info wanted.. m20 2.8 build..

[jbh]

I have the chance of a complete 2.8 single vanos engine for much cheapnes.. only thing is i want to keep the m20 under the bonnet. so heres the thing i want to ask. how do i build the 2.8 m20? whats involved? whats the costs? im about to build a 2.7 from an eta block i have so ill have a spare 2.5 m20 block once i remove its head to put the 2.7 together. so my plan is get the 2.7 buil run it and build a 2.8 through time. any info and advice welcome. whats the power on these? will i notice a great deal over the 2.7 ? is it worth it over the 2.7 ?

cheers James

[march109]

Easy simplest recipe is:

M20B25 head
M20B25 block
M20B25 slugs
M20B20 rods
M52B28 single vanos crank
1 x custom crank spacer thingy.

It is all in the wiki as 2.8 conversion.

[jbh]

Easy simplest recipe is:

M20B25 head
M20B25 block
M20B25 slugs
M20B20 rods
M52B28 single vanos crank
1 x custom crank spacer thingy.

It is all in the wiki as 2.8 conversion.

cheers March. im off for a look and a read up.. any one done this ? whats there opinions

[march109]

Seen my signature? but that was alot of cash for 220 bhp, though some people are seeing 200bhp from simple builds, your ETA 2.7 will be lucky to yield 190 ponies and the build will cost nearly the same.

[Barx325i]

piston skirt machinage required, but a very straight forward

I plan to make one when the weather gets worse. Which will be next week judging by todays rain

[jbh]

would i need to run a independant ecu or could i get the motronic fueling chip changed? is there any one that could supplya chip suitable or would i need toget it set up on the rollers ?

[march109]

would i need to run a independant ecu or could i get the motronic fueling chip changed? is there any one that could supplya chip suitable or would i need toget it set up on the rollers ?

Ant does a suitable chip for your motronic.

[jbh]

Seen my signature? but that was alot of cash for 220 bhp, though some people are seeing 200bhp from simple builds, your ETA 2.7 will be lucky to yield 190 ponies and the build will cost nearly the same.

what all you done to yours to get that power? I have everything sitting to build the 2.7 so my thought is get the car finished and on the road with the 2.7 and build the 2.8 while im running the 2.7 as i know by that time ill be hoping to get another tourer so i can then put the 2.8 in the sport and the 2.7 in the tourer

[march109]

Full head rebuild (doesn't affect power but is nice)
Cam
MAF conversion
Custom Management
2.8L stroker
BBTB

Got me a BTB3 about to go on too, should state the 220 it ran was at Fritz Bitz which is wildly accepted to be optomistic though on the same day a M52B28 ran on the same dyno and made less power (205ish iirc) and the torque was broadly the same.

[jbh]

Full head rebuild (doesn't affect power but is nice)
Cam
MAF conversion
Custom Management
2.8L stroker
BBTB
.

what cam have you used? was planning on seeing a local mob about doing a BBTB for the 2.7 so will see what he comes back with.

[march109]

Schrick 288 iirc, forgot it also has a vernier pulley to keep timing in check.

And still to go on is a lightened fly and BTB3.

[stonesie]

Mine is a bit more tame with its 273/273 catcam but still good for 206bhp / 203 Lb:Ft on motronic, much hooligan fun to be had in the rain

[Gunni]

Easy simplest recipe is:

M20B25 head
M20B25 block
M20B25 slugs
M20B20 rods
M52B28 single vanos crank
1 x custom crank spacer thingy.

It is all in the wiki as 2.8 conversion.

cheers March. im off for a look and a read up.. any one done this ? whats there opinions

I did this , 2.8 stock head + T4 turbo @ 1.1bar boost , 400hp and 466lb´s torque.

[daimlerman]

Mine is a bit more tame with its 273/273 catcam but still good for 206bhp / 203 Lb:Ft on motronic, much hooligan fun to be had in the rain

This zoner's build thread is worth reading,the end result justifies the costs involved.

[goosiegander]

James,

as above, motronic chip from ant, bbtb, 285ish cam, its easy to have the spacer made up and the crank nose bolt machined down...

Its working well for me

[jbh]

James,

as above, motronic chip from ant, bbtb, 285ish cam, its easy to have the spacer made up and the crank nose bolt machined down...

Its working well for me

cheers man. how you finding it?

[goosiegander]

It goes well... lol!

Seriously it could do with a live remap but smae if not better economy than the 2.5 -biggest single spend for me was the cam and im sure you have all the other bits you need for this to hand matey,

no reason not too

[jbh]

It goes well... lol!

