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Anyone installed Van's Cowl Louver with a PIREP?

We put louvres on our 7 many years ago as we had some CHT issues. Worked well.

Ours were best quality from the aviation aisle at Home Despot !

Send me a PM with an email and I may be able to send a snap of what we did.

Mike
 
What is "high CHT's"?

Remember, it is not unusual to have CHT's into the 400's during climb.

Your goal should be to get them to drop in cruise. If you struggle in cruise, you might have either a baffle or timing issue.

Here is a thread about CHT and oil temp limits.

(Many pilots are running way too much advance, causing high CHT's and possible engine damage, either because they are miss-set or the timing has "slipped".)
 
Have you addressed the issue of lack of airflow to the bottom of cylinders? I had this issue at first and tried everything including what you are about to do. They helped but did not fix the problem. The problem is where the airflow is blocked at the halfway point by the cylinders and baffling coming together.... in other words it can't get below especially cylinder 2 and 3. There were a few threads about 7 years ago with many photos. Dan Horton had a great thread on this. Unfortunately, the pictures are probably not visible now. When this issue is addressed your CHT problem will more than likely be solved. Before I corrected this issue my CHTs would hit 400+ by 1500 feet! I had to step climb. Once I corrected the problem by making a channel for air to also flow beneath the cylinder.... As a test, I took off on hot summer day here in lower Alabama and climbed to 10K feet at wide open throttle. CHT max was 390 early on then it started decreasing with altitude.
Of course the other things are important as well... good baffle seals, correct timing.
 
Installed and soon to be tested

Yup installed them on our 9A O-320 and will be flight testing in the next couple of weeks.

Not sure how far down the CHT rabbit hole you're intending to venture but for the sake of setting an example how far you can go after starting with louvers...

We've done numerous mods trying to remedy our #3 CHT issue for Australian conditions including:

• Replacing all baffle seals and installing aluminium clamping strips throughout
• High temp RTV silicone sealing literally all non-essential upper and lower baffle, cylinder and oil cooler gaps
• Adhering silicone sheet to all lower baffle wraps
• Filing casting slag and cleaning out debris between fins
• Incorporating the "Dan Horton Gap" into the baffling behind #3 cylinder
• Raising the mid-point of the #1 cylinder barrel inlet ramp to be inline with the midpoint of the barrel
• Manufacturing a full sized ramp for #1 cylinder head
• Replacing lower baffle wrap tensioning lockwires with steel rods
• Closing upper cowling inlet gaps with fibreglass plugs
• Replacing FAB inlet-to-lower cowling seals
• Install cowl louvers as mentioned
• Ensuring all CHT probe adapter's are appropriately seated (they weren't upon initial inspection!)
• Replacing carby with -32 model
• Replacing all the old VDO sensors with new Kavlico types so we know the numbers are correct

I can let you know what all these mods have done collectively once we've flown, if that helps?

(Failing success next stop will be to sleeve the sump per Lyc SB-258)

Pat.
 
Yes

I put them in my O320/160hp 6A and got nothing for it. My issue like stated here was hot on climb out. It was #1 and #2 for me. Best solution for me was lower the nose. I do, and after 2-3 minutes @ 400-415 degrees, I am higher and in cooler air, can repitch or hang there. BUT....recently I cut off the "ramps" in front of #1 and #2, leaving enough to replace with pull rivets if needed. WOW ! #1 and #2 both dropped....#1 about 20 degrees and #2 about 10. I can still make them hot if I climb out aggressively. Never have I had an issue in cruise, all in low to mid 300's. My #3 is usually always warmer than others, but not by much.
 
Butch, out of interest which specific model is your Lyc? Was is ever converted from 150hp to 160hp, and which dash number is your carby? Also, would you know the fuel flow during rotation?

We became the custodians of an upgraded 160hp O-320 which had it's ramps removed and still required careful climbing as you mentioned.

Turns out the carby was never upgraded to supply more fuel WOT, which was probably hidden by the colder Canadian weather whence the aircraft came. In the Australian heat all was exposed.

A further giveaway was the fuel flow during WOT at sea level. We went from 45 to 57 lhp / 12 to 15 gph with our carby change and with it a substantial improvment in CHTs and performance (+450F to -420F during takeoff).

My apologies for the hijack, but I figure it all relates and may benefit the OP.
 
My apologies for the hijack, but I figure it all relates and may benefit the OP.

I would ask for *all* of the details around the CHT's, the engine, and the installation. The OP may be concerned about CHT's that peak at 405...or 450. There's a huge difference there, IMO.

I'd love to know what the CHT's are by cylinder and what has been checked and upgraded to deal with the problem. Are the upper ramps in place? What's the ignition system and timing? Has anyone taken a thorough look at the baffles and sealed the openings with RTV? Are the baffle seals in good shape? What has been done to check/verify the air/fuel mixture?

A picture of the baffle seals would be awesome.
 
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