Wanted to share my experience running a big bore ,86mm pistons stock stroke 885cc in my Proforce . I got 65hours out of this top end running up and down the river which is the best I have gotten.This setup gives me nearly 11gallons of fuel and 3hours run time nonstop. Anyway I screwed up and may have put some 87octane gas in it and noticed my spark plugs had loosened up and knew I had damaged it. I usually run half Av gas or a gallon of 110 in a 5 gallon can mixed with 91 octane ,I have run straight 91 without issue. I run TL Zeel on the Wax curve and believe this ignition has saved detonation and runs amazing. My compression is 160psi and I have a .025 base gasket which gives me .050 squish.You would think this setup would be safe from detonation but it is Not. The pipe I run is a lay down TNT V3 race spec and has a 2” stinger and I love the power this pipe makes the midrange is Very Strong. I’m running a Kawi 145 skat setback with a 10/18 prop which spools up quickly and pulls ok if I want to hold it wide open for a decent top end. My carb is a 49 ATP Dasa intake ,V2 reeds 2.5ns 170m 130p 95g 1.5 turns out both high and low. I think the pipe makes a lot of power at the price of reliability and would like to hear other’s thoughts on this subject as I have gone thru a bunch of pistons learning about this. I have ran dual 48s and 44s the results are the same I think I’m just on the edge performance wise. I will post some pics of the cylinder it’s a big bore sleeved 62t that was port matched by a machine shop. It was a BCW race cylinder that I wanted to bring back to life but maybe the exhaust ports are tooo big and the rings are just going to catch anyways.