M20 Stroker Build Questions

[Forrest 35]

I am seriously considering doing this in the summer/next uni holidays if funds and time allows, and thought I would make a thread to ask some noobish questions, and see if anyone can help me with knowledge and helpful links from other forums for info and a way to do this.

I know it isn't the most cost effective modfication, or why not just go m50 etc etc but I have never done any serious modifications to any motor out of any of my cars, I have 6 months ish to save for this so why not start now.

I want to keep the car going while I do this, so I am more than likely going to find a spare m20b25 and go from there, I want a late 2.5 motor with motronic 1.3 obviously because they can be remapped/chipped unlike the current 1.1 in my car, so that conversion will be definitely happening, or just find a early motor and I have access to a complete 1.3 loom and ecu.

I have access to: E36 M20B28 crank shaft, E30 M20B20 Rods and obviously a 1.3 loom and ecu if I need it (to end up with a m20b28, obviously I would need new gaskets and so on also. Is there anything else I need? Is there any difference internally with the early and late motors, and is it easier starting with one or the other??

And there is thoughts of maybe putting a set of those recently posted m20 ITB's on afterwards, but that is just me dreaming

Excuse the noobness, I am new to m20's so any advice, links or input is totally welcome, and yes I have searched

Cheers, Nathan

Edited July 27, 2009 by Forrest

[*Glenn* 855]

I had a really good link for this mod... I might have it at home on the laptop.

Dan (driftit) has a copy.... PM Dan for the link and I'll have a look at home as well

[Forrest 35]

^ Cheers Glenn

[skidz 197]

Can do a facelift M20B20 complete motor with loom computer and all accesories, plus 2.7 high compression shortblock, plus Alpina C3 2.7 chip, plus headers (that need some work) was thinking $1,000 as a package - some assembly required!

[Forrest 35]

^ Don't tempt me I will have a chat about that when I come round to get those interior bits, cheers Stephen.

[Nobimmer 694]

I think that Andrew tried the ITB route, but said somewhere that it would end up costing over 4k to do properly?

[Forrest 35]

^ Itb's are a bit of a dream really, would rather do a tidy 2.8 and be done with it. Car goes fine in current trim, but has a slight worn cam (current motor has done 304k), so needs something to freshen it up in the next 10,000k or so.

And Dan the previous owner was going to do a 2.8 anyway, so I thought I would let the dream live on

Edited July 28, 2009 by Forrest

[Nobimmer 694]

If you get that link, put it up. Would be interested to read it also.

[Palazzo 479]

Along this line, if you build a PFL motor (higher compression according to manual), will it run on a FL computer?

[Forrest 35]

^ I need the answer to that, one would hope so. I am pretty sure I know of a few people that have converted to later motronic on a PFL motor with success, would want to be sure first though.

[tire 10]

epic link

[Forrest 35]

^ Pretty much going to name my first born after you now Max

[tire 10]

No worries - e30zone wiki ftw!

[*Glenn* 855]

The link that I had was the same as the one Dan's got. I posted it in here somewhere, but I cant find it. It was a UK one where the guy fitted it into a kit car. PM Dan (Driftit) for it. Its a good link with pictures and covers the whole build.

[Forrest 35]

^ Have Pm'd him, will do a search too.

[antil33t 90]

Lucky bugger... I sadly live in a Flat, so have no money to build fancy strokers!

Oh how it's tempting to move back in with mummy and daddy to build such a thing.

[BM WORLD 1286]

epic link

this is the one

http://www.msportster.co.uk/detail.asp?cat=22&offset=48

Edited July 28, 2009 by Brent HARTGE535i

[*Glenn* 855]

this is the one

http://www.msportster.co.uk/detail.asp?cat=22&offset=48

Yes...thats it..I've saved it again. Must have lost it on the upgrade changeover

[Forrest 35]

Lucky bugger... I sadly live in a Flat, so have no money to build fancy strokers!

