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project rebuild M88 engine, bored ,stroked

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in the LOOOOOONNNGGG process of rebuilding the M88 (m5 engine) thats in my 86 e28 m535i at the moment

after it blew its head gasket last year at hampton downs (orginal 25year old 250,000k gasget i think) back in november i think , i picked up another M88 engine and threw that in , then that head gasget went poff as well after a couple more atempts at hampton's ,pulled the head off that one only to find it had big groves in number 5 and 6 bore's from some previous problems/repairs it had etc

so decided to do a full on rebuild of the orginal engine i had in the car .

took the head in to get it all tidied up , new valve guides , planned , cleaned , set up etc .

got the block in at another place to do all the pistons etc , found there is too much wear in the bores and pistons to use , so decided to do a rebore out to 95mm (orginal is 93.4mm) fir custom high compression lighter pistons etc .

also have changed the crankshaft for a 86mm instead of the 84mm one it has (old one had some damage to to the pully end ) .

and i thought while i am at it might as well fit some schrik camshafts.

also orderd in all new camchains , tensioners , water pump , thicker MLS head gasgets also all new top and bottom end gasgets etc etc .

so hopefully it all goes together ok ,

will drop all the parts down the engine guys in the morning .

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Edited by Brent HARTGE535i

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some pics of the old engine in the car with the head off with groves in the bores(no wonder it smoked a bit)

and the orginal one thats being done up etc

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Edited by Brent HARTGE535i

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so what capacity was it and what will it be (you have stroked and bored right),and what comp ratio,was/will?

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cool, so you at hampton on saturday,so i can serve you your ass :D

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So whats the idea of getting high compression pistons then going and putting a thicker headgasket on it ?

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Fantastic Brent.

Quite the BMW Diehard aren't you?

Looking forward to the results, any idea when you will have it completed & running?

hpefully in the next few weeks , just depends on the engine builder guys time , wont take to long to fit back into the car .

so what capacity was it and what will it be (you have stroked and bored right),and what comp ratio,was/will?

was 3.453 10.5c/r

now 3.65L

11:1 c/r

Where did you source the shricks from?

vacs motorsport

http://www.johnmaherracing.co.uk/enginecalc.htm

original=3453cc

New=3658cc

Nice project

cool, so you at hampton on saturday,so i can serve you your ass :D

yea yea thats if you can keep it on the track

So whats the idea of getting high compression pistons then going and putting a thicker headgasket on it ?

stronger gasget , pistons are custom made to suit the gasket thickness etc .

so end result will still be 11:1.

also the block or head can be skimmed to suit if needed

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Wow, those grooves in the bores are wicked.

looks like gudgeon pin marks. Im guessing it was a missing or incorrectly fitted circlip Brent??

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looks like gudgeon pin marks. Im guessing it was a missing or incorrectly fitted circlip Brent??

yes i gues so, the second engine has had some repairs at some stage in its life , had welding on some of the front covers etc ,

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nice rebuild ... one beast of a motor

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So pretty!

You know the drill, It's "So pretty Boss" :D .

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just a quick update .

pistons , crank and rods are fitted in now .

stripping the head down to take the new cams , had to do a little grinding in the cambox to allow for the extra lift in the cam lobes etc .

fit stronger valve springs etc .

have to reorder one of the chain guide tensioner arms as they sent the wrong one .

also needed a new lower cam chain sproket , bottom ned gasget set etc etc .

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i like

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is there something about the cam chain/tensioner that is a weakish point in these, and or s38 engines,or is it just the s38B38?

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is there something about the cam chain/tensioner that is a weakish point in these, and or s38 engines,or is it just the s38B38?

thye just wear a bit quicker than some other bmw engines .

but not that big of a job to replace but the parts are expensive as there are only genuine bmw ones , you can order from a few different places though but all come from bmw germany.

m88 or s38 all wear about the same , 2 types of tensioner rails are used though

and the s38 engines use duplex chain type

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thye just wear a bit quicker than some other bmw engines .

but not that big of a job to replace but the parts are expensive as there are only genuine bmw ones , you can order from a few different places though but all come from bmw germany.

m88 or s38 all wear about the same , 2 types of tensioner rails are used though

and the s38 engines use duplex chain type

thanks brent,rebuild is looking good mate.

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just a quick update .

had to order another tensioner bit from the states #%^$*#& more money:(

as i couldn't get the orgianal long tensioner as they dont make them any more (unless i order a special a one off made one from bmw germany for about $1200)

so have to convert the head to take the 2 piece tensioner system.

as they have already supplied the lower section .

have to drill and tap a pivot pin into the front of the head casting as the earlier head i am using doesn't have the hole there etc .

as you can see in the pictures showing the 2 different head castings.

so they will be assembling together the head and block soon ,so not too far away.

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its so shiney, maybe better to stop now and make a coffee table out of it.

i might come over more often then and sit on your couch,to watch top gear re-runs ofcourse

ooohhh the fun,nothing beats drilling etc into a old block with

unknown thickness before we hit the water jacket.

greatfull its not me doing the job with the cordless :lol:

but then,there always liqiud metal :rolleyes:

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