rebuilding an m20 2.7i help

[kickinindian]

so i plan on doing a basic 2.7i build putting an 885 head and all the 1.3 motro stuff on the eta and put it back in but i want to clean up the block and rebuild the head myself to save cash, plus for the learning experience:D

so im wondering what i will need gasket wise and parts wise to do a basic stock rebuild. and or if i shold add or change anything

m20 head gasket kit (do i use the b25 kit or the b27?) also where can i get a non VR kit?

lower end gasket kit, same as above no VR

water pump

timing belt, tensioner (contitech)

acc. belts

new spark plugs

head bolts/studs (metric blues?)

also can i use all the metal in the head again? (rockers, cam, valves etc.) as long as they are not bent?

i guess im just asking for someone to tell me the basic no extras, but a solid rebuild set up to refresh my m20.:up:

[jlevie]

The head should go to a machine shop to have the guides checked for wear and possibly replaced, the valves ground and at least a minimal surfacing cut done on the head to get it flat. It should also get new valve seals.

If not worn, the rockers, cam, and valves can be reused. If the head has high mileage (over 150k) it will probably need new exhaust valves. To tell if the cam is worn you usually need a Cam Doctor report.

I don't know of any kit other than the VR one. But it is easy enough to order the OE gaskets/seals from your dealer. Use the M20B25 head gasket and get new head bolts, copper plated exhaust manifold nuts, and down tube nuts.

[kickinindian]

Gotcha I plan on having all the machining done and such and get the valve grinding stick thing.
I'm thinking I'll get the VR kit but get a Goetz HG and then just use bmw head bolts

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[SkiFree]

i guess im just asking for someone to tell me the basic no extras, but a solid rebuild set up to refresh my m20.:up:

As jlevie alluded to, no one can tell you except your machinist. To me a solid rebuild means replacement of the items you mentioned (rockers/shaft/cam/valves). What your doing sounds like what you aim to do is an inspection and refresh.


In addition to VR there are Elring UPPER gasket sets available (I've got about 5 on the shelf at the moment). But VR is the only LOWER gasket kit available. I happen to really like the VR paper oil pan gasket compared to some not so great experience with the flimsy oem cork gasket.

If you want to inspect your cam/rockers

http://www.r3vlimited.com/board/showthread.php?t=309495

[kickinindian]

Cool Yea i can deal with the bottom end gaskets I just don't want to redo a headgasket for as long as possible
Should I do new main bearings too or is that gonna have to make me do new ring and alot more

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[SmokeE30]

I wouldn't just do bearings and rings if they are worn and warrant reacement yes but most likely the bottom end will be in fine shape it's the top ends that wear out more. But that again is stuff for a machine shop unless you happen to have the tools to do that stuff

[kickinindian]

Lol no I definitely do not have that stuff I just want to have a good running DD that will last for at least a few years since I love the car

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[Regnar75]

so im wondering what i will need gasket wise and parts wise to do a basic stock rebuild. and or if i shold add or change anything

m20 head gasket kit (do i use the b25 kit or the b27?) also where can i get a non VR kit? I believe both head gaskets are the same as the bore is the same between the m20b25 and b27.

lower end gasket kit, same as above no VR. not 100% but i think its also the same

water pump Yep you can reuse it but highly recommend you change it out

timing belt, tensioner (contitech) sure

acc. belts i ran into one issue here, the harmonic balancer from the 325i which you need has a different diameter track for the alternator belt. you have to use a shorter vbelt otherwise it wont get tight enough. check the 2.7i build thread, i put a long post in there with the belt size i used, should be towards the last page. AC and PS are the same though as the E

new spark plugs i would definitely update/upgrade these, im pretty sure they have slightly different specs (e and I) stick with copper though.

head bolts/studs (metric blues?) unless you plan on FI, i dont see the need as stock bolts will do, but do no reuse obviously, and make sure you have proper socket for the new bolt pattern by BMW

also can i use all the metal in the head again? (rockers, cam, valves etc.) as long as they are not bent? yea, but as other people have said it could be worth replacing some things like valve stem seals which i think come in head gasket rebuild kits. also try and do a valve job, if your noticing some issues or flat spots in the eccentrics then replace those as well. everything else is just more money and good if you have the time/money.

something that can save you a lot of heartache and is good idea to replace are your sensors. (on tstat housing. the CPS, oil level sensor, oil pressure sensor all have different connections from motronic 1.0-1.3 so you can do a splice job or just replace the sensor with one from a later date) the CPS is a no splice option you have to use 325i one just make sure to grab the bracket that it mounts to and oddly enough the eta block should have the holes to mount the bracket.
The o2 sensor is also worth replacing but if you mate up the eta exhaust to the I head i would recommend splicing the sensor end and hook it to a spare motronic 1.3 end that way you dont splice your engine harness and can replace o2 sensors when you need to. the 325i o2 sensor, while having the correct connection for 1.3 will be far to short to reach the eta's o2 sensor location (by transmission)

With basic belts, gaskets, waterpump, and sensors replacement as well as extra care when doing your timing belt timing, it will be a solid refresh and can take care of many of the no start issues you might have after doing this build. please refer to the 2.7i build thread sticky for more details on the actual parts from the 325i you will need as there are a lot more than listed here.

i guess im just asking for someone to tell me the basic no extras, but a solid rebuild set up to refresh my m20.:up:

[NJ2.5rser]

Hey I just posted up an article about the 2.7i build in this topic it'll have all the information about what you need/what's been tested via a couple shops in Europe. Check it out it should answer all your questions.


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