looking at overhauling my IO-360-a3b6D or upgrading. wanted opinions on both best course of action, and shops. i have proposed a couple ways id like to proceed.
1) upgrade to the IO390. this is top choice. Mainly because the prop purchase isn't that big of a deal. i would overhaul my prop anyways at major OH, so the price delta isn't THAT big. The main benefits of this route is roller engine, and dual mags. i hear lots of no performance gain this way, but both the cirrus guys (new sr20s have the IO390 instead of the conti IO360), and the Glastar guys say there are considerable gains. my main concerns on this route. Very limited data on this in the field from what i can find. I would love to see someones engine data from something like a JPI so i could see a few flights such as what the CHTs and fuel flow looks like. also would like to see some climb performance info. other concerns are engine longevity, and cylinder costs. would need pointers on a shop to complete this upgrade. G&N basically said they haven't done one in years, but would email me info. That was 10 days ago, and haven't heard from them again. not exactly confidence inspiring.
2) overhaul exchange of my d model engine to one with split mags. i like this option because i like the redundancy AND i want electronic ignition. I would like to go to shop that has done the swap before a few times. if you have gone this route via a shop you liked or didnt like i would like to hear opinions.
3) just a simple overhaul of my D model. looking for opinions on shops. so far a have a quote from lycon (top choice, but will take some time. can do an OH exchange), premier engines in troutdale (wont do an exchange, just wants to OH mine, will take up 16 weeks. too long), and firewall forward. after talking to FF, i really liked the guy, but a search on here revealed some horror stories. place im buying the place from, all American, recommended Jewell. i hadn't heard of them. experiences would be helpful here. I am pretty particular on my engine, so a well balanced engine with minimal vibration defiantly appeals to me, lycon seems to be the go to for that type of build (port, polish and balance)
Let me know your thoughts. TIA!