check my numbers

I took a snapshot of my EFIS today during a flight, leaned-out in cruise condition. I was at around 4500 ft. Could you guys have a look at my numbers, particularly temps, and see if they all look reasonable? It's an RV-9A, Carb O-320 (160hp) with a FP (catto) prop.
(note: my fuel flow is reported in LPH and 30.5LPH is 8.05GPH.)
I wonder whether to be concerned about the temps on Cyl #2 - coldest CHT but hottest EGT (EGT spread over 100 degrees).
Thanks!

Can't see OAT, but looks good to me. As I understand it, EGT is highly dependent on probe placement and it is very hard to get them exactly in the same place on each cylinder. Thus, chasing EGT spreads is not very worthwhile. The main value, aside from help with leaning, is when you notice something different than normal for a particular cylinder.

PS... I wish my CHT spread was so good. Usually 30-40 degrees for me!

Looks reasonable to me, but I'm new to this and what do I know. As far as I know EGT values vary upon installation, and there is no limit just a value. What are your peak EGT values for each cylinder? How much below peak EGT are you on each cylinder? I'm guessing #2 and #4 are much closer to peak EGT.

Just for reference I've played around with LOP in my 7 with an O-360 and dual EFII ignition. I cannot run LOP at full throttle settings, my EGT spread is too far apart. My #4 cylinder will be 120* LOP when #2 is nearing peak EGT. However when I pull the throttle back my EGT spread is within 20-30 degrees and it seems to love LOP around 55-65% power up to 120* LOP on the leanest cylinder and 150-160 knts TAS at 7ish Gallons per hour. CHT's are generally balanced around 330. I've also seen 340-350 CHT's at altitude in hotter temps and 290-300 in cooler temps. At full throttle my leanest cylinders are also the hottest, go figure.

and 150-160 knts TAS at 7ish Gallons per hour

Click to expand...

Man when I head numbers like this I get jealous. As you can see in the photo I'm only making 145 KTAS on over 8GPH! Of course this is only at 4500 ft, and it's -9A.

Phil your numbers all look normal to me. I would never compare one person's quoted numbers to your own. It will just frustrate you. I will say my numbers are pretty close to yours. I flight plan for 145KTAS @ 7.3gph @ 8500msl. I usually make those numbers. Down at 4500, I'll bet I am around 8gph. Up high though at 11500 I see about 6.5 or so.

I would not worry about your temps. They look fine. Mine are all over the map! I have a similar cylinder that runs cool on the CHT, but hot on the EGT.

prkaye said:

Man when I head numbers like this I get jealous. As you can see in the photo I'm only making 145 KTAS on over 8GPH! Of course this is only at 4500 ft, and it's -9A.

Click to expand...

Phil,

Don't be jealous. Your RV9a o-320 get's better economy at any given speed (you are able to achieve) than that of an RV9a o-360 no matter what anyone tells you. You may not be able to go as fast or climb as fast, but you are getting better fuel economy.

Very close to my numbers

I would be very close to your numbers at those conditions. My typical cruise at 4500' , 2500/23+ would be 142- 145ktas. If I were burning 8gph my CHTs would be close to yours, maybe a tad lower due to the SJ plenum.

Typically I would be 40 -50 LOP at that altitude burning around 7.3 gph. At that LOP point, my CHTs would run 300-335 depending on OAT.

I can't speak to the one outlier EGT. I assume you've tested the probe.

Yep

+1

Those numbers very close to mine in a 9A with IO-320.

My EGTs a bit closer together but CHTs a bit more spread. I think the outlier EGT is probe position as mentioned, as long as it is always the hottest (except when going lean).