Just wondering what peak TIT others get. I have the Turbo-plus intercooler, and at 32" MP, 2450 RPM and 9000 feet, the max TIT is 1625F at about 11 GPH of fuel flow. What do others get at peak, and what do you run the TIT during cruise? Specs on the TSIO-360-FB from Continental list 1725F as the Max TIT. Does anyone see the temp get that high?
I have the airflow systems intercooler & merlin
Went for a blast today and took note of the temps for you
Climb to 11500 2450@31" tit was 1480
cruised 2350@28" tit was 1425
no wind to speak of ground speed 150knots on the 530 garmin
I am a new Arrow owner and still getting my head arround everything so i'm staying full rich at the moment
Edited 2 time(s). Last edit at 05/27/2008 04:13AM by Transworld.
I fly a turbo-Arrow with a Merlyn, but no intercooler. I have a JPI with a TIT reading, and have had the probe calibrated.
1725 strikes me as very hot, and I have never seen a TIT reading that high ever on my aircraft. I thought the limit was 1650, and I don't think it has ever gone over that (at least not with me knowing about it).
I record the data from the JPI, and review it periodically to help me with engine management. I cruise at 30"/2400 rpm and see fuel flows of about 11.5-12.5 gph. I try to run about 50 ROP. The TIT typically runs about 1525-1575. I am going to start experimenting with LOP operations.
If you are running 32" at 11 gph then I would guess you are running at peak or maybe slightly LOP. Your temps seem quite high to me, and I would guess your CHT's are also running hot.
Rick,
I cruise at about 32" and 2450RPM with about 13GPH of fuel flow. This gives about 1580 for the TIT and the CHTs are all below about 325F. This is the recommended cruise setting in the POH, and it gives a good speed/fuel burn trade-off. The 11 GPH will yield the Max TIT, and if I go to 10.5 GPH I run at LOP. I am not comfortable with doing that yet, the MP drops about 2" when LOP and I do not want to burn another exhaust valve! I was just wondering what the REAL Max TIT is for this aircraft, some literature indicates 1650F, but the specs that I got from Continential's web site show 1725F (really high!). Also, what are the most common parameters for operation, and do people follow the POH or are they more conservative. Thanks for the input.
OK...I understand your question now. I thought you were cruising at 32"/2450/11 gph. Sorry.
I looked at my most recent JPI data, and at 30"/2400 the peak TIT reaches about 1565. It never goes above 1600, no matter what the mixture setting (even LOP). Now that you clarify the context, your numbers seem very much in line with what I am seeing on my aircraft.
I cruise at 30"/2400 and see fuel flows of about 11.9-12.3 gph. I would estimate I am about 25-50 ROP but it is not easy to tell exactly, even with the JPI. That seems to be a sweet-spot for my engine.
Unfortunately, I have my JPI set up such that it does not record fuel flow. That was not an option with the configuration that I wanted. I would like to be more confident of my data, and I am going to do some more test flights over the summer to try to get a very good handle on my engine temps and fuel flows.
I have a Merlyn wastegate without an intercooler in my TA. I cruise at
28 -30"/2400 and lean to 1525 TIT with CHT's running around 310. Fuel flows are 12.9 GPH. I must admit that I haven't pushed the TIT with additional leaning. Sometimes I wonder if I'll run into problems by not running higher CHT's. My engine is at 1100 hrs SFREM and so far no problems and I'm hesitant to change my settings since my engine has performed so well over the last 8 years.
Bill,
It would be interesting to see what you Max TIT would be at leaner settings. I find that I have to lean and let the turbo "soak" for a few minutes to get the final temp. At 28-30" of MP, the POH shows the %HP to be about 65%, which is great for longevity of the engine. I don't think you can hurt the engine by running it at 65%, maybe get carbon deposits on a plug? The turbo will last longer at lower temps, I just like to go fast! For some reason, every flight has to be a "test" flight where I am optimizing the engine (It's the engineer in me). If you get more data, please feel free to share, it helps to better understand the operation of the aircraft. Thanks.
jjair,
I find that 30 inches compared with 28 only gives me a couple extra knots of cruise speed and I figured that it wasn't worth pushing the engine in the long run. I have found it interesting to read what power and mixture settings other Turbo Arrow owners are using since I've been reluctant to experiment toward the leaner side. The only issues I've had with fouled plugs is with taxiing while full rich so I always lean during taxi.
Our experience is the same as Rick and Bill. We do not have a Merlyn or an intercooler, but our TIT has never been over 1600. Generally we cruise at 30"/2400 (65% power) and about 12 gph. Our experience is that anything over that will lead to cracked cylinders. I would really recommend against going over 65% power for long periods of time.
