You're asking two different things. The best climb rate for almost every prop plane we have in the game is between 150-170mph indicated airspeed (IAS). You are getting 1500 fpm climb in a hog at 220mph IAS. That is nowhere near it's best "climb rate" (sea level), but I suppose it's a fairly decent climb rate if you want to maintain decent manuevering speed.
But my advice is, throw that quote you have out the window. Go with what bozon said just above.
If there's someone with an alt advantage who knows what he is doing, you're only doing him a tremendous favor by going towards him in a shallow climb, even if you are maintaining 220 indicated. The key is to get the alt monkey to dive, and if he's novice, ideally to equalize his E state with yours. No self respecting alt monkey would knowingly make this tradeoff, but the trick is to equalize E states without him realizing.
Know your plane, and your adversary's. Does he dive well, or compress easily? If your plane has better manuevering at high airspeed, show him your six, let him get within 3k. Start a shallow dive. Let him close, within 1.5k or so, steepen your dive. Let him maintain closure rate, thinking he'll get a shot. Use your superior high speed manueverability at about D600 to easily evade his shot attempt (but don't blow too much E!). Reverse into him as soon as it is evident he is pulling up and over. He's gone from having tremendous E advantage, to having maybe 20 or 30 mph (the slight discrepancy still being by virtue of your evasion roll), your zoom potential nonwithstanding. Most players in this situation, as your enemy, will panic now, climbing and seeing you maintain constant distance on their six. They will Split S, or some other poorly thought-out move, and you have won the fight.
The numbers in my example are not exact, but you get a feel for the skill level of the enemy pilot, and a feel for the situation. Don't get so caught up in charts. Data helps you determine what type of fight to make it, but it never alone wins the fight.
Good luck.