Seriously it could do with a live remap but smae if not better economy than the 2.5 -biggest single spend for me was the cam and im sure you have all the other bits you need for this to hand matey,

no reason not too

ive got a bottom end that could do with a rebuild so my thoughts are why not.. will hopefully sell the other bits from the 2.8 engine and box that i dont use to outweigh some of the cost.. my plan is to build the 2.7 the now as i would say all it needs is a new sump fresh oil and filter as with the looks of it its not had a hard life. got a head i can put on but will rebuild another head for the 2.8

[goosiegander]

Good plan,

Another advantage of the 2.8 is not having to deck the block meaning no need for a vernier pully to adjust the timing and dont go for standard bore sizes i wish i hadn't with hindsight...

[StevenC3828]

Good plan,

Another advantage of the 2.8 is not having to deck the block meaning no need for a vernier pully to adjust the timing and dont go for standard bore sizes i wish i hadn't with hindsight...

Goosie -When you say you the above, do you mean you would bore out the cylinders (fit larger pistons / rings) just for larger cc or are you talking about acommodating the extra piston movement the piston / rings travel with the B28 crank?

Love your spray booth by the way!

Guys - Please don't shot me down about this question, I'm trying to learn here!

[StevenC3828]

Guys - Please don't shot me down about this question, I'm trying to learn here!

Turbo Brown on e30tech http://www.e30tech.com/forum/showthread ... 88&page=21 states

" I had custom pistons with the pin moved up 4.2mm, the 84mm stroke crank and 135mm rods.

It's worth checking whether the piston skirts do come below the bottom of the bore whatever you're using, and either checking that there's already a chamfer or providing one if there's not. It's literally 20mins work with a half round file. and then some abrasive paper to smooth it off. Just be sure to wrap lots of electrical tape around the end of the file so you can't accidentally gouge the bores! "


Have any of you M20 B28 guys done this? Goosie / Stonesie / nath / march ? Thanks in advance!

[goosiegander]

The only reason i had my block bored was it was a 82/3mm 320 jobbie, 84mm takes it to standard 2.5 bore/piston/rings, low compression slugs and standard block height mean avoiding adjustable timing gear and allow for forced induction at a (in my case much) later date.

If you want a n/a high compression build use early 2.5 pistons and have them machined to clear the crank,

Better to definatly decide what you want before you start, either way the low compression build is good for 200ish bhp/lbft without mapping.

Still hoping mapping/loosening up will see an improvement in mine...

Hth

Chris

[Nath325i]

It's worth checking whether the piston skirts do come below the bottom of the bore whatever you're using, and either checking that there's already a chamfer or providing one if there's not. It's literally 20mins work with a half round file. and then some abrasive paper to smooth it off. Just be sure to wrap lots of electrical tape around the end of the file so you can't accidentally gouge the bores! "
[/i]

Have any of you M20 B28 guys done this? Goosie / Stonesie / nath / march ? Thanks in advance!

I havnt got this far yet just gathered the bits so far and stripped the engine. Im using high compression pistons for my build but i will soon assemble the bottom end. As said the piston skirts need trimming and i need a spacer machined. I will update my thread soon but bloody christmas is holding up prodction. On the other hand don't think my family would of been to impressed if i spent money this month on rebuilding my engine and coninuing with my shell rather than buy presents

[Zaho49]

I did all of this stage but I didnt do the MAF conversion. Does anyone tell me where can i get the MAF conversion for 2.8 building.

[AlpineAde]

Contact Brody at Miller Performance. They have MAF/WAR Management kits and maps for strokers.

See:

http://www.millerperformancecars.com/

[goosiegander]

Dude,

Did this move forward at all?

[boudy]

hi ive got an early eta block with the sport head was wondering seeing as my bottom end is the low compression one, (found out after much research which i should have done before biting the mans arm off!!) if turbo is the way forward. obviously i will need standalone management what is that like to fit and get working im fairly experienced mechanic any ideas suggestions would be appreciated, ive got 2 325 sport engines and an early 2.7 eta and a cam on its way from shcrick im having the crank and flywheel lightened when i work out which one im using, would there be any benefits to putting the eta crank in the 325 block and 325 head? sorry if its loads of silly questions but am not sure what way to go with my car and its killing me just sitting there!! thanks. tom.

[boudy]

hi ive got an early eta block with the sport head was wondering seeing as my bottom end is the low compression one, (found out after much research which i should have done before biting the mans arm off!!) if turbo is the way forward. obviously i will need standalone management what is that like to fit and get working im fairly experienced mechanic any ideas suggestions would be appreciated, ive got 2 325 sport engines and an early 2.7 eta and a cam on its way from shcrick im having the crank and flywheel lightened when i work out which one im using, would there be any benefits to putting the eta crank in the 325 block and 325 head? sorry if its loads of silly questions but am not sure what way to go with my car and its killing me just sitting there!! thanks. tom.