On the Intake side of the engine machine area Just above the Pan/Sump rail, behind the engine mount Bracket, the bottom number is engine Number, top number starts with engine type ie 20 or 25 or 27 for b20 b25 or b27
Yes, the BMW M20 engine uses a timing belt. It should be replaced (along with the tensioner) every 70000 kM.
To my knowledge the only BMW engine to use a belt is the M20 "baby" six cylinder.
M20 is a tricky engine to see significant changes in performance Naturally asspirated the best bang for the buck would be a performance chip from a reputable tuner Jim confronti chips as well as dinan chips are great a MAF swap will also get you some hp
In the M20 engine it's located on the thermostat houseing, on the M50 it's on the the front of the head intake side.
The earlier single cam M20 engine has 12 valves. All post >91 525's have 24 valve twin cam power units.
I've read that the 1986 325 uses 87 - 91 unleaded gas, its M20 engine i believe. at least that's what i use.
Yes ofcourse the is engine will fit!!! The normal e30 325 engine was based on the m20 engines and the "i.s." was just an upgrade on the 325 engine, using more Alpina based parts. the belhousing to fit the gearbox might need to be changed, however the engine itself will sit nice and snug under the hood. Hope you enjoy your conversion....
M20 - 6.20bags
Why on earth would you want to do that? There is absolutely No benefit what so ever, all you do is risk smashing the sump off even more than normal!
the nearest motorway is the m20 but can also be accessed via the a20 and the exit number is 20... :)
check or replace coolant thermostat or bleed the coolant system
All BMWs have timing chains, there was 1 exception the M20 sohc I6 produced from 1977-1993.