I
Hey Bud, Thanks
pic of engine i took last night
Im a few years late, but I've recently started checking out forum's to help others. I've owned about 37' e30 bmws and amongst those many 325is . This picture of this engine, that is definitely a 535 airflow, part number should start with 028 and end with 086 Without even checking the part number i can tell you its 535 because of the shape on it and also the extra holes and bracket on the side. A Normal m20 airflow isnt like this, i can show you a picture.
And remember also the year models of shadowlines and when i.S started production line, thats the best idea by doing a vin check to see the year build. Cause there were 3 types of vins that came out for i.s
OEJ
OAF
AF
Also another way to tell a i.S check the front suspension the struts must have the bolts under them because they use the e30 m3 suspension setup, but if not doesn't mean it's not an i.s because some people Change the suspension many upgrade to e36 m3 and also because suspension parts for 325is is difficult to source and really expensive. Its better to go with aftermarket adjustable in a case like that.
But best bet again check your vin and the year build number. Also if the vin is OAF or OEJ and it's a 90 or 91 model its Definetly an i.s, all i.s have 5hole suspension. Only shadowline was 4hole . Vin check up is always best bet with bmw and year model most important remember aswell as checking the engine number also on the tag and block to see what engine it is, these day many replica i.s are being made so you need to know your story.