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M50/S50/S52 E30 Conversion

Discussion in 'E30 (1984-1993)' started by MGarrison, Jan 14, 2009.

    z31maniac guest

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    No I haven't, but 10-15hp more than an "I" motor doesn't seem worth the effort.

    And a good headgasket, studs, intercooler and tune make 12-15psi a reality which brings you into the 280-300 who range.
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    mooseheadm5

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    You would be surprised. Peak power numbers do not show it all. The 2.7i makes quite a bit of torque, can be done for very little money, and can be done quickly (and reliably.) Turbo motors are a different animal and require much more work and money than a 2.7i. One can spend 5k or more building a good turbo motor, not to mention the labor involved. You can make as much power as you want, really, but that is not what this is all about, is it? Hell, he could go 1100bhp with a giant turbo and an S38B38 if he had the money, or a relatively tame 700bhp with a tubo big 6. I have driven 2 budget 2.7i cars and can tell you that it is definitely worth the effort, especially if it is work and not wallet that make the motor go. Besides, it is all relative. 15HP more than an i is still over 60hp more than his e.
    Besides, tell me that you know someone that can swap in an M50 or build a 200+ HP motor for the time and money that clapping on a used head and wiring harness can be done, and I'll send them $500 of my cash right now along with my car and expect it back in 12 hours finished.
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    az3579

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    I guess my idea of the diff ratios wasn't correct. I learned something today. :)


    If you seriously have one assembled and ready to go (or most of the way there), let me know what else is needed and I'll pay you to get whatever's missing as well. I'm the funding behind the operation, you're the brains. :)

    It seems that 2.7i swap is the way to go. It's going to have comparable power to an M50, a similar redline, but all at a lower cost. I've seen the light and this is the way I want to go!

    A rebuild isn't necessary for this, is it?



    As far as making an offer; well I don't know what these things go for, so whatever your price, let me know and I'll see if it's worth it. Estimated price, do you think it'd be less than $1.5k for just parts? Or if you have an idea, total for parts AND your labor if you're willing to do it? I'm thinking we're working with less compatibility issues and less parts that need replacing/fabrication than an M50, so perhaps the parts will be less.


    If we can find a way to make this work, 2.7i it is.
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    mooseheadm5

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    I will tell you that it will not make power like an M50, but for the money, you can't touch the M50 conversion. Probably less then $1500 for parts unless you buy a schrick cam. I would prefer if you bought the head and prepped it yourself. You will learn more that way (and save money.) Start looking up parts prices (head gasket set, head bolts or studs, valves, t belt and tensioner if you need it, JC chip or similar if you want it) and I'll make you a good deal on the head with bent valves, intake, harness, ECU, balancer.
    A top end rebuild is a good idea (at least lap valves and put in new valve guide seals.) The machine work cost me $110 for milling and valve grinding. A bottom end rebuild will only be necessary if the motor has significant blowby or knocks. If that is the case, you should not consider this to be as quick or cheap as it would be if your bottom end were intact. For the record, my 2.7i went almost 300k before I pulled it apart (over 60k on the conversion with 2 redline runs a day at least.) The original cross hatching was still visible on the cylinder walls and the car used minimal oil.
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    az3579

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    All easier said than done, my friend. I've got a garage in which there is too much of my brother's sh*t to walk a straight line. In English: no space whatsoever to do anything with it, nevermind store it. I'm not touching his crap because if it was up to me, I'd throw out all his crap and make him buy new stuff for being such a disorganized idiot, but then I will never hear the end of it and will probably to have to rebuy his tools for him. I'd rather pretend we don't have a garage at all.


    I'm going to look into a full parts list online because I'm such an idiot when it comes to these things that if you don't say "(4) this-and-that size nuts and bolts" then I won't order it, and the LAST thing I want to do is forget something that I could have done "while in there" and have to pay to have it all done again, or worse, disassemble my daily driver myself and not have a car to drive for a while, even if I don't screw it up.


