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**nando** · 08-09-2006, 07:44 PM

I would do at least a light rebuild, with new rings and bearings, front and rear crank seals, oil cooler seals, freeze plugs, and having everything cleaned up. it's not very expensive and your motor will last a lot longer.

first off, you should remove your main bearing caps and rods and look at the crank journals. if they are bright and shiney, you are in good shape - all you need to do is clean the crank, and *maybe* do a light polish. then you need to order the standard bearing set for your month/year of block (early blocks used slightly different bearings than later ones). whatever you do, do NOT have the crank ground - it will be junk.

even a polishing, if it's done too much, can ruin your crank - they have a special hardened surface that only the BMW factory can do, and it's not very thick. if you have it ground this hardened surface will be gone and your crank will not last long at all.

off the top of my head, you want your bearing clearances between .0018-.0022. mine ended up being right in the middle, .0020. check them with a plastigauge ($1 at your local auto parts store).

are you going for custom pistons? you can do an 86mm bore, but I'm not sure that the JE pistons everyone else uses would be good for that - the metric mechanic 86mm pistons use a few tricks to make it feasible. most people seem to stick with the 85mm bore. if you are just going to use standard pistons, you can probably just have the block honed and get new rings, and leave the rest alone. if you are reusing your old pistons have them cleaned and polished - and make sure to check the ring landings for wear. I'm not sure what the factory piston clearances are off the top of my head.

have the deck checked for flatness, and decked if needed. mine was flat enough that they just cleaned it up for me. if you have it tanked leave the intermediate shaft in, and also let them know about the intermediate shaft bearings - they can't be replaced and can be ruined if the block is tanked too long.

also check your rod bushings to make sure they are still tight. the ones on my used S50 rods were like new so I just left them alone.

I would put in a new oil pump, but at least open yours up and check for wear. they are a pretty robust design so as long as it's in good shape you aren't likely to have trouble with it in the future.

also replace all your rod bolts, they are stretch bolts and cannot be reused. lubricate the ends with motor oil before you torque them down. they are torque angle bolts; I made an angle gauge out of an old CD-R with a sharpie and a protractor.

if you do the work yourself I bet you can replace the rings/bearings/etc, have everything cleaned, with a honed & decked block for around $500. when you put it back together use a GOOD ring compressor (the first one I had was junk, caused me to break a compression ring, and cost me $75 to have a new ring shipped overnight). be careful and take your time, it's not very hard to put together at all.

**mops** · 08-09-2006, 11:01 PM

Great thanks for the heads up.

I'll be using stock eta pistons and rods, that is if they are in good shape. I know super eta pistons would be better but those model were never imported to New Zealand therefore I cannot get 'junkyard' patrs. I'm thinking of decking the block by maybe 0.5mm to possibly up the compression to 8.2-8.4:1, do you think thats a good idea ?

All though I am prepared to replace everythig that needs replacing, I dont really want to do full rebuild. I'm aiming for streetable 300-350 crank hp with a turbo. I got megasquirt and other thing sorted out. This is my first project of that kind/extent.

Would you recommend a good online place to guy bearing and piston rings ? Mind you I'm in New Zealand so I need a place that can ship overseas. Getting parts locally is far more expensive than getting them locally. I'll be ordering whole lot, like top and bottom gaskets sets, headgasket, bolts, and any bearing/rings if I need.

ireland engineering is doing a metal headgasket for $190. are there any users of that on those forums (I normally reside on e30tech.com)... are they any good ?

Thanks for the input... greatly appreciated.

**nando** · 08-10-2006, 08:48 AM

Originally posted by mops

Great thanks for the heads up.

I'll be using stock eta pistons and rods, that is if they are in good shape. I know super eta pistons would be better but those model were never imported to New Zealand therefore I cannot get 'junkyard' patrs. I'm thinking of decking the block by maybe 0.5mm to possibly up the compression to 8.2-8.4:1, do you think thats a good idea ?

All though I am prepared to replace everythig that needs replacing, I dont really want to do full rebuild. I'm aiming for streetable 300-350 crank hp with a turbo. I got megasquirt and other thing sorted out. This is my first project of that kind/extent.

Would you recommend a good online place to guy bearing and piston rings ? Mind you I'm in New Zealand so I need a place that can ship overseas. Getting parts locally is far more expensive than getting them locally. I'll be ordering whole lot, like top and bottom gaskets sets, headgasket, bolts, and any bearing/rings if I need.

ireland engineering is doing a metal headgasket for $190. are there any users of that on those forums (I normally reside on e30tech.com)... are they any good ?

