M50/M52 potential?
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winx
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So you have £2k ready to build an M50/M52 for track use.
What would you do?
I have spent the last year looking at my M30 and ignored the 24valvers and now looking at other options... I want a bullet proof engine that will suit track driving mainly but must be reliable for Nurburgring and LeMans trips!
Having seen DanThe's recent engine a b28 sounds like a good starting point but I also hear rumours of being able to use M54 crank rods and pistons for a b30... Thoughts from those who have been there/done that are much appreciated!
What would you do?
I have spent the last year looking at my M30 and ignored the 24valvers and now looking at other options... I want a bullet proof engine that will suit track driving mainly but must be reliable for Nurburgring and LeMans trips!
Having seen DanThe's recent engine a b28 sounds like a good starting point but I also hear rumours of being able to use M54 crank rods and pistons for a b30... Thoughts from those who have been there/done that are much appreciated!
Me again lol.
What's the advantage of using the iron block? Just strength, or is the ally M52 block really that weak?
I'm looking at running about 400-450 boosted HP and keeping torque fairly low through the M52 B28, would the ally blocked M52 be too flimsy for this application.
Sorry to thread hijack.
For track use, i'd have thought that keeping the front end weight down would be a priority?
What's the advantage of using the iron block? Just strength, or is the ally M52 block really that weak?
I'm looking at running about 400-450 boosted HP and keeping torque fairly low through the M52 B28, would the ally blocked M52 be too flimsy for this application.
Sorry to thread hijack.
For track use, i'd have thought that keeping the front end weight down would be a priority?
E30 340i project in progress now 328 turbo
Breaking '97 728i Auto box, tubular manifolds and other morsels.
For sale E34 M50 sump, pick up and dip stick. PM for de
Breaking '97 728i Auto box, tubular manifolds and other morsels.
For sale E34 M50 sump, pick up and dip stick. PM for de
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Jhonno
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It would be impossible to build a low torque turbo lump to achieve such a thing, unless it is going to only make power at 7k odd and rev to 8/9kMarkT wrote:Me again lol.
What's the advantage of using the iron block? Just strength, or is the ally M52 block really that weak?
I'm looking at running about 400-450 boosted HP and keeping torque fairly low through the M52 B28, would the ally blocked M52 be too flimsy for this application.
Sorry to thread hijack.
For track use, i'd have thought that keeping the front end weight down would be a priority?
Not as simple/cheap as instaling an m52, will probably be knocking on the door of s50 money but for less power, for me its the lack of weight and availability that keeps drawing me back to the stroked m52, i thought i read a post on here a while ago about m54b30 cranks in a m52 but cant find it anywhere ?!
Jhonno wrote:It would be impossible to build a low torque turbo lump to achieve such a thing, unless it is going to only make power at 7k odd and rev to 8/9kMarkT wrote:Me again lol.
What's the advantage of using the iron block? Just strength, or is the ally M52 block really that weak?
I'm looking at running about 400-450 boosted HP and keeping torque fairly low through the M52 B28, would the ally blocked M52 be too flimsy for this application.
Sorry to thread hijack.
For track use, i'd have thought that keeping the front end weight down would be a priority?
I don't know mate, I'm fine at re mechanical side of things, but technical stuff along those lines I leave up to my mate Chip. He was waffling on about using the higher compression ratio, and pushing in more boost up the rev range. It'll drive more like a NA car
E30 340i project in progress now 328 turbo
Breaking '97 728i Auto box, tubular manifolds and other morsels.
For sale E34 M50 sump, pick up and dip stick. PM for de
Breaking '97 728i Auto box, tubular manifolds and other morsels.
For sale E34 M50 sump, pick up and dip stick. PM for de
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DanThe
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Fitting a standard M54 is a bad move IMO, ive had a couple apart and they are not designed to be messed with, they are restricted in so many ways and were designed to reduce emissions, improve efficiency and only 'maintain' the performance and drivability of the M52. The only useful part is the crank and rods/pistons which will drop straight into an M50/M52 block
- bulletproofbob
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well for a N/A built what is the expected power from the M50B28 with the 2.5 induction side compared to the M50B30?? and are we all agree'd the M50 block is stronger than the M52? i was thinking of using the full M52 but i hear there is more lift on the NV M50 cams in my 2.5..... i will be starting to pull the motor apart this evning so i can start making room for the re-build....
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MrBenn
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Well I guess being iron it will be stronger, but the US S52 is putting out 240bhp so BM must have thought it was ok, and from my limited knowledge I think they had to bore the block to achieve 3.2L ??? (not 100% sure on that)bulletproofbob wrote: and are we all agree'd the M50 block is stronger than the M52?
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Jhonno
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Your point is? The S52 is iron blocked iirc..MrBenn wrote:Well I guess being iron it will be stronger, but the US S52 is putting out 240bhp so BM must have thought it was ok, and from my limited knowledge I think they had to bore the block to achieve 3.2L ??? (not 100% sure on that)bulletproofbob wrote: and are we all agree'd the M50 block is stronger than the M52?
- bulletproofbob
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so come on then... rough bhp's and lb/ft for the 2.8 and 3.0?!?
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cool, i'll keep on with the M52B28 build anyway... just wondering thoughDanThe wrote:Standard M52B28 with an M50 inlet 205 -210 bhp 205ish lbft
I will let you know about the M52B30 in due course
I am thinking of going M54B30 route but stripping all electronics and using MS. I thought the only problem was converting the FBW throttle for a regular on, are there any more issues ?
Just that there are some comments about it being rather tricky and costly, i really want good power and low weight for rallying and without cats and MS was hoping for an easy 240bhp.
Am i of track here ? - really need to know cos i am scowering ebay for a cheap lump
Just that there are some comments about it being rather tricky and costly, i really want good power and low weight for rallying and without cats and MS was hoping for an easy 240bhp.
Am i of track here ? - really need to know cos i am scowering ebay for a cheap lump
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Jhonno
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.....DanThe wrote:Fitting a standard M54 is a bad move IMO, ive had a couple apart and they are not designed to be messed with, they are restricted in so many ways and were designed to reduce emissions, improve efficiency and only 'maintain' the performance and drivability of the M52. The only useful part is the crank and rods/pistons which will drop straight into an M50/M52 block
DanThe you are clearly a very clued up bloke when it comes to engine mods etc and just wanted to clear something up as i am midway through stripping an M54B30 and came across this site http://babelfish.yahoo.com/translate_ur ... =TranslateDanThe wrote:Fitting a standard M54 is a bad move IMO, ive had a couple apart and they are not designed to be messed with, they are restricted in so many ways and were designed to reduce emissions, improve efficiency and only 'maintain' the performance and drivability of the M52. The only useful part is the crank and rods/pistons which will drop straight into an M50/M52 block
which sugests that M54 pistons arn't that happy in an M50 due to the differences in heat expansion with the M50/M52 blocks as the M54 pistons are designed to be in an Alloy block not Iron. I currently own a E30 325 and a E36 328 and have considered using it as the starting block for the project, but it would be considerably cheaper/easier to buy an E34 M50B25 engine and swap the crank rods/piston rather than find sump and inlet etc for the M52. Any thoughts from yourself or anyone else with slightly more brain power/experience in engine building on whether this is just one person being extremely anal or that there might actually be some truth/relevence behind it would be interesting. . . . hopefully not just for me
i think your making excuses to empty your wallet here, at your desired power goal your not pushing either type of block end off. If you jump up in CC your making it torque'er low down anyway when a nicely matched turbo install will give you the power and torque your looking for. Think about it at 400bhp your nowhere near 100bhp a cylinder in a 6 potter
Personally all i would do it chuck some ARP rod bolts in, use it and make an informed decision at which point a mls head gasket is all required (internal wise) to run bit more boost and timing. If it goes pop M50/52 are cheap enough to replace in grand scheme of blueprinting an engine with this that and the other internals.
Personally all i would do it chuck some ARP rod bolts in, use it and make an informed decision at which point a mls head gasket is all required (internal wise) to run bit more boost and timing. If it goes pop M50/52 are cheap enough to replace in grand scheme of blueprinting an engine with this that and the other internals.
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Daf318is
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To be fair my M52 did keep up with the 3 litre, it just started to pull away a touch at 90 before a van got in the wayBob_S wrote:M52b30 powered...
better than an m52b28 chariot!