    Hopefully there is a FULL parts list somewhere online, though I'm too tired to look right now. Tomorrow.

    z31maniac guest

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    My point was that if he has been talking about paying someone to do the 24v swap for him, I would think putting together a motor would be out of the question as well.
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    mooseheadm5

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    Well, it is easier than an M50 by leagues. As I mentioned, it is not that much more than moderate skilled work because it can be done using a Bentley manual, whereas the M50 swap is much more involved. The M50 swap requires pulling motor and trans and changing more than just motor parts, where the stroker i can be done with straight from the yard parts only. Will it make S50 or even M50 power? Not without mods, but it is a good start for a first project (which is why I would rather someone tackle at least part of it on their own.) Many of said mods can be done without spending much (cam, chip, mild porting, gasket matching, head milling.) Building a head can be done on the kitchen table (provided that there is no significant other to complain) and is really hard to screw up. Don't get me wrong, I love power, but on a budget with moderate skill, I would build a stroker i first. Gotta walk before you run. If you want to be able to pay someone to build a car for you, that is just fine. I'll be happy to, but at this stage in life (I am assuming Botond is in his 20s) you have more time than money, so why not capitalize on that and learn a skill?
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    az3579

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    Can it really be done on a kitchen table and not require pulling the motor? I really have no idea what is involved, but if it can be done indoors then I might as well buy whatever I need to buy, replace whatever needs to be replaced, and assemble it before I ever touch my original motor. The main reasons I wanted someone else to do it, in this order:
    * I'm afraid I'll screw something up and there won't be anyone around to help me fix it
    * Repeat the first point
    * Repeat the first and second point
    * Repeat the first, second, and third points three times fast
    * I do not know what is involved, and I'm afraid I'll miss something I could've done that I didn't know about
    * I'd rather have it done right. I know the importance of quality over quantity, and I just don't feel that I'd do a quality job. But, if it can be done with a Bentley manual, then that eases things a very little bit.


    Where can I find a full parts list required for this project? I might as well start ordering things now; my E30 fund is more than halfway there for the components.
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    mooseheadm5

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    I'll come up with a list, but it is pretty short. You can't, obviously, install the head in your kitchen, but with minimal guidance you can disassemble it. Basically there are only a few things you can screw up pulling the head apart or putting it together. Never set it on the valves, never force anything, use the corect tools (don't grab the cam bearings with channel locks or something like that) and follow the procedures. You will have a head built in your spare time with little space while you save up for gaket set, bolts, maybe a cam, etc. If you change your mind in mid project while working on the head, you will be able to sell the head easily for what you paid.
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    az3579

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    Could you please include what I'd need to do for a rebuild?
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    MGarrison

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    Much of it's laid out in the Bentley manual too - read the engine chapter, and you'll start to see what you'd have to do, and much of what you'd need.

    z31maniac guest

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    Clearances inside rotating bits scare me!

    I know when I was working at MerCruiser as a Tech Writer I took a few different classes on taking apart and rebuilding drives so I could write some service manuals. You have really got to have some experience and a good feel for what your are doing, I had a hard time getting the clearances just so.

    And as far as the cost, it won't be as cheap as you are indicating. There isn't a chip anywhere that's optimized for a 2.7i, cam $400, headwork $500+ (someone who has no idea what they are doing shouldn't be taking a grinder/Dremel anywhere near the ports and just start hogging them out), I think you'll easily end up at $2k.

    But you'll have a rebuilt motor as opposed to a used one. So there is that benefit as well.
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    mooseheadm5

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    Having built 2 of them, 2k is a bit high. Also, having built motors since I was 17 and having worked as a professional mechanic for about a decade, I can say that there is actually not that much to worry about if you follow the book. Mild porting (mostly gasket matching) can be done very easily with little experience. Of course, it is completely not necessary. Throw a cam into a completely stock head with a chip and you will have peak HP above an M50. Skip the cam for budget sake but get the chip, and you still have power in the M50 range. Sure, without VANOS you will lack a little grunt, but the truth is, the swap can be done for 50% or less of the M50 swap. There are chips for a 2.7i, you just have to look around. Jim C will probably make one up for you as well.

    z31maniac guest

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    Good to know!

    I hope you realize I'm not trying to argue/start a pissing contest, just want us all to discuss all facets of the possible routes for him to take.

