There are a tonne of differences between TUB25 and a B25/B30. Some , I already mentioned previously , others are injectors, fuel rail, and many many other various small pieces. You can determine by looking at those(you'd have to know what you;re looking for first). If one were to have a TUB25 with a swapped B30 intake manifold and all its components, B30 cats, B30 sensors , MAF and Intake .... You can still find out that its a TUB25 simply by looking up the OBD Values . INpa is a very good software to do so. Obviously you;d have to know what to compare them to otherwise you'd be looking at a bunch of numbers not knowing whats going on. Look at Vanos values, lambda , camshaft and general adaptations. You cant hide nothing, a TUB25 wont run the way it should(proper) with B30 injection system and B30 intake mani. Ms43 ECU might not like(not 100% sure) some of the Ms42 specific sensors and if thats the case, INPA will tell you all that
BUT , if you said someone had stripped one down, meaning no intake mani , no exhaust mani , no crank damper, and all you have is a block with the head attached to it all you need to do is look at the in take cam . B30 has a specific B30 intake cam , all others ,320,323,325,328 share same intake cams . ONly look at the intake cam as exhaust cams are shared thought the whole E46 6 cyl engines apart from M3 and ZHP .
And if one were to go as far as swapping the cams too, well then only thing left is to bust open the head and check the piston clearance , or if you want a quick check then take out your most powerful flash light and look down the spark plug hole after you take the plug out and look at the piston top. B30 has a Unique piston top that sets it apart from TUB25/28 and B22/25 .
You CAN tell the difference , you just need to know what to look for and be prepared to look further.
Now, if the owner changed ALL of that just to hide the TUB ,then I would carve a statue in his name out of solid marble and display it at my friends next gallery.
Last edited by Maple; 09-03-2012 at 07:39 PM.
Reason: Spelling mistakes