I'll jump in here and add my $.02, like it is worth that. The IO 360-M1B is a parallel valve engine but uses the forward facing sump. It is what I am planning on running. The fuel savings is great but also I just don't like the snout.cjensen wrote: A parallel valve 180hp injected Lyc uses hot air. So does the carb'd 180hp Lyc. 180hp is 180hp, carb or FI. Better distribution of fuel with the I engine is the advantage there. You may burn a half to one gallon an hour less with FI, but you have the same power.
CJ
Brad, yah...RV7Factory wrote:Let me confuse the issue further... just because it is horizontal induction, does that also mean it is "cold"? At one point I thought they were one and the same, but I seem to recall someone telling me they weren't.
BTW... I too dislike the snout! No snout for me!
CJCJ, no offense taken bro! I just like to do the same! Sorry, I was being a little wise a$$ie earlier...captain_john wrote:
Chad, you do make me smile! Sorry if I offended you. I just like to joke around (as you know).
How are you going to really dyno test cold air induction in a test cell to verify an 8 hp gain and attibute it to cold air induction?
The Grumman guys have a cold air system for carbs and they don't see much of a gain in that system either.
No doubt, you CAN get 180 hp out of a carb or FI. It is going to be easier to do it with a FI, all things being equal.
Besides, any engines actual output will vary 5% from day to day depending on conditions.
From a practical aspect, an engine is an air pump. When you have more precise fuel metering, you can get a more accurate (ideal) 1:14 fuel/air ratio. When this burn is done consistently and precisely, you WILL move more air and subsequently, make more power.
IF (and this is a big IF) you can get a carb to do this ALL THE TIME (and you CAN'T!) they are equal.
Soooo, a test cell is one thing and actual stick it in the airplane and fly it is TOTALLY another!
Bottom line, start off with as much power as you can, because it WILL deteriorate with environment, setup conditions and accessories.
There is no replacement for displacement, as it is all about moving air! Start big, as there will ALWAYS be losses!
Does this make sense?
BTW, I don't dislike the snorkel. I want an alternate air system in the event of unanticipated icing of the airbox. Kinda like what Pipers do. You know, taking it from inside the cowling. Not that I plan on using it... just like the heated pitot tube.
No snout for you! Come back, one year!RV7Factory wrote:Let me confuse the issue further... just because it is horizontal induction, does that also mean it is "cold"? At one point I thought they were one and the same, but I seem to recall someone telling me they weren't.
BTW... I too dislike the snout! No snout for me!
Jim, no problem! I can!jim_geo wrote:Can anyone give me a before and after on porting and polishing.
CJ
Except if you put a cold air sump on the parallel valve engine, with a forward facing fuel injection. Then it is the same intake configuration as the 200 hp angle valve engine but without the angled valves and extra weight of the counterbalanced crank.cjensen wrote:
A parallel valve 180hp injected Lyc uses hot air. So does the carb'd 180hp Lyc. 180hp is 180hp, carb or FI.
This is exactly what I have been talking/thinking about!Wicked Stick wrote: Except if you put a cold air sump on the parallel valve engine, with a forward facing fuel injection. Then it is the same intake configuration as the 200 hp angle valve engine but without the angled valves and extra weight of the counterbalanced crank.
I think I ended up with around 190 hp in the test cell at Mattituck by going cold air sump, 9 to 1 pistons, electronic ignition, and the Red/Gold package.
I'm thinking once it's hooked up to the airplane with the 4 into 1 exhaust and a possible ram air setup, I might see close to 200 hp without all the weight penalty.
And the proposition here is that with FI you can get more precise metering than you can with a carb? I would agree with automotible technology, but not aircraft technology. GAMI has made a whole business out of the fact that most aircraft injectors (in reality just a nozzle that wees fuel out of its end) are not acuratley flowing matched volumes. Managing 4 uncontrolled nozzles would be much harder than managing a single carb jet me thinks.captain_john wrote:...
From a practical aspect, an engine is an air pump. When you have more precise fuel metering, you can get a more accurate (ideal) 1:14 fuel/air ratio. When this burn is done consistently and precisely, you WILL move more air and subsequently, make more power.
IF (and this is a big IF) you can get a carb to do this ALL THE TIME (and you CAN'T!) they are equal.
I would think that 4 injectors that aren't flowing matched volumes could easily be equivilent to a single carb jet as far as distribution goes, since with the carb, you then have to rely on the in intake manifold to distribute the fuel evenly to all cylinders. During this time the fuel may loose some of it's suspension in the air, causing it to burn less efficiently.Spike wrote:And the proposition here is that with FI you can get more precise metering than you can with a carb? I would agree with automotible technology, but not aircraft technology. GAMI has made a whole business out of the fact that most aircraft injectors (in reality just a nozzle that wees fuel out of its end) are not acuratley flowing matched volumes. Managing 4 uncontrolled nozzles would be much harder than managing a single carb jet me thinks.