    On a personal note, I just purchased my THR adapter and E28 M5 motor mounts today. Got them used from another local-ish BMW guy, only paid $200!
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    mooseheadm5

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    Of course not. I am just trying to give the best possible options with as much background knowledge as possible. Some have the tools/skills/resources to make an M50 happen, while some should do a 2.7i and be done with it or use it as a stepping stone to learn about tearing into a motor.
    I think you fall into the M50 crowd.
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    az3579

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    Currently I have about $800 saved up for this project and that number will grow over the coming weeks. I'm hoping I'm over halfway there?

    Of course what worries me is that you say that 2k is too much, but I think it will easily reach that number because I have to take my stuff to a shop to have it done; I can't dremel anything. Hell, I don't even know what a dremel is, that's how stupid I am when it comes to cars. Computers? I'll build you one in less than 10 minutes and configure it in less than an hour. A car? Well, that 6-hour brake job explains it all. :rolleyes:

    Even if it is just a rebuilt engine with a different head and cam, it's still essentially just like a brand new engine, isn't it? I get to go through the 'joys' of break-in and all that good stuff, on a 21-year-old car? How cool is that???



    Which cams are we looking at?



    It seems like a mostly straightforward operation, so I have come up with a list. Please let me know if I'm missing anything...

    * 2.5l M20 head
    * Rebuild with all that port polishing and gasket matching BS
    -- What is gasket matching? Are the gaskets different than they should be after the swap?
    -- Is port polishing required? What does this achieve?
    -- What else involved with a rebuild? Or if I mention rebuild to a shop, they'll know what to do with it?
    * Replace cam (which one do I need, from which engine?)
    * Replace all belts and tensioners... (water pump already done recently)

    If I do this project, I will do it the most effective way. If there are options, such as cams, then please let me know about them, because I'd like to fit in whatever I can afford so I don't have to do it later. I'm already factoring in a cam because if it makes or breaks the "compared to an M50" standard, then I'd rather break the standard than fall behind. This seems to be a bang-for-your-buck upgrade, and I think after the most logical "extras" that can be added to the mix, I think it would still be a lot cheaper to do than with a full M50 swap + labor.
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    mooseheadm5

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    $800 is more than halfway if you don't do a cam or rebuild
    Porting is not required. Polishing is not a good idea. Gasket matching simply makes sure that the intake flows smoothly into the head, no gaskets in the way, not lip where the manifold meets the head. You cut the gasket to match the port, the check that against the manifold. Whatever metal doesn't match up, you remove and blend (remove as little as possible.
    Porting is designed to flow more air. Done correctly it makes more power. Done carelessly it can make less power or make the car really top-end biased.
    Bottom end rebuild means main and rod bearings, rings or rings and pistons, gaskets. It may or may not be necessary with your motor, or you may want to build a spare motor on an engine stand yourself (they are practically free and it is very easy and can be done with rented and cheap tools and a Bentley) and have someone swap it in. Top end rebuild means seals, grind valves and seats, sometimes install cam and rockers.
    A cam replacement is not necessary. A Schrick or similar performance cam will make more power, but will require brand new rocker arms, and depending on how high perf you want, new springs. A stock cam will suffice for a budget build and is fine with the rockers, because they wear together. It "can" be replaced later, but it is a PITA to do without pulling the head.
    Timing belt and tensioner. Replace drive belts as necessary.
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    mooseheadm5

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    az3579

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    Wow, that is pretty much the ultimate list of what I should get. Thanks for the link; I'll probably decide on when to buy the parts when I'm more sure of my financial position in about a week or two. I plan on making myself a "2.7i conversion" packet, literally a little book consisting of stapled pages on how to do this so I always have a "you are here" reference; in essence, a "for dummies" book. :)


    I'll get cracking on the parts research; hopefully I'll find most of what I need. Do you agree in most part with what parts are a requirement?
    http://www.strictlyeta.net/technical/328i_2.html
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    mooseheadm5

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    He specs parts that are not necessary (you don't NEED different pistons and rods and other stuff.) Also, you get every gasket you need for the head in a top end set. I think I have most if not all of the used parts you need.

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