Rx7man
Cattle Rubbing Post
I did a Jred 920 for a friend, he had a 920 and a 920 super.. I put the super jug on it and reworked it.. he just loves it now.. he was cutting big poplar with a 24" bar and said he could just dig the dogs in and reef on it and it would throw chips like a beaver... the Supers have nice transfer ports to work with, I cleaned up the piston windows, etc..
Here's the 920 vs reworked 920 super jug from those saws
I calculated the stock timings at 105* exhaust, 124* transfer, and 70* intake for durations of 150, 112, and 140 respectively with a 19* blowdown
The ported saw had 101/122/78 for durations of 158/116/156 with 21* blowdown
It cackled nicely across the shop floor
Here's the 920 vs reworked 920 super jug from those saws
I calculated the stock timings at 105* exhaust, 124* transfer, and 70* intake for durations of 150, 112, and 140 respectively with a 19* blowdown
The ported saw had 101/122/78 for durations of 158/116/156 with 21* blowdown
It cackled nicely across the shop floor