So the plan was to rebuild a motor for my dd, and I figured I would upgrade while I was at it.
I picked up an m52(b28) awhile ago with 150k on it. Then I heard about the m54 3.0L upgrade/stroker thing
I picked up an m54(b30) for free from a local club member who hydrolocked it a year ago. The externals and inside the head and crank area were spotless clean for an engine with just over 100k. It was at low rpm when it stalled, but the PO did the worst thing possible, and tried to restart the engine. Long story short, the engine was locked up by the time I got it. Upon removal of the pistons, 2 of the rods are obviously bent. So using the entire rotating assembly is obviously out.
So here is what I have.
M50b25 complete
m50b25tu (in the car and running)
M52b28 short block
M54b30 with bent connecting rods
What's my best bang for the buck ?
I do plan on keeping the vanos...
Also, I would like to add, if you have no clue what you are talking about, please read and enjoy and learn something, but for God sake, don't post. Sorry if this sounds harsh, but there are good threads out there with misleading info, and the same question about 100x. Thanks.
And here is where things go terribly wrong...
I wanted to say also that I have done a bunch of research, and have read a shitton of threads.
I know all 4 engines I have are 84mm bore, I know the cranks have all different strokes, 75mm, 84mm, and 89.6mm. I know the tu motor has 140mm rods (thanks Jon) and the others have 135mm. My issue is I don't know enough about the piston length or C/R.
Last edited by WhoNew; 04-23-2012 at 12:47 AM. Reason: Automerged Doublepost
i would imagine m54 crank with m52 rods and pistons
or if that didnt work out, m54 crank and pistons, m52 rods
id confirm the figures, conrod lengths and piston dims and work out whats what, but as bmw seem to consitantly use the same length rods id be will ing to bet you could go the above route
I always thought m54's 3.0 had larger bore (but thats only what i thought)
stick with a single vanos head to keep things simple for management IMHO.
Long time E34 owner
Now E39 530D touring Sport Auto
I have a set of m54b30 rods if you are interested.
P/M me and we can talk.
Dammit now I want an m54 crank for my build!!!!! Thanks alot!
ha
same here now lol
Long time E34 owner
Now E39 530D touring Sport Auto
The m54 pistons are trashed too. Honestly, I would think the m52 rods and pistons and block are the way to go. I'll end up pulling the m52 crank and dropping the m54 crank in it.
So basically it looks like
M52 block
M52 rods and pistons (new rings and block hone)
M54 crank
I have no idea about C/R with that setup, and have read the pistons will need to be shaved down 4mm, but Idk if that's true or not
You have probably seen this thread. Every possible question has been asked about stoker combinations.
http://forums.bimmerforums.com/forum....php?t=1715145
Only M54 pistons work with an M54 crank, everything else will stick outta the block iirc...
Well that's the rub.
And yeah, every question has been asked and answered, but answered differently about half the time. So now I need piston dimensions and wrist pin to top of piston dimensions for all 3 series of engine, and center of crank to deck height dimensions on all 3 blocks.
No m54 dimensions but M52 and M50...
http://84.45.115.78/e30zonewiki/inde...M50#Components
Might be some info in there...
what you could do is either get custom rods or pistons according to the height and CR you want, if you already run your car on premium juice a slight bump in CR won't hurt. However having pistons sticking out the top of the block is obviously a no go.
Personally, I would just go with m52 block, M50TU head and S50/52 cams... A lot of people are doing it and it's tried and tested. You're not gaining all that much displacement with the M54 internals over the M52 short block anyway, something like 19cc?
huh? i thought somone said m52 and m54 were the saem bore? (although i thought not)
so how can you not gain hte full 0.2 litres??
Long time E34 owner
Now E39 530D touring Sport Auto
M54 pistons, crank and connecting rods into the M50 would be perfect, giving you a 3.0l engine, add a M3 DME and you are done.
But if the rods and bent and the pistons are damaged... then you end up with the M54 crank M54B30 crank = S52 crank (forged).
I am thinking about doing the same for the wagon turbo engine:
M50NV with M54B30 crank, connecting rods and forged 8.5:1 comp. pistons
Last edited by Frchdragon; 04-24-2012 at 09:18 AM.
Webmaster of: www.bmwe34.net
'85 635csi Race car M30 turbo, megasquirt, FMI
'92 525i Touring, 5 speed UUC flywheel and M5 clutch, SLS
Because the M54 isn't actually 3l... Nor is the M52 2.8... They're both just close
M50, m52 and m54 are all 84mm bore.
Is the M50TU head that much better than the M52 head? I was planning on just having the M52 head mildly ported but if getting the M50 ported and re-using it would be even better.... Problem is I am pretty sure the valve train is pretty damaged after the over-rev on the M50 so I would prob need new valves/lifters/springs which could be expensive...or could I use the M52 stuff in the M50TU head? SOO MANY QUESTIONS!!!! ARRRRG!.
I was specifically referring to WhoNew's options, the best head he has is the M50tu, the best bottom end he has is the M52b28 so I reckon he should go that route!
To my knowledge the M52 and M50 heads are the same basic casting but the M52 has better valve train (lighter & stronger) and especially in your case
So I would definitely use your M52 head and by all means get it ported. You probably don't need me to tell you this but use your M50 intake manifold, much, much better flow!
Cliffs: Use the M52 head (ported ) and M50 intake mani
That link has epic info. Thank you.
Yeah it's pretty sweet! Good luck with your build man!
OK that was what I thought and my original plan.Originally Posted by NedMW
m50 and m52 heads are identical except the m50 has an additional coolant sensor hole
the fittings in the head may well be different however
So the m52 valve train is better? any details? i was jsut going to put a complete m50 head on my m52, but i do have the complete cams and trays i could throw in if thats preferred... i skipped the valves with the old head however...
Long time E34 owner
Now E39 530D touring Sport Auto
From what I've heard the M52 valve train is, but I haven't done any research on it... I'd just google it and see what's what...
Okay, as far as I can tell, the block from center of crank to top of block is 211mm
So from 211.14 we subtract the rod length, the stroke, and the piston ( from center of the wrist pin to top of piston)
135+
89.6 (/ by 2) 44.8
31.82= 211.62
The m54 piston is on the right, the m52 on the left
The m54 piston is 4mm shorter.
So now I am thinking about using the stock m54 pistons on the m52 rods... Cuz they aren't bent. Should be be the same as m54 lower end without having to worry about the extra 4 mm of m52 piston.
Thoughts ?
Last edited by WhoNew; 04-25-2012 at 11:16 PM. Reason: Automerged Doublepost
Great info! I am a little confused.
In your pics it says left and right pistons are from an m54. I am assuming the one on the left is from an m52 or m50? Please clarify.
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