Hi All, just looking for some advise please on the best route forward. My engine has just dropped a cylinder on my '96 E39 528(M52B28), car has been running boosted on a stock ally nikasil bottom end for over 20,000 miles now, engine has just passed 204,000mls. I was doing a 4th gear pull Sunday night to redline, as soon as I came off the throttle the car dropped a cylinder and then started to chuck out lots of white smoke!! The car was making just over 10psi at low rpm's dropping down to 6.2psi at 5500k+.
I've done a cold compression test, previous warm results only a couple of months back saw all cylinders over 210psi. Now all cylinders were just over 170psi except cylinder 2 which was 10psi and cylinder 5 which was 110psi. If I add bit of oil the results increase, 60psi on cyl2 instead of 10 and over 200psi on the other cylinders, so that was making me think piston rings but possibly head gasket as well due to all the smoke!
I'm pulling the head tonight with a couple of friends to inspect the damage but I wanted to think about my options moving forward...
1. Do I possibly repair this engine bearing in mind its a nikasil ally block and take the chance to fit a mls HG etc to lower compression.
2. Do I swap out this engine for something else?
Engine swap thoughts, I have a friend with an M50 bottom end, so one option was possibly M50 bottom end with the M52 head, but the M50 bottom end may need some work. I also just bought a M50 inlet mani to use as mine was still using the stock M52 inlet manifold.
Other option would just be drop in another m52b28 and look at doing mls HG etc and see how much boost that would take.
The other thought I had and I hope you can help me here, was what about an M54B30, are they any good for boost on the stock bottom end? I know they're ally as well but with steel liners and I've read mixed info online about people running stock bottom end with over 400whp etc. Are they strong, do you need an mls HG and head studs to run over say 10psi and any other things to be aware of? Also is the M54B30 inlet manifold ok or does this need to be changed for something else? I run Megasquirt MS2 so if I went the M54B30 route I'd pick up a stock ecu to control dual vanos and then I'd have to fit a non fly by wire throttle body so those are a few things I'd need to consider.
My car before it died had previously been rolling roaded at only 262fwhp at 5.5psi, since then I'd managed to get it to hold 6.2psi at over 5500k and I'd also increased the ignition advance by 8-10degrees in boost, running about 22* at 3600rpm at 10psi. I was most gutted as it was booked for a another rolling road power run tomorrow to see what difference this had made!! This year I was planning on changing the clutch/turbo/exhaust and aiming for 350hp or more.
So yeah, what are your thoughts on engines, scrap mine, repair it, get another M52B28, M50B28 hybrid or M54B30?
Thanks in advance
Rob
At the power level you are at I think I would just snag another stock M52b28 or put M52 internals in an M50 block and run it. If its anything more than a headgasket it will not be cost effective to repair it.
And get a bigger turbo in there already so you can move some air and not have so much heat and back pressure in the poor thing!
Guys am I missing something?
A b28 blown at or around 6 psi, 260whp?
What turbo and octane? Who's tuning ?
Scratching head on this one
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The part your missing is the teeny wheeny gt25 turbo that is tapering boost from 10 psi down to 6 psi at redline. The exhaust backpressure and temp has to be through the roof.
Start with clearly defining the goal.
Mixing a bunch of parts that are either under or over spec will cause all kinds of headaches.
If you want 350rwhp, any of the stock engines you've mentioned will handle that with a properly sized turbo and charge cooling system. If you want to make that with tiny turbo, none of the engines you've listed will handle it for very long....
Personally, I would keep your current engine, and replace the parts that are damaged. (Head gasket, and upgrade the pistons) Putting a properly sized turbo on the engine will be a big step....backpressure is BAD.
Thanks Guys, yeah the turbo probably was too small but the whole build was a cheap DIY can I do it, so I knew it was never going to last forever, was a learning experience though.
Temps wise, coolant running temps were about 91C normal and 93-95C driving hard/track day with the oil cooler. Intake temps were about 20C driving hard. Exhaust temps were about 300-500C iirc depending on load as I have an EGT gauge in the car.
I took the head off last night and the headgasket has gone and the no2 piston is misshaped and there were two small holes/dents in the cylinder wall. Looks like the piston rings are broken too on no2. I'll get a picture of the piston/cylinder damage up to see what you guys think. I had been pushing the ignition advance lately fully aware that it was risky, but I wanted to see how far I could push it, so maybe I found that limit!!
So it looks like re-using my block isn't an option and to re-use my internals on the m50 block I'd need new rings etc and at least one new piston. The head looks ok but there were a few scratch marks on two of the intake cam lobes. The valves on no2 also looked ok but just oily and gunky whereas all the rest were pretty smooth and clean.
Before the engine went I was looking at changing the turbo, downpipe and exhaust. I think my stock Sachs clutch was reaching it's limit too as it was starting to slip at 4k every now and again.
Oh and fuel was 99 octane.
Last edited by MrMuddle; 01-11-2018 at 07:18 AM.
A couple of pics of cylinder no2.
[IMG]Piston 123 by Rob Devine, on Flickr[/IMG]
[IMG]Piston2 by Rob Devine, on Flickr[/IMG]
looks like the rings expanded and caused excessive friction and damage
Capital Driving Club Car # 102
How to turbo your car:
Step one. Install ecu and learn to tune and or have it tuned.
Step two. Install injectors and retune.
