hmmm
i havent taken rpm above 3k from a long time, on petrol cng n on lpg
u floor n want good avg too 
jab lpg khtm hoi na to phr 3k kiya 2k tak b ni jai gi 
u wont get any response to race n it'll just turn off, so if its giving response till 3k then its some other issue
in case if it freezes still car will turn off but after covering some distance u can shift back to lpg
also if it ended at 84 to phr to kuch zaida hi daba k chalatey rahe ho 
even i got avg of 9.71 first time dont know wid any kg remaining or not but that was wid ac n no setting done, n here u did ur own setting driving a manual n got an avg of 8.4 lol
petrol dalwa kr bhagao to ek din b na chaley 
get proper setting done or re tune urself considering that its lpg n not cng