It does appear to match the R-type in the photo, especially the one with the round muffler.I am fairly certain the Breisch 1/2-scale is based on the Seager-Olds Type R 1-3/4 HP engine. Here is a link to Smokstak with literature and photos. I don't believe Paul Breisch ever sold a 1/4-scale version.
Thanks for that link. Very good Olds info.
It is surprising how much variation there is in the various Olds engines.
Its almost like no two alike.
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