How can I tell if my '86 VW engine is a "HT" or "RD"?

I just bought a 1986 Vw GTI and am trying to purchase replacement parts through my local automotive store. However, when I went to place an order, they wanted to know if the engine was a HT or RD engine. I'd never heard of this before, and neither had my father, a former GTI owner. My googling skills have been exhausted, and I hoped that someone who knows more about Volkwagens than I do was looking for questions to answer. Danke sch枚n!How can I tell if my '86 VW engine is a "HT" or "RD"?On the side of he block, usually near where the engine bolts to the Transmission is the engine stamping.



It is stamped on both sides and may be seen from the back side of the engine when under the car.



www,vwvortex.com the Golf 2 forums will probably have pictures of the differences.How can I tell if my '86 VW engine is a "HT" or "RD"?Just look on the engine ID pad, on the front of the engine, it will tell you. I believe the HT had knock sensors