Thanks for the input... greatly appreciated.

.5mm is fine, but don't go too far - you'll end up with wacky cam timing.

yeah, you should be able to reuse all the main parts, just replace things like bearings, rings, and seals, and have everything else cleaned up. honing and decking would probably cost about $100 around here, probbaly more where you are though.

as far as where to get parts, I'm not really sure - I get most of my stuff from www.bmaparts.com, they're really cheap if you are in the states and shipping is fast, but who knows about NZ. you can always email them and ask for a quote with shipping. if there are any BMW dealers there it might be worth checking into so you don't have to pay for international shipping and duties, but either way you will want to do your research properly and make sure you have the correct parts the first time.

not too many people here have turbo cars, mostly they are on E30tech. I have no idea of the quality of those gaskets, so I can't comment.

I have a buddy in NZ that wants an e30 now, poor guy is having a pretty hard time tracking one down though. at least you guys get the nice weather! :)

**mops** · 08-13-2006, 05:21 PM

Hello :D

Really thanks for the heads up (my email notficzatino is not working for some reason)

Weather in NZ is pretty bad last few days (read alot or wet roundabouts :nice:)

There are few good e30's to choose from right here right now... .they are not cheap tho ;)

clean and hone the block is relativly ok here, depending how much they want for decking i might or might not go for it.

I do realize i'll definitely go with new rings and gasket set, but i'd definitely want to avoid replacing all bearings/rockers/valves/valve springs/etc...

Oh well.. once I open up engine I'll update.
Thanks.

Mops.

**mops** · 12-14-2006, 06:34 PM

i know i havent updated for a while.

I did some work, but not on the engine.

I was able to source out complete eta bottom end.

right now i'm thinking the following....

-i bock (hot tub and hone) (e block is 0.5mm taller if i wanted 0.3 point less compression)
-e 130mm rods
e crank (I calculated that will result in 8.6:1 compression ratio with stock i pistons)
-i pistons (note that i have early no-cat euro 9.7:1 i pistons)
-new bearings main and rod
-new rings
-new top and bottom end gasket sets
-metric blues 12.9 nonstretch headbolts with custom 3mm washers* done up pretty tight
-stock headgsket
-rebuilt head with oem stuff
-custom turbo manifold (nearly done)
-hx35 turbo
-50mm 4 bolt external wastegate
-custom intercooler
-megasquirt 2 with lc-1 wideband to run it all (already in)
-370cc injectors (off nissan rb25dett)
-bosch 500 hp fuel pump
-stock FPR modded to provide 4 bar over input pressure

so yeah... thats the plan.... some of this stuff is already done or in quite advanced stage....

I still have to work out what to do with clutch.....

**h82crash** · 09-03-2008, 08:20 PM

Uh, there still aren't any wear limit figures on this thread. Been searching myself and not having any luck. Found some for a Porsche 912...pretty loose.

**mops** · 09-03-2008, 08:39 PM

yay for the revival of thw thread ! :)

Since I purchased bentley manual, it has all the clearances some procedures described.

I have completed my engine rebuild few months ago and it's running !

**h82crash** · 09-03-2008, 09:26 PM

I have a Chilton's (flame on) I've had for 10 years and it has clearances but I think they for assembly of new parts. The tolerances are very tight. Example: main bearing .0012-.0028. The figures on the Porsche were .0011-.0031 for new bearings and the wear limit was .0067"

**nando** · 09-03-2008, 09:33 PM

nothing wrong with chiltons - they're all basically just references anyway. I only use bentley for the torque tables and sensor specs these days.

I think my bearing clearances were about .0020. stock sized bearings and untouched OEM crank FTW.

BTW mops - I don't think your build ended up stock did it? care to share what you ended up doing? 2 years for a build is a long time to plan and build. :p

**mops** · 09-04-2008, 02:48 AM

Originally posted by nando View Post

BTW mops - I don't think your build ended up stock did it? care to share what you ended up doing? 2 years for a build is a long time to plan and build. :p

Ah... appreciate the memory.
Well.. as far as engine goes my build was pretty much oem parts (some modified).

Detailed thread with lotsa pix on e30tech...

http://www.e30tech.com/forum/showthread.php?t=55733

I know 2 years is heaps bu really i started actual engine work about march. , so 6 months ago... damn it's long time...

Right now i'm doing the actual turbo install... taking long time but i do *eveything* myself, and i'm trying to have some 'life' outside of the garage.

Anyways, thanks heaps guys, check out my thread for all details :)

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