My VOLVO MODEL 850 T2
 

I would like to more about it's specificstions.

t2? not sure what you are looking to learn - but there's enough resources on line - some good resources - volvotips.com volvowiringdiagrams.com any dealer web site (for part numbers and diagrams) and I bet if you google "volvo 850 haynes manual PDF" somebody has scanned one and posted.

I see lots of refrences to T5 models, haven't found T2.

Same here. I don't know T2.

Right, the car is a Terminator and will smoke you (sometimes from the dipstick)! The model no on the plate under the hood is. 855 T2 .186223. GG/HEUS. Looking for any significance of the no.

better to use a VIN decoder to find your engine model or look for the engine code. Your VIN should say something like YV1LW56 or YV1LW57. The W means wagon (S means sedan) the 56 and 57 refer to the engine type ie B5234T is the code for the 5 cylinder 2.3 Liter Turbo. Look around for any build plates with a B5xxxxx code and you will know your exact engine.