable, or should I head straight for megasquirt or AEM? OEM drivability would be nice, but I don't want to run a generic "turbo" tune and blow the motor from running a tune for a totally different setup. Do piggybacks like the SAFC work alright on OBDI ECU's? Thanks guys | | | 08-12-2014, 06:32 PM | #2 | Senior Member Join Date: Dec 2007 Location: Gulfport, Florida Posts: 3,208 | SWIM, I would suggest two items.. First use a BMW diesel head gasket and second use M3 head bolts that are shortened for the M4x motor. These items are proven on Metric Mechanic's motors. They have had a few head gaskets fail and so far I'm the only one to blow the diesel gasket with a 29psi boost on pump gas which lifted the head off the block. Contact Barrie at Midnight tuning or I can help you with tuning 100% with no piggy backs or major changes to get a excellent tune | | | 08-12-2014, 07:14 PM | #3 | Junior Member Join Date: Aug 2014 Location: Metro Detroit Posts: 3 | John, could you provide me with a part # for the diesel headgasket? I had seen references to it, but the bmw 4cyl diesel headgaskets I have seen appear to be shaped differently from those for the M42/M44 engines. Also, how much does that headgasket drop the compression on a stock motor? As for the bit about the fasteners, I can get ARP hardware at decent prices, and I prefer a stud and nut to a SHCS for holding the head on. I have seen people use standard grade 12.9 fasteners as well... any particular reason you prefer cut down M3 bolts? I'd really rather not go cutting up and rethreading the ends of fasteners, it seems like you'd potentially trash the threads in the block or at the very least wreck the rolled threads and possibly heat treat at the end of the fasteners. | | | 08-15-2014, 07:59 PM | #4 | Junior Member Join Date: Aug 2014 Location: Metro Detroit Posts: 3 | Anyone know if there's a place I can buy this flange? I'm probably going to have to just trace a gasket and have it cut on a waterjet :/ things are coming along though, I picked up an M42 and started tearing into it yesterday. still need a part # for the diesel headgasket. also, in RealOEM when it lists "0 LOCH", "1 LOCH", and "2 LOCH" on different variants of the headgasket, wtf does that mean? they look like they're different thicknesses, but "loch" means "hole" in german according to google. | | | 08-21-2014, 04:05 PM | #5 | Senior Member Join Date: Dec 2007 Location: Gulfport, Florida Posts: 3,208 | Quote: Originally Posted by SomeoneWhoIsntMe John, could you provide me with a part # for the diesel headgasket? I had seen references to it, but the bmw 4cyl diesel headgaskets I have seen appear to be shaped differently from those for the M42/M44 engines. Also, how much does that headgasket drop the compression on a stock motor? As for the bit about the fasteners, I can get ARP hardware at decent prices, and I prefer a stud and nut to a SHCS for holding the head on. I have seen people use standard grade 12.9 fasteners as well... any particular reason you prefer cut down M3 bolts? I'd really rather not go cutting up and rethreading the ends of fasteners, it seems like you'd potentially trash the threads in the block or at the very least wreck the rolled threads and possibly heat treat at the end of the fasteners. | I will have to look up the gasket number on a old one I have in the shop, might take a day or two (Shop looks like a tossed salad. The head gasket is thick but I don't thing it drops it more then .5 or maybe even less. With any boost the lower the compression the better, I run 8.5:1 and my motor run real good, I really can't tell the drop in compression from the stock compression. It's your motor and ARP studs could be just fine, I have not tested them or know of anyone running them on a boosted M4x. I don't know torque on a ARP head stud kit so you will have to figure that out. The M3 bolt idea is from Metric Mechanic. The bolts are a direct replacement that can be used again if you need to remove the head, they are not like the stretch bolts like OEM stock. The shank is much thicker then the ARP studs. Metric cuts off a few threads so you can torque them to 68ftlb. The bolts cut look exactly like a stock bolt so I guess they roll threads or whatever you are talking about. I just go with what has worked for me for 3-4 years now. Best, John S | | | 08-22-2014, 04:35 AM | #6 | Member Join Date: Aug 2014 Location: MA Posts: 41 | How much boost can a stock engine take? | | | 09-03-2014, 02:44 AM | #7 | Senior Member Join Date: Dec 2007 Location: Gulfport, Florida Posts: 3,208 | Quote: Originally Posted by bmwme How much boost can a stock engine take? | With a good tune 15-17 psi daily. I dogged the $hit out of a M44 for 76K miles then used that motor as a core. That motor had approximately 180K total miles when I used it as a core. The shop (Metric Mechanic) said that core was in very good condition with miles left on it. My opinion: Major factors that destroy turbo M4x motors. 1st and the main reason most of these motors "self destruct" is incorrect tuning or a bad tune including injectors that can't flow enough fuel for the additional air being packed into the motor under boost. 2nd is the "Money Shift", stock rotating assemblies on the M4x are ok but don't like the very high RPM that happens during the money shift. Also stock valve springs can "float" during the money shift causing the piston to contact the valve. That is about all I know about issues and max boost for the stock motor. Maybe some other members can add to the list of issues. I've been lucky and have not had too many issues running high boost. Best, John S | | | | Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | | Posting Rules | You may not post new threads You may not post replies You may not post attachments You may not edit your posts HTML code is Off | | | |