2.5-2.7

[whippy]

eta 327 vs alpina 327?!?!?!

No contest, my pina would kick an eta conversions ass any day!!!

Just look out for a genuine alpina lump (& manifold if you can), one went for only Ԛ£400 on eBay not too long ago.

Stuff 2.7, if you are going to build one yourself, it's easier to go for 2.8 if you have a M20 2.5 engine to start with

[oze30]

And how would you go and do a 2.8?

AFAIK, the way i'm doing the 2.7 is almost the same. just difvferent cam... so i don't see how your's would kick ass over a proper conversion??

[whippy]

I've made a 2.8 out of a m20, now working on a 3.1. Quite easy when you know how. lol

We should go to a santa pod meating and put yours against me pina

[oze30]

I'd rather not thrash the crap out of my car and bust some driveline while i'm at it thankyou. I'm very sympathetic to my car

HOW did you do the 2.8? and how you doing 3.1? very interested as I may decide to change my capacity

[whippy]

I made it up out of parts I had lying around. Trial and error, lol.

I know 100% what the grank and pistons are from, but only 70% sure where the con rods come from. As soon as I know, I'll be puting a full article on here. Watch out for it.

P.S how do I make my image smaller?!?!

[ian325is]

To convert a 2.5 to 2.8 you just use the crank from an E36 328 M52 with 130mm rods from eta or 320. Some simple machine work neccesary to nose of crank. 325 pistons will need 11-14mm machined off the bottom to clear crank. Same story with early 325 pistons and 2.7 crank. Block can be used as is.

For the 2.7, the block will need to be decked 2mm regardless of which pistons you use. It is the length of the piston skirts that are different.

[oze30]

Whats the power diff between 2.7 and 2.8?

Ant can you call or pm me re: 2.7 build.. IUm starting to get lost in translation here re: cam

Cheers,

0782 108 7679

[Simon13]

Genuine alpina lump for Ԛ£400 i'd like to see that!

there was a certain les stannard built 2.7 eta which was on this forum which would hand an alpina 2.7 it's arse

Alpina's need a better cam really to finish them off

3.1 M20? i bet thats going to rev well

[ian325is]

3.1 is not such a good idea. Conrods will be too short in relation to the cranshaft throw resulting in huge piston slap.

[Andyboy]

3.1 is not such a good idea. Conrods will be too short in relation to the cranshaft throw resulting in huge piston slap.

I think it's bullshit anyway! It can be done using a 3.2 Evo M3 crank and rods with some weird Bike pistons.

I did a 2.8 M20 3 odd years ago. The crank doesn't need machining but you need to make a spacer for the nose of the crank fore the M20 crank oil seal to sit on. I used an M52 centre pulley hub and turned it down in a lathe. For some reason it was a pretty tight fit on the M20 crank (a tap fit as opposed to just sliding on) but i got around the possibility of it turning by drilling and dowelling it to the front crank pulley.
The advantage of using a 2.8 crank is that the stroke is longer - using 325i pistons and Eta/320i rods the pistons come perfectly to the top of the bore so unlike the 2.7 stuff you don't need to mill 1.5mm off the top of the block.
The engine I built is in Adams car. Using early 325i 9.75:1 compression pistons and it has a CR of @10.7:1.

[bmwscorpion]

Ive just read all the way through the posts, when the engine is fitted with Zone 2.7 chip which AFM shall I use 320 or 325? .. or is there a difference.

Belive it or not Im building my 2.7 outside in the fog and minus tempratures today, it is nice to be inside..

Thanks

[oze30]

Ive just read all the way through the posts, when the engine is fitted with Zone 2.7 chip which AFM shall I use 320 or 325? .. or is there a difference.

Belive it or not Im building my 2.7 outside in the fog and minus tempratures today, it is nice to be inside..

Thanks

Id say use the biggest you got.. so 2.5