LOP FF versus GPH for TSIO-360

[Pinecone]

I looked and found numbers for FF versus HP for several flavors of NA engines, but not the turbo engines.

Does anyone have the number for TSIO-360, specifically -SB?

[Will.iam]

I have the MB engine so 10 hp less than yours and i use 9.5 gph @ 25” MP and 2500 RPM. That gets me 25 degrees LOP and works well for all altitudes up to 17k which is the highest i have flow so far. Basically any FF in the 12’s is bad in the red box zone. You could get away with 10.5 FF and still be LOP. I have found the closer you can get to peak egt on the lop side the better power but temperature of your TIT or CHT will limit you. Back in the certification days mooney was ok with 1650 TIT and 420 CHT. We now know that shortens the life of the turbo and cylinders when run that hot. So i would experiment starting at 9.5 ff 25” and 2500rpm as a base point and go from there. That gives me 1550 TIT and 380 CHT in the summer 90 degrees with cowl flaps closed.  When it’s 100 degrees outside and I’m still low E. G. 3000ft i have to open the cowl one marker to keep the CHT at 380. In the winter i can go 10.5 FF and cowl flaps closed and still keep CHT below 380. Once you know what stabilizes at the cht you want, write down those numbers to goto right away when you level for cruise. No need to do a lean find and drag through the red box area anymore. 

[Marc_B]

@Pinecone From what I've learned on the LOP side the fuel is the limiting factor.  So for the compressions on the TSIO360SB with 220hp you can use 13.7 to calculate the FF using %HP * max HP / 13.7 = fuel flow in GPH.

i.e. 0.65*220/13.7 = 10.4 GPH for 65%HP LOP

of course this doesn't determine how many degrees LOP you are and it just applies if you are on the LOP side.  The multiplier varies based on the compression, but 13.7 is good for TSIO360.  Add more MAP (air) and keep FF constant to go deeper LOP.  Mike Busch and Savvy have some good videos/articles on this.

[carusoam]

Hmmmm….

You can probably get the data from Continental….

Then adjust it to meet your needs…

 

Or…. You can probably get it from MAPA, their PPP document…. And go to a great weekend gathering….

 

Or… Check your POH to see if they printed it in there….

 

My usual numbers for LOP vs ROP for the IO550…. Cruising WOT at 12k’…. ROP around 15 gph 175kts, LOP 12.5gph  165kts (rough numbers)

In this case LOP is very close to peak….

There are a few discussions around here for operating TC’d engines LOP… very interesting details there… find @jlunseth… one of my favorite authors on the subject….  

Best regards,

-a-

[carusoam]

If you want to edit the title…

Find the edit buttons at the top of the first post… the title is attached to it…

Best regards,

-a-

[Pinecone]

10 hours ago, carusoam said:

If you want to edit the title…

Find the edit buttons at the top of the first post… the title is attached to it…

Best regards,

-a-

Happy?

 

[Pinecone]

14 hours ago, Marc_B said:

@Pinecone From what I've learned on the LOP side the fuel is the limiting factor.  So for the compressions on the TSIO360SB with 220hp you can use 13.7 to calculate the FF using %HP * max HP / 13.7 = fuel flow in GPH.

i.e. 0.65*220/13.7 = 10.4 GPH for 65%HP LOP

of course this doesn't determine how many degrees LOP you are and it just applies if you are on the LOP side.  The multiplier varies based on the compression, but 13.7 is good for TSIO360.  Add more MAP (air) and keep FF constant to go deeper LOP.  Mike Busch and Savvy have some good videos/articles on this.

Thanks, that was what I was looking for.

 

[carusoam]

15 hours ago, Pinecone said:

Happy?

 

That worked really well!

-a-