m20 2.7i

[CrJdMc]

Hey guys, i have a question about this motor build. i have an 87 Is, and its great, but it needs more power, i have heard alot about this swap, and i thought maybe i could just get an eta block, and throw my 885 head on it, and bolt up everything else, am i wrong? i heard you have to use a 173 ecu anyway, are the blocks pretty much the same? i am looking at a block with the bottom end in it for cheap, and i was just going to double check to see if it will work, thanks.

[CHIF8008]

technically. yes.

idk about better power and all that. why not just get a chip and better intake/exhaust?

[CrJdMc]

i have both of those, haha i just want to build a fresh motor to boost. ive also heard a 2.7i conversion could drop compression and is a lot more boost friendly, so ill be excited for that. so far what im thinking is,
- i could just bolt on my 885 head to the 2.7 eta block and bottom end, and it will work fine, and the ecu is plug and play?

[CHIF8008]

few sensors, bits and pieces, but yea. if you are going the boost route then heck yea

[Swanny]

Tons and tons of info on here about this swap. Its been done countless times and will be for a long time to come. Poke around on some of the threads, you'll find very comprehensive information.

[CrJdMc]

are the sensors just little bs sensors? or are they ones that will keep it from running? thanks.

[MattAvino]

^haha

[e30trooper]

Just swap the block complete. Since you car is 87 all the sensors are the same. You only swapping the short bare block. You shouldnt have any issues.
Get the block tested and a leakdown if your not going to rebuild it.

You going to loose top end power but make up for lowend tq.

[CrJdMc]

sounds good, and i will get it hot tanked, and tested. and replace the piston rings while im there. like i said ill be boosting it, so the top end power shouldnt be a problem.

[e30trooper]

sounds good, and i will get it hot tanked, and tested. and replace the piston rings while im there. like i said ill be boosting it, so the top end power shouldnt be a problem.

Might as well get the head cleaned and replave valve guides/seals. Also replace the cam shaft seal/o-ring. Stock headgasted and head bolts are only good for 12psi I heard.. Plenty of write ups on here and e30tech

[jlevie]

sounds good, and i will get it hot tanked, and tested. and replace the piston rings while im there. like i said ill be boosting it, so the top end power shouldnt be a problem.

Do no have the block hot tanked. That will destroy the intermediate shaft bearings. Replacing them is a machine shop operation.

[CrJdMc]

Ok thanks. And yes I was planning on putting a built 885 head on it, with apr head studs and a metal head gasket. Thanks

[e21jps]

dont do it your compression will be way too low!!!

there are lots of ways around it, do lots of reading there is a tone of info on the forums.

In short:
1. put the 885 valves into a 731 head, port match and bolt it on.... this works well done it a few times.
2. find some seta or alpina pistons.... hard to find
3. find some 325/2.7 aftermarket stroker pistons.... $$ best option if your serious
4. look at all the crank and conrod lengths available and see what matches up.... i think a 2.8 crank with eta conrods and 325 pistons will be closest.

add a mild cam while your at it things really start to wake up then

edit:... crap just noticed you said you want to boost it.... yea go for it should be sweet!

[darvo]

I've got a cometic headgasket to increase the compression on this setup, a cometic is good for boost...

You got pm