Hi Ron and net. I probably missed some of your thread. What is your ultimate goal for the collection of parts. If you could send me a few pictures off net perhaps I can help identify them. As for the case, type 1 and 3 are similar as are type 2 and 4s. 2/4 cases have the square tower with the oil breather near the pulley end of the engine. As for the crank, the end of the type 2 and 4 is different then the type 1/3. The end of the type 4 is tapered The crank can be measured from the center of the rod journal to the center of a main journal. for example type 2/4 can have 66, 71 or 78mm. The rods are matched to the crank in that 66mm rods wont fit the 71mm crank. Heads are also somewhat distinctive. type 1/3 have exhaust ports on the ends, type 2/4 have the exhaust on the bottom of the head. Then there are single port and dual port heads, some with three bolt and other with 4. The pistons can be measures to determine diameter. With diameter, stroke and head cc you could determine total displacement. Don't assume anything as far as oem, these engines were made in several countries and even aftermarket for others. After 40 years some or all could be aftermarket.
get your book and a good ruler measure make notes and call Steve Bennet at GPASC, and talk to him about the differences. you can go into some of the web pages of the members who are using VW's and look at their engines .Orma L. Robbins N110LR 1984 to present
