Differences in euro m20?

[ColdAccord]

Bout to put my stroker together, just curious if there were any advantages to the euro m20b25. If it's the same thing, I'm just gonna toss the euro 325i motor into my e, and put the stroker in the touring. THanks

[BavarianBimmer]

Higher CR I think ( our M20's have 9.7 )
Except German models: no catalyc converter

maybe more .....

[ColdAccord]

is that because of different pistons, or is the combustion chamber different? Also, is the intake manifold and throttle body different?

I'm doing a stroker motor, so I'm only using the top end of an m20b25.

The motor is going into a euro 325, so I'm pulling the euro m20b25 to put the stroker in. Does the Euro motor hold a lot of value? it's got 160,000 kms, about 90k miles I believe. Fresh timing belt, etc.

[BavarianBimmer]

the difference is the higher dome of the pistons
I've done some research and I found this


These are the German specs :
(01/1987 catalyc converter equipped )

All M20b25 from 09/1985 have 9.7 CR



All M20b25 from 12/1986 have 8.8 CR



for my country I've found only the 9.7 model
only cars sold after 01/1991 in Belgium need an catalyc converter



With thanks to e30.de ;)




Value of your Euro motor ? I don't know your US norms but I've sold 2.5s around the 800euro's without starter, alt., etc ...

[gstuning]

85 and 86 euro versions without cat must have had 9.4 as it´s also listed as a compression ratio for B25´s

early euro motors make max torque at 4000rpm as opposed to later at 4800rpm or so, or whas it the other way around

[BavarianBimmer]

85 and 86 euro versions without cat must have had 9.4 as it´s also listed as a compression ratio for B25´s

early euro motors make max torque at 4000rpm as opposed to later at 4800rpm or so, or whas it the other way around

strange :

Found in my 1987 manual this for the 2.5i:

9.7 CR
226Nm @ 4000rpm

8.8 CR
222Nm @ 4300rpm

Maybe it depends from country to country?


I've also found for the 2.0i 3 different CR ratings

-9.8 early model w/o cat
-9.4 early model around 87 w/o cat
-8.8 late model cat

[ColdAccord]

hmm. I'm wondering if I should put it in my eta and sell it, or sell it seperately and sell the eta with a shell, or even pick up another b27 to put in the car