In reply to z31maniac :
I seem to remember perusing some e46 forums and coming across that number, but maybe I misunderstood and that was actually the OD for the purpose of plumbing their intake hoses or something.
You've certainly got a point though. I guess it'll all come down to what engine I can find and at what price. The junkyards by me seem to get cars with the 3.0 liter M54B30 relatively frequently, but I may have to wait for a sale since I'd need the full harness, ecu, mounts from a different engine, and a throttle pedal assembly.
Having never run a restrictor on an engine, I'm just nervous and hesitant to force the ECU to do a lot of compensating. However, I also know nothing, so maybe it would be fine haha
I think it’s gonna be tough to find a non-vanos (or otherwise) M50 these days. But hey, you never know. Just not sure it’s worth holding out for.
And yeah the non-vanos M50 is really peaky in my experience, like an old VTEC feel.... not much power until in rips at 4k-ish to redline. Maybe not an issue on the track, but on the street I would sometimes have a problem outpacing much slower cars on an on ramp. This was with a Conforti chip too. The later m52 was much fatter down low. I did like how the early engine ripped hard up top though.
artur1808 said:
In reply to z31maniac :
...and a throttle pedal assembly.
True, the M54 goes to drive by wire. That is something to keep in mind for the swap. Seems like you already thought of that though.
At this point I've collected the majority of parts that are shared among the m5x series of engine swaps (oil pan, dipstick tube, trans crossmember, "twisted" dssr, and Porsche 944 brake booster). So the simplest solution would be to buy an e34 so I can drop it right in and have an extra oil pan. M54 would require a new oil pickup tube, throttle pedal mounting, and ECU reprogramming to delete the EWS system. Both will require headers, wiring, and heater core plumbing.
The purpose of this thread originally was to try to understand why there seemed to be a dip in power for the M52 series of 2.5l engines, but at this point since we are getting into the swap details, I'm open to hearing other opinions.
You could always just do an S50/S52. No worries about DBW and both are basically M50/M52 with an extra 0.5L of displacement and hotter cams.
My S52, with OBD-I manifold, 3.5" Porsche MAF, TMS headers, tune, and 2.5" exhaust all the way back put down 235/235 at the wheels in my E30 10 years ago.
In reply to artur1808 :
One last bit on the swap details, the ECU programming to delete the EWS system I don't think should be very hard. My buddy has a laptop setup to do it, and got me the stuff to set one up too. I haven't gotten into it yet, but it shouldn't be that hard.
As far as the power dip for the M52s, I have no idea. Sorry.
Ah yes my knowledge on 90s bmw engines finally comes to use. BMW came out with the M50 in 92, this was a no variable valve timing engine. in 93 they came out with m50tu, which had single vanos on intake cam, which varied cam position with oil pressure. was an on-off switch. M50 continued until 96, when m52 came out. M52 is just an obd2 compliant m50 pretty much everything is exchangeable. Due to emissions regulations m52 has a little less power. (different intake manifold, vacuum system, exhaust manifold, etc) It is actually a popular swap to put the old m50 intake manifold on the m52, opens it up quite a bit! best bang for buck in e30 id say is m50tu-vanos makes up for the hotter cams that non vanos has IMO
If I remember right the 2.5 M52 went in the 323i, which was the new entry-level 3 series, replacing the 318i. They couldn’t have it be as powerful as the outgoing top shelf 325i (which had been replaced by the 328i with a 2.8 M52) so the engine produced less power. Emissions may have been involved, but my my guess is that they purposely restricted output to put it below the outgoing 325i and not crowd the new 328i. They did this again with the E46 if I recall correctly.
This is my conjecture and based on 20 year old memories, so take it with a grain of salt.
artur1808 said:
In reply to z31maniac :
I seem to remember perusing some e46 forums and coming across that number, but maybe I misunderstood and that was actually the OD for the purpose of plumbing their intake hoses or something.
You've certainly got a point though. I guess it'll all come down to what engine I can find and at what price. The junkyards by me seem to get cars with the 3.0 liter M54B30 relatively frequently, but I may have to wait for a sale since I'd need the full harness, ecu, mounts from a different engine, and a throttle pedal assembly.
Having never run a restrictor on an engine, I'm just nervous and hesitant to force the ECU to do a lot of compensating. However, I also know nothing, so maybe it would be fine haha
Restrictor will be fine. No worse than all the people that never change their air filter and run with stupid amounts of pressure drop across the filter.
Factory does a pretty good job of troubleshooting "out-there" failure modes. :)
artur1808 said:
In reply to irish44j :
Yeah, but I figure getting rid of stuff will offset some of the lighting and huge skid plate.