Oh how it's tempting to move back in with mummy and daddy to build such a thing.

Yeah moving out next year, so if I am doing this I want to do it right first time round.

this is the one

http://www.msportster.co.uk/detail.asp?cat=22&offset=48

Thanks heaps Brent, really appreciate it.

[antil33t 90]

Yeah moving out next year, so if I am doing this I want to do it right first time round.

Yeah, no point doing sh*t twice.

[Guest FrantiC]

It can be done on the cheap guys.

I went with a ETA high compression (10:2 , You can get older 11:1CR ones too) with the 885 (325i 2.5L) head.

Nets you a ~9.5:1CR and is pretty easy to build as you don't need to swap around pistons etc.

I bought a 2.7 short block from an 88 525e from some asian guys in Auckland, Bought a complete m20b25 and used the head etc on my motor. Then just got a 1.3 loom, and pretty much you bolt everything from an m20b25 (intake, loom, FPR, ecu, exhaust, AFM, throttlebody etc) to the 2.7 short block

Stephen told me the ETA pistons do not work with the 885 head, but I can vouch for a fact they do though they aren't designed for eachother. As the 885 head is designed with the 2.5i pistons which are domed, and the ETA pistons are flat so they don't match, so it's not a perfect match but the power is definitley still there and the low end torque is awesome. For me it was a cheap side project to upgrade from my m20b20. Was definitley worth it, very rev happy powerfull motor.

Cost me around $2000, Only because I bought a full 325i motor off stephen (and it didn't have most of the 1.3 sensors, toothed crank, had a 320i intake mani. and throttlebody so had to source m20b25 parts from others, all I used of him was the 885 head and the 164 ECU he gave me) Also new gaskets all around basically. Could have been done for way cheaper though. Definitley worth the cost IMO.

Oh, and LIVE AT HOME FOR FREE FTW lol

Edited July 28, 2009 by FrantiC

[Forrest 35]

^ Did you get that ECU chipped?

At the moment a 2.8 with the m52 crank seems the more easier option, or just buying Stephens motor off him

Edited July 28, 2009 by Forrest

[Guest FrantiC]

Nope, I ran the standard motronic 1.3 164 ECU with larger injectors (e36 325i, 17.5lb/hr).

Ran awesome as, very rev happy.

At the moment a 2.8 with the m52 crank seems the more easier option, or just buying Stephens motor off him

Up to you bro, Just letting people know the cheaper easy way lol for people like me who wanna go on the cheap, but reliable (I don't mean cheap half ass either). Cos all you need to do is bolt head onto block and go from there. If I had the money I would have pulled the block apart and used the 2.5i pistons to suit the head, but the pistons need to be modifed to be used with eta crank and rods.

Edited July 28, 2009 by FrantiC

[Forrest 35]

^ Cheers though John, being a student I don't have a lot of disposable income, and since the motor needs a little bit of love I'm happy to do it the right way first time round, but obviously don't have an endless budget, bit of thinking to do methinks.

So I guess going from what you said the best thing would be to find a complete 325i facelift motronic 1.3 motor and put the head from that on a 2.7 eta block? Which pistons would I need?

I think from what I have read so far, regardless of whether I do a 2.8 or a 2.7 I need the later motor anyway

Edited July 28, 2009 by Forrest

[Guest FrantiC]

Yup, No matter what you decide, if its an m20 stroker the best head is the 885, having bigger vlaves, ports, good flow etc. So yeah easiest way is to buy a complete m20b25 motor with loom etc so you can get all the bits like FPR, AFM, Loom, TPS, toothed crank wheel and crank angle sensor, intake manifold and exhaust manifolds etc.'

Cos that's basically it, the rest is in the block you choose and what goes inside makes the rest.. Easiest way for a 2.7 stroker is just use the high compression ETA block and pistons. It's what they use in the U.S though theirs are lower compression to start of with , so ours obviously are better power.