From:Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf OfJerry Hey
Sent: Wednesday, March 23, 2005 8:12 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: fuel injector size, and
redrive losses
Ken, after spending the day calculating injector sizes, I ended up
coming to the same conclusion that you did. The Ford 42 lb are perfect for my
application. P.L. recommended 50 lb injectors but for 225 hp they are too much
in my opinion. Unfortunately Ford Racing is out of stock. Damn. Jerry
On Tuesday, March 22, 2005, at 06:06 PM, kenpowell@comcast.net wrote:
Jerry, the Ford injectors are not directly compatible. Here are
the details:
ENGINE SIDE FUEL RAIL SIDE
Mazda 0.65 (with the FAT Mazda
rubber ring)
Note that the electrical connector is the same (center spline
top/inside and center lower outside). So, the Ford injector will hook up
electrically but the fuel connectors must be different.
-------------- Original message --------------
> Ken, are the Ford injectors interchangeable with the stock Mazda
> injectors as far as size, plug and so on? If so, do you have a
part
> number? BTW sorry but there is no way you can run a p port at 7500
> rpm and only get 225 hp. Can you accept 240? Jerry
> On Tuesday, March 22, 2005, at 03:48 PM, kenpowell@comcast.net
wrote:
> But this graph was for a carburated engine so it really
> proves nothing. Besides, the engine only needs to be as rich as we
> want to run - you can't hurt the engine by running lean (I know,
if
> you run it into the trees on a 100 F. day that will HURT it!!!). I
> have not seen any graphs showing power improvement beyond 0.6 on a
NA
> engine and with very little to be gained by going beyond .55. If
> anyone can educate me differently please do so (no kidding, I'm
trying
> to learn). I'm planning on using 42 lb Ford injectors for my
P-Port
> motor, if this isn't enough I want to know (planning on 225 HP at
7500
> -------------- Original message --------------
> v\:* {behavior:url(#default#VML);} o\:*
{behavior:url(#default#VML);}
> w\:* {behavior:url(#default#VML);} .shape
> {behavior:url(#default#VML);} st1\:*{behavior:url(#default#ieooui)
}
> you sure youÌre allowing yourself enough margin on the top end by
> using .55 bsfc. This chart (snitched from the other list)
indicates
> that .55 is about right up to around 7500, but at 8000 rpm bsfc
will
> be up around .60. What does that do to your hp numbers?
> aircraft [mailto:flyrotary@lancaironline.net] On Behalf
> Sent: Tuesday, March 22, 2005 2:25 PM
> To: Rotary motors in aircraft
> Subject: [FlyRotary] Re: fuel injector size, and redrive
> Times New RomanRC Engineering's calcs show
> that you are good to 302 HP at 43 psi fuel pressure, .50 BSFC, and
> 100% duty cycle. Of course you can't run the injectors at 100%
> (except maybe briefly like a drag race, not applicable to
aircraft).
> So at 80% duty cycle the 38 lb injectors should be good for 242
HP.
> Enjoy your idle!!! Your injectors are big enough unless you P-Port
> and turn at least 8000 RPM.
> Engineering's calc shows the same as the fuel calculator that I
> posted the other day. Four 38 lb/hr injectors, at 80% duty cycle,
.55
> BSFC, should be good for about 220 HP at the flywheel. I imagine
that
> will be enough for the current engine, but not by a wide margin. I
> plan to run this engine as high as 8000 if I can, though I'll be
> amazed if I can get beyond 7500. Don't need no stinkin' P-Port for
> the fuel spreadsheet that I posted (stolen) the other day, it
gives a
> HP figure for the flywheel, and rear wheels. The estimate for
> the power loss due to a manual trans and diff is 15% on this
> spreadsheet. Anyone know what this amounts to for our redrive, and
> ArialFFFF,0000,0000Cheers,
> ArialFFFF,0000,0000Rusty
> (hoping Ed out types me)