Entire A/C system removed, no power steering, currently removing the ABS pump/distribution block thing. Then some smaller stuff, like my car never had a windshield washer bottle so I just bought a generic amazon one that I'll probably mount farther back than factory, I removed the factory hood hinge mechanism when I installed hood pins, etc. None of which are going to be a huge savings, but I figure that if nothing else it'll offset some of the weight that has to get added back in with rally reinforcements and lights.
edit: will post this stuff in your build thread, so as not to clog up this one.
CyberEric said:
I think it’s gonna be tough to find a non-vanos (or otherwise) M50 these days. But hey, you never know. Just not sure it’s worth holding out for.
It's not that tough if you' specifically search for cheap e34s on CL or facebook marketplace. People are forever unloading those for near scrap-value (and they already have the right oil pan). I think I found three of them for under $1k when I did my swap (some were VANOS, some weren't - I ended up changing my mind and getting VANOS for its advantage of lower torque, which is useful in rally).
The other downside to going with an M54B30 (or m5xB28) is that anything over 2.7 liters would bump me out of "limited 2wd" class and into "open 2wd" class for ARA and I'd really prefer to start out in Limited 2wd.
So I guess the primary discussion should really be M50B25 (vanos or non-vanos) vs. M54B25 since the M52 has less power than the others and offers no benefit as far as I can tell. The m50 is certainly easier, especially if I find an e34 so I have an extra oil pan. The m54 is more "future-proof" if I decide to make the jump to "Open 2wd" and get some more power down the road, but is a more involved swap.
artur1808 said:
The other downside to going with an M54B30 (or m5xB28) is that anything over 2.7 liters would bump me out of "limited 2wd" class and into "open 2wd" class for ARA and I'd really prefer to start out in Limited 2wd.
So I guess the primary discussion should really be M50B25 (vanos or non-vanos) vs. M54B25 since the M52 has less power than the others and offers no benefit as far as I can tell. The m50 is certainly easier, especially if I find an e34 so I have an extra oil pan. The m54 is more "future-proof" if I decide to make the jump to "Open 2wd" and get some more power down the road, but is a more involved swap.
Bumps you to open if you DON'T use the restrictor, correct? Or is the restrictor for for over 2.7 just "Novice" or "Not Novice"
I'm not sure why you're so against using one, it's not going to hurt anything. But it sounds like you have your mind made up, go with the VANOS it noticeably fattens up the midrange.
In reply to z31maniac :
Bumps me to open regardless of Novice status. The restrictor is just for "Novice" vs. "Not Novice". At this point, I'm not against using the restrictor. The comment above of it being no different than a particularly dirty air filter made a lot of sense to me.
I am certainly keeping an open mind. What I'm looking for now is really feedback/experience from people who have run an e30 with an M50 or M54 and whether the perceived advantages of a newer Vanos engine are worth it. Specifically on gravel/snow. The torque does sounds nice, but I'm wondering if there's a point of diminishing returns?
I'm not going to add much more than the wisdom already dealt in this thread. (It still amazes me how much knowledge is present here.)
But here's my contribution: I race an E36 with an M50B25TU. I've used the same engine for close to four years through two race cars, and overheated it pretty badly on track once (through my own stupidity) and it has been an absolute tank.
I also race with a friend who has the M52B25 in his car (it's a 323i). I make just about 180 on the dyno with no engine mods except a cone filter and straight pipe exhaust. He makes 163 peak on the dyno. I'm not sure exactly what modifications he's running but it certainly can't be less than what I have lol.
Also totally agree with the chorus of "don't be afraid of the single vanos." I'm rebuilding the vanos system on an M62 V8. That's a chore. the M50 is not nearly as bad.
Also side note: I do have a spare M50B25TU laying around. I'm not sure where you are but it's here already pulled. I haven't done anything more than pull the valve cover off and it's pretty gummed up, but It drove around perfectly before I pulled it.
artur1808 said:
In reply to z31maniac :
Bumps me to open regardless of Novice status. The restrictor is just for "Novice" vs. "Not Novice". At this point, I'm not against using the restrictor. The comment above of it being no different than a particularly dirty air filter made a lot of sense to me.
I am certainly keeping an open mind. What I'm looking for now is really feedback/experience from people who have run an e30 with an M50 or M54 and whether the perceived advantages of a newer Vanos engine are worth it. Specifically on gravel/snow. The torque does sounds nice, but I'm wondering if there's a point of diminishing returns?
Gotcha, that makes things more clear. I would base the choice of engine on this:
Do your future plans involve moving to Open at some point or staying in Limited? If at some point, you want to move to Open, go ahead and get your engine of choice, run the restrictor and start racing!
