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On my flight from Idaho to Prineville, my #3 CHT was running high. I had modified the system for diverting air, the left side was running well, so I went back to my original system on the right side. Still need to do some tweaking, but I'm happy with the numbers. The original diverters were made of fiberglass and I'm trying to recreate using aluminum to increase durability.
FYI, I have custom ram air ducts and don't use deflectors. Deflectors and dams create cooling drag. I've focused on shaping the inlet air by diverting it. More later once I've tweaked.
*More info. Using the original diverters on the right side reduced the temp on #3 by 40 F, but also dropped #1 by 40 F. Next modification will be to adjust the new right side diverters to more resemble the original left side design to reduce #2 to match #1 along with #5. I've had the 4 corners running the same temps. Now that #3 is under control and matches #4, I can work to bring those temps down another 40 F. The goal is all CHT's in the 260 F range.
Oil temps are better, but still in the 200+ F range. I've made a new lower cowl bottom to increase the outlet depth, cowl length and incorporate the exhaust cuffs. Need to install this new piece and get some new numbers before tweaking to adjust other engine temps. Trying to maximize suction from the cowl outlet.
Here's a good link to some cowl ideas I found last week, basically validates the path I'm on. Some of this stuff is in the Jabiru Install manual. Not sure how much you can trust LoPresti when it comes to reducing drag ;-)
A nice hangar came available at the Bend airport and it was too good to pass up. This reduces my drive time from 45 minutes to 20 minutes.
Live long and prosper!