I don't think I have any specs on Toy 20R. LCE is showing the 20R and 22s are the same camshaft.
I could use the stock specs as a base line if I can find them.
bore 88.5
stroke same as a 22R 89mm
head cc's about 90cc but it is a hemispherical design
carb - single or duel plane ditch that 
get a good 22R carb and adapter or weber
carb CFM 22R or weber are 325ish
Intake runner length in inches about 8
compression ratio about 9 stock but put that head on a early 22r block and SHAZZAAAAMMMM
Tonight I'll see what other data I can use to get more accurate with the output.
Gnarls.
LOL all you need to know about the 20R is
1. the carbs are very anemic
2. the engines are bullet proof
3. you need a header the stock exhaust is what is called a volumetric restrictor