The M52B25 and M50B25 are pretty much identical as far as longblocks go.
The intake and exhaust manifolds are different but swappable between them.
M50/S50 motors had OBD1 electronics/wiring and less restrictive intake manifolds but more restrictive exhaust manifolds.
The M52/S52 motors had OBD2 electronics/wiring a choked down intake manifold designed for more torque for the american market and better exhaust manifolds to try to salvage some exhaust flow while saddled with more restrictive obd2 emissions systems.
I can't speak with any actual experience about an M54 in an e30 as the last e30 I 24v swapped was when the dual vanos M54 stuff was considered black magic. However my S52 e30 could easily spin sticky 200tw tires at any speed in the first couple gears so i'd think an M50 would be sufficient power?
The M50b25 comes in both a vanos and non vanos variety. I'd personally skip the non-vanos option, you're doing all the same work of a 24v swap, oil pan, wiring, etc. without the added torque gain and really backing yourself into a pretty small corner as far as spares/replacements go. The beauty of a 24v swap with any of the other vanos having m50/m52/s50/s52 variants is that once you've done the swap more power is just a longblock swap and new ecu chip away should you someday move to open.
In your shoes I would purchase whatever m50/m52 b25 longblock you find at the best price/location/value to you and then run the obd1 intake manifold with your choice of headers or obd2 exhaust manifolds. For wiring you could go obd1 or 2 whichever you prefer, I like the obd1 wiring because you don't have to deal with EWS issues and trying to match keys to computers etc. however having obd2 functionality does make troubleshooting easier once the swap is up and running.
I would think the added complexity the m54 swap brings along with a dual stage intake manifold etc are just more failure points for a car that will see some fairly rough conditions. so from that standpoint I'd stick to the e36 family of motors.
I’ll add that some years ago I read up on an internal swap for the M50 that was a budget stroker. I don’t remember the details but I think it was something like the crank from a 330i and pistons from something else. This might be an affordable options for more power in the future if you decide you want it.
I thought m52 blocks were aluminum, am I nuts?
Robbie said:
I thought m52 blocks were aluminum, am I nuts?
Only the Z3 blocks, IIRC.
spandak said:
I’ll add that some years ago I read up on an internal swap for the M50 that was a budget stroker. I don’t remember the details but I think it was something like the crank from a 330i and pistons from something else. This might be an affordable options for more power in the future if you decide you want it.
Yep, there are a lot of different combos like this.
The M20/M5x/S5x engines all share the same bore spacing.
That's why with the right crank nose spacer you can use an 89.6mm crank and overbored pistons to make a 3.1L M20.
artur1808 said:
The other downside to going with an M54B30 (or m5xB28) is that anything over 2.7 liters would bump me out of "limited 2wd" class and into "open 2wd" class for ARA and I'd really prefer to start out in Limited 2wd.
I wouldn't worry too much on that account. most of the e30s run in Open anyhow (though my car *technically* can probably squeeze into Limited if I want to). Open means you get to run against fun things like Mk2 Escorts, Merkurs, most of the other BMWs, etc. Limited means you get to run against a swarm of FWD Fiestas and stuff, lol.
In truth, speed-wise it doesn't much matter. Open isn't appreciably faster than Limited in the regional entries (national entries are a different story).
Long and short of it is - don't make build decisions on an e30 based on class rules. .
artur1808 said:
In reply to z31maniac :
, but I'm wondering if there's a point of diminishing returns?
The thing I've always heard said for most RWD cars (including e30s) in rally is that 200hp is the line past which "it doesn't matter" for most cars. Sure, some cars can deal with more (Hooper's Lexus is very heavy, but also very powerful), but that's assuming a lot of nice stuff to help you put the power down (like $$$ suspension, diffs, always-new tires, etc).
I'll let you know after STPR what I think , since I'm right around 200hp now (up from 130, which was NOT enough for most large rallies).
irish44j said:
[...] (though my car *technically* can probably squeeze into Limited if I want to)[...]
I thought your car would be pretty firmly in Limited 2wd. What makes it a technicality? Just the issue of your car being a 318 and the motor only being available in 325's?
artur1808 said:
irish44j said:
[...] (though my car *technically* can probably squeeze into Limited if I want to)[...]
I thought your car would be pretty firmly in Limited 2wd. What makes it a technicality? Just the issue of your car being a 318 and the motor only being available in 325's?
There is some rule mushiness out there, as I read them. I mostly just run open because I don't care enough to check. Same reason when I started rally crossing I went directly to MR even though my car was basically stock. Worrying about class rules is for autocrossers and/or people who think they are going to win a championship. I'm neither, so......:)