Step three. Install turbo parts and bits. get it running with out leaks. DO NOT DRIVE IT. Idling should be ok
Step four. Retune car
Step five enjoy
Are you able to tell me what would have been likely to cause that, would it just have been heat related and would that have built up over time?
Last edited by MrMuddle; 01-11-2018 at 11:17 AM.
Im assuming this is a stock block and you did not adjust the ring gap on the pistons? if so the cause is due to the amount of heat the cylinder gains from a long 4th gear pull. the ring expands, eventually the ends touch and continues to expand, at that point it is forced into the cylinder wall and binding.
Capital Driving Club Car # 102
How to turbo your car:
Step one. Install ecu and learn to tune and or have it tuned.
Step two. Install injectors and retune.
Step three. Install turbo parts and bits. get it running with out leaks. DO NOT DRIVE IT. Idling should be ok
Step four. Retune car
Step five enjoy
I think Somebody already told you the answer to this question... But I'll try :-)
The turbo is too small and not moving enough air
With the increased inlet temperatures at the manifold + the advanced timing + possible incorrect AFR = Recipe for disaster/ detonation
More than likely stock ring gap closed and the ring either exploded or bulged to the point where the walls were damaged. I think it exploded as the indents are rather deep
I'm sure someone here has a better idea though. What is the stock ring gap for the b28 anyway? And do you know what your AFR was when you were bouncing it off the limiter?
And since where already talking about. And call me crazy for asking but I thought I had read somewhere that it's possible to adjust the ring gap form the top of the motor?
Last edited by 328iFun; 01-11-2018 at 02:15 PM.
Thanks very much for the reply and info, yeah the block is completely stock and I've never opened it up. Its an ally block too if that would make any difference.
Thanks and lol, I wasn't limiter bashing in 4th!! I only took it up to 5000rpm when it happened and the pulls before that were only up to 5400rpm, so no limiter in sight! I was logging at the same time, so can advice temps etc. CLT was 92.3C, MAT was 24.8C, boost was 7psi, spark was 23*, AFR was 12.0.
In regards to the comments about stock bottom ends being able to take 350hp, is that an unopened bottom end or would that be with an mls hg and head studs? As my block is damaged I'm now trying to decide on whether to do the M50B28 hybrid with a new piston and then bearings, rings, etc etc, or whether I just drop in another M52B28 or go for the M54B30. It would be nice to push for more power in the coming year with a bigger turbo and upgraded clutch etc, so it does seem like a good opportunity to build an engine to take the power.
Also do the M52B28 internals like crank, rods, pistons etc fit right into the M50B25 block? Is there anything else I'd need to be aware of/change is doing this combo, other than the replacement bits I'd need to refresh everything like bearings, rings, gaskets etc? My head looks ok, so could get that skimmed if need be and then re-use that with my new M50 inlet mani.
Also decomp plates with two stock hg's, are they any good or to be avoided and just stick with something like a cometic mls hg?
Thanks again everyone.
Last edited by MrMuddle; 01-12-2018 at 04:21 AM.
M50 is iron block, some m52 as well. So, as i know iron blocks is turbo blocks and can keep big torque and temperature. Do not go with m54 due to it has special sleeves with alusil or nikasil which will be damaged very fast with forcing induction. So, do not forget that all big turbo aplications in this world done with iron blocks.
e39 540i 6speed Supercharged,
E36 v8 m62 with m60 headers, Turbp HX-40 0.6-0.5bar or 9psi, custom exhaust & Turbo manifold, injectors 440cc, ECU Invent EMS-2, Mishimoto Intercooler and oilcooler, etc…
Mr. Muddle, If you mean the comlete engine, there are a lot of wiring differences between the m50, m52, and m54. May not be as bad if you’re already stand alone? I don’t remember from your thread if you went stand alone.
Another popular hybrid is the m54 rotating assembly in the m5x block.
Last edited by s13flyboy; 01-12-2018 at 01:33 PM.
Then change just for m52 with iron block. If i am not mistaken USA m52 is iron block when EU m52 is aluminium. M54 all aluminium. M50 is iron. M50 with dme413 is best way due to a lot of standalone plug and play harness available on market.
Currently my local tuner is working with ukranian ecu name is Invent ems2. He had success results on Nissan SUV v8 engine. Soon he will try run v8 m62b44 engine. If he success then i will go with invent which cheap one. If there will be any problems i then go with MS3PRO.
Last edited by dovlet; 01-12-2018 at 01:08 PM.
e39 540i 6speed Supercharged,
E36 v8 m62 with m60 headers, Turbp HX-40 0.6-0.5bar or 9psi, custom exhaust & Turbo manifold, injectors 440cc, ECU Invent EMS-2, Mishimoto Intercooler and oilcooler, etc…
Thanks both, I'm in the UK so the M52's are ally blocks here. Wiring isn't an issue as I'm running standalone MS2 and I don't mind wiring so much.
Anyone able to comment on whether the decomp plates are any good or to be avoided?
Cheers
Many people run decent boost on alusil blocks with success.
I believe the trick is getting the ring gaps correct.
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I know I haven’t heard of any thing specifically associated with the liners on the m54, I know they have more harmonic issues, supposedly due to the alloy block.
PEI330Ci is making some really good power with his from what I’ve read in his thread, and he’d know if there were issues. His threads on the m54 are full of info, and really good pics!
Thanks both, so sounds like I need to look into some gaps some more then if sticking with an ally block. I'll take a look at PEI330Ci's build as well.
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