Now driving an E46 320D touring
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DanThe
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It certainly feels like there is a lot more grunt there than a 2.8, different diff ratio?Daf318is wrote:To be fair my M52 did keep up with the 3 litre, it just started to pull away a touch at 90 before a van got in the wayBob_S wrote:M52b30 powered...
better than an m52b28 chariot!
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Daf318is
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Yeah the blue car has a 3-64 I have a 3-73 in mine. What box is in it Dan? Is it Bob's old M42 box?DanThe wrote:It certainly feels like there is a lot more grunt there than a 2.8, different diff ratio?Daf318is wrote:To be fair my M52 did keep up with the 3 litre, it just started to pull away a touch at 90 before a van got in the wayBob_S wrote:M52b30 powered...
better than an m52b28 chariot!

Now driving an E46 320D touring
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Daf318is
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Yep! you can hit the limiter in top and the MPH gauge has disappears somewhere beyond the max readingDanThe wrote:Yeah iS scrap, bit of slack in the input shaft! Will be swapped for an E36 box soon![]()
Had yours topped out yet?
I can live with that

Now driving an E46 320D touring
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E30BeemerLad
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you naughty boy 
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Daf318is
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My engine when it was in Bob's car - it couldn't quite make the limiter. Pretty close though!

Now driving an E46 320D touring



