Jump to content
MikeTheSmith

M50B30 Stroker vs M52B28

Recommended Posts

I've seen a few posts on here lately about people getting bits for their stroker builds and i've seen posts in the past about it being better to just swap in an M52B28. I can't seem to find any comparison between the two though. Does anyone know the benefits of one over the other? Power, costs etc?

 

From what I have gathered the M52 could be used with the M50 manifold and would give more low down torque than a stroker.

Does anyone have any build threads for a stroker? price list etc 

 

Stroker seems to cost about £1k, but an M52 can be bought for about £300 then there is the installation costs and loom mods. But it will be more efficient due to the more advanced engine management. I much prefer the idea of the stroker as its more about building and tinkering with an engine though.

 

 

Sorry if this has all been discussed before, but I can't seem to find it if it has.

 

Cheers!

Share this post


Link to post
Share on other sites

M52 aluminium block is weak- they warp, crack, head bolt threads pull through and some have Nikasil issues.

M50B30 will make more power than M52B28 and will do so with greater durability.

Share this post


Link to post
Share on other sites

nah not quite so j4m35, the M52 2.8 is a hero engine. Yes it had an ali block but they are a very strong engine in reality. What they don't like is being overheated - but which engine does?!  They give great power out the box even more with an M50 inlet attached and for the capacity great economy. Its a great engine of being on that fine balance of everything. 

 

If you go down the route of the stroker then its an engine rebuild and a custom remap to get the most out of it, plud the cost of this will be more alot more imo than bolting an engine in. If you have a M50 e34 then i can see the stroker rebuild idea but engine builds are not cheap 

 

 

But imo any of these single vanos engines are great whether they are 2.8 or a 3.0 stroker build or even more, Alpina took them to 3.2  3.3 and 3.4 - these are awsome engines! 

Share this post


Link to post
Share on other sites

So this is from Wikipedia as a comparison for info:

 

 

Engine Displacement Power Torque Redline Bore Stroke Compression ratio Year M52B28 2,793 cc (170 cu in) 142 kW (190 hp) @ 5300 280 N·m (210 lb·ft) @ 3950 6500 84 mm (3.3 in) 84 mm (3.3 in) 10.2:1 1995 M50B25TU 2,494 cc (152 cu in) 141 kW (189 hp) @ 5900 245 N·m (181 lb·ft) @ 4200 6500 84 mm (3.3 in) 75 mm (3.0 in) 10.5:1 1993

 

So max power comes on a little lower in the rev range on the M520 and has greater Torque also lower.The M50 manifold mod for the M52 sounds like it looses some of the low down torque but makes more power higher in the rev range.

Does anyone have any costs of these options?

 

At the moment i'm not in a position to do anything with this info, just trying to work out which pipe dream to have :) 

I guess the idea would be to put it into my ix. Is there any issues with this being an auto with either option?

 

Thanks for the input so far!

Share this post


Link to post
Share on other sites

Bumbaclut I'm not just contradicting you for the sake of it but for what it's worth M52s are famous for stripping head bolt threads for fun whether they've been overheated or not and there is the Nikasil thing, sure there are plenty of Alusil ones knocking about.

Yes a used M52 is cheaper than building an M50 stroked but since when is a used engine vs a rebuilt one a fair comparison?

M50 is undeniably more robust and because the architecture and cylinder head design is very similar there is no power advantage to the M52, the only benefit of the M52 really is lower weight.

Share this post


Link to post
Share on other sites

My M50b25 Wagon is hopefully getting its stroker build over winter, price quoted by a local BMW specialist with me providing the crank, rods & pistons is £1600.00

Includes full stripdown, everything cleaned, new rings, bearing shells etc. as well as a head rebuild and hone.

 

C.

Edited by cableguy

Share this post


Link to post
Share on other sites

An M50TU is an M52 the only differences are the engine capacity's the management is much better on the M52, the block is also is ali, the inlet manifold is different. In the USA the M52 retained the iron block. There is no such thing as an alusil M52. Alusil blocks and V8's exists but on the M52 BMW fitted steel liners into the ali blocks to cure the nikasil problems. If i had the choice? I'd take a nice running nikasil engine in the long term and keep the cooling system good.

 

An M50/M52 with good servicing is an engine that makes the power into old age and is very very robust. If the MAF/O2 and other sensors are good and keep the oil changes rolling

 

The M50 isn't tougher than an M52 as the mechanics of the engine are the same, its just the M52 is harder to repair if its overheated. Its also alot lighter than an M50 with that ali block!  

Share this post


Link to post
Share on other sites

Mike, for the iX one of the main issues you will have is that the iX already sits high so putting in an Ali blocked engine wiht the consequent loss of weight means it will sit even higher. To resolve that would mean fiddling around with the suspension and given the only supplier of front iX suspension is BMW, I think you don't have many options here except to swop to sports shocks and springs.

The engine bay electrics are further complicated by the fact that the iX uses an unique engine loom, presumably because of the different engine position. So question for Spice Boy, did the M52 loom fit easily into the M50 engine bay?

My plans for my non vanos iX are to stroke another non vanos unit I have to 3L using the M54 internals and put that in the car using the existing loom and engine management. It's the simplest option.

It's not ideal as the best combination would be a single vanos 3L with an steel lined ali block with M52 engine management system but I am not going to go to the expense of preparing an M52 block for that extra capacity unless I could use the M54 block which is also available. So question for Bumba, what are the issues around using the M54 block instead with M50 or M50 TU head?

Edited by Dongiov

Share this post


Link to post
Share on other sites

The simplest and cheapest option is to fit an M52b28 and run it on the OBD1, which is what I did over 5 years ago now and has been completely trouble free despite covering over 20k a year.

