Mac McLeanOxfordshire England email@example.com 6/9/2003
1938 J.A.P.type 4B 497 cc speedway engine manufactured by(J.A.Preswich of London)
The model is single cylinder 4 cycle OHV 1 inch bore 1.250 inch stroke which is close to third scale of 80mm bore 99mm stroke of the original. First run 1995.
The inspiration to build this engine was nostalgia it was the only one I used in my track racing days and I knew it well it is own design and all made from bar stock.
The carburettor is a copy of the Amal mk2 gravity fed with float chamber, main and slow running jets and slide choke with needle. The oil pump is a copy external type Pilgrim fully adjustable with sight feed unfortunately it had to be made slightly larger than scale.
The engine runs on unleaded pump gas ticks over slowly and responds to the
throttle just like the real one it also sounds like and smells like the real one
running on caster base Castrol R 40 oil.
Copyright 2003, Florida Association of Model Engineers and engine builder as noted above, All rights reserved.