Looking at High nose WP GP-20s vs, GP-18s and was wondering what are the main differences between them other than the number of turbo stacks. Also how difficult is it to put a Decoder in the LL GP18? Brad
GP-20 low-nose is not too bad for a decoder. You do have to mill out a spot for the decoder, and I think it's best to mill out a little space around the brush caps for the orange and gray motor leads. This site can be an invaluable help: http://www.trainweb.org/nrmrc/dcc/conversions.html
One thing that may need clarification. While the GP20 has always been a split frame mech, it hasn't always been so with the GP18. The older version has a plastic frame and lead weights. Conversion will be a little different in this case
Charger: It's relatively easy to place a decoder in the LL GP-18 split frame mechanism. Mill out the frame for a decoder preferably a Lenz mini- gold series decoder which is the smallest decoder on the market today and wire it which is straigh6t forward. Stay cool and run steam.....
Brad, GP20's were the first turbo'd 4-axle EMD with a single stack where the GP18 is normally aspirated with twin stacks. There are notable differences in the body between the pair so a GP18 will not truly represent a GP20. But.... The LL GP20 is low-nose only where the GP18 is (was?) available in both high- and low-nose. The conversion is a simple one. I have done four to date, three using a high nose from an Atlas GP7/9 and one using the high nose from a first run LL GP18. I have a page for doing this conversion. Currently it's not uploaded to the new server but give a day or two and I'll get it in place, then look at the following page; http://members.optusnet.com.au/~audiosat/modelling/howto/wpgp20.htm The DCC'ing of these has been ably answered above. edit - page linked above now online. [ January 26, 2006, 09:18 PM: Message edited by: Gats ]