 

At some point in the future when it doesn't do so many miles I would like to put a 'big 6' or V8 in it and standalone management. 

Share this post


Link to post
Share on other sites

I think the IX engine loom difference is the extra transfer box wiring

Alpina went with a 2.8 crank (86mm stroke) and bored out the m50 block to also 86mm for the Allrad 3.0 - not sure if the 89mm odd 3.0 crank was available then?

Share this post


Link to post
Share on other sites

Bored and stroked as per alpina would be the best way I would think else the engine may end up a bit under square. Good for torque but a bit unwilling to rev. Think of all the British pig iron of the 50s and 60s giving us long stroke sloggers ( some tax reasons iirc) where as the Europeans got some fizzy revers like the twin cam and m10

Share this post


Link to post
Share on other sites

indeed there is no parts swapping between M54 and M52/0 stuff mainly because of the double vanos heads - the double vanos brings nothing to the performance party, the exhaust vanos just cleans the emissions up. The single vanos is best for performance, alpina stuck with it into the e46.........plus the heads are clearly a good design and with the right bits and bigg CC bottom ends flow enough for well over 300bhp.   There was also a double vanos M52 called M52TU fitted to early e46's late e39 and e38's and the cranks on these are different to single vanos they have bigger crank webs for some reason and won't fit in an M20 block without machine work. pointless trivia

 

The steel linered engines can run into problems where the ali blocks sink lower than the liners casue headgasket problems so i've heard. I've never had a steel linered M52 only nikasil engines. 

 

For the cost if i was building an big CC M50 i'd be getting a nice light single mass flywheel and having the whole bottom end balcanced. Should be less than £200 all in if you hand the parts over nice and clean. Makes a nice difference even on a nice smooth 6 pot 

 

The 3.2 engines are 86mm bore but i'm not sure of the stroke, these make nice power but they don't rev like a nice 2.8 M52 does

 

Alpina went with their own custom crank of 94mm and a 86.4mm bore to get 3.3 and loads of torque, the later B3S engine was bored to 87mm with the same 94mm stroke to give 3.35cc but called the 3.4 these badboys give nearly 270lbs of torque and you get 90% of it from 2500rpm. but these like a headgasket as the 87mm bore really is as far as you can go on these engines plus the gasket is unique to this engine and £400+VAT from BMW only. Ask me how i know!!!  3.3's use the stock BMW gasket, there is one of these engines forsale in scotland, would be epic in an e34 touring. 280bhp and the same economy a 525 would deliver

Edited by Bumbaclut

Share this post


Link to post
Share on other sites

I thought the 3.4s where a bit thin on meat so if they score the bore there is nothing left to hone so you have to start again with a fresh block? This is a vague recollection of a conversation with Phil crouch when I collected my m3 after repair at cpc.

Share this post


Link to post
Share on other sites

No bore work needed. In fact, no nasty modifications needed apart from shaving off some of the cam if you want to use the 3.0 inlet cam. You will need to raise the head via a thicker gasket iirc.

The 3.0 parts fit into the m50 easily. Piston size is the same. Also, the piston rods are forged from factory so will handle tidy power.

Share this post


Link to post
Share on other sites

The BMW 3.0 is a stroker as the bore is still 84mm iirc like the 2.8 2.5 engines, just the crank throw gets longer on each one. Going 3.0 is when they start boring out to 86mm 

 

Duncan its true there are no oversize pistons listed for the 3.4 engine as its as far as you can go with them. But if your block was scrap then you could always get an M50 iron block and bore it out and off you go again. From when i rebuilt mine the piston rings are also unique to that engine also. Saying this they are a big step up from the 3.3s and really rev more like an M-engine than M50 series as in the end the inlet, exhaust manifold and system, camshafts, head work, ECU, crank, rods, pistons are all Alpina on them. They're a very alpina engine! 

Share this post


Link to post
Share on other sites

Would another option be to get a full m54b30 and run it as is on m50 sump, throttle, inlet, thermostat etc and standard management with a remap? As if you take all the "new" electrical controlled bits off surely it could work? Cheaper than building one and might give more power with an m50 inlet if it'll fit and remap? There 231 as standard maybe 240-250bhp could be achieved this way cheaper?

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

The m54 produces less torque than a 3.0 m50. The m50 inlet manifold does not fit and the average 3.0 m50 produces 240bhp+ maybe more with a harsh map.

Share this post


Link to post
Share on other sites

The m54 produces less torque than a 3.0 m50. The m50 inlet manifold does not fit and the average 3.0 m50 produces 240bhp+ maybe more with a harsh map.

 

Hi Craig, these figures are brill, where did you get them from?

 

Looks like I will be doing that iX conversion then.

Share this post


Link to post
Share on other sites

Hiya Geoff,

Those figures are from tried and tested rebuilds that have then been on a rolling road. Even giving for slight inaccuracies between different brands of rollers these seem to be the given output from the upgrade :-)

Share this post


Link to post
Share on other sites

So what is needed to build a 3.0 M50?

M54 crank and Pistons

New bearing shells

New piston rings

New head bolts

Remap

Just wondering where the costs come from really? So is it all of the May as well do while I'm here items? Sounds like it would definitely liven up the ix. Still the m52 would seem to be the "sensible" option. I guess you could keep the iron block from the m50 and the odb1 for simplicity.

Share this post


Link to post
Share on other sites

Engine mounts maybe should be put on the list.

 

Also, iX's by their very nature get used more in salty conditions than other E34's so it's certainly on my list to get any rust in the engine bay or front bulk head sorted at the same time.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×