We fly our non turbo 64 PA30 @11.5 to13.5+ @ isa m.p. and 2450 rpm avg burn +-16 gph @75/100 rop highest cyl temp 375
Any ideas how much Gami injectors/fine wire plugs (champion or Tempest??) will reduce our fuel burn, seems like down
low we might burn less and up high we could run hot @ Lop, We do have a Edm 760 ff ect + wow cowls a little extra range is
what we're looking for with 105 total of fuel .
Thanks for your input
Tom c.

Deleted... better info below

Tom,
At those power settings, the ROP/LOP arguments aside, leaning to peak will actually cool your CHTs. It will also set you down in the 12.5 to 13 GPH total burn. Play with your RPM and you may find some more fuel savings without much speed loss.
-Zach

Zach is correct, based on my experience. I lean it back to peak or as lean as I can go and still be happy with the feel of the engines. You can't push the CHT over limits when you are that high as the engines are only capable to maintaining 65% or less. I have gotten the burn down to 11gph at 16,000.

Kristin

Ill add that having fine wire plugs seems to have a positive effect on how far you can lean before you get into engine roughness. Gamis also do a similar thing by matching the cyl fuel to air flow so they all basically hit peak at the same time, so the engine just looses power, it doesn't get rough first.

-Zach

James Zack Kristin
Thanks for your reply, Kristin what are your power settings alt + TAS @11 gph also do you have gamis and or fine wires,
Due to optimal valve timing + good balance my sweet spot on the props is 2450rpm @ alt gives me a TAS of 190 mph also does anybody know if champion/tempest fine wires are of the same quality?
Thanks tom c.

IIRC, I was getting about 17" MAP at 16,000 and 145 KTAS. I do not recall the OAT. I do not have either fine wires or GAMI's.

Tom,
That's great if that works for you, I just bring up the RPM thing, because horsepower does not directly translate to thrust etc, and if you are looking for range, you might find lower rpm may give you a better mpg with a slight speed sacrifice, equaling to better still air efficiency.
Zach

At 16,000 I'm doing about 170 to 175 TAS depending on OAT. Of course, that's with the turbos dialed in to 75%, and I'm burning 9.8 to 10.0 GPH per side ROP, but you can't have everything!

Jay

Nearly doubling the fuel flow for an extra 30 knots doesn't seem like the greatest of trades. Now if you are up and FL200 and getting tailwinds or staying out of the ice, then the fuel burn is a bit more worth it.

 

It is hard to resist when you have the speed at your finger tips.