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What kind of fuel pressure does direct injection
require?
Bobby
I know you're kidding, (you know how much time it takes to come up with a
new design & put it into production) but here's the other reasons for not
doing a 3.5 : 1 gear drive.
I would agree with the estimate but I don't think it makes
sense in aircraft use. Not that I'm against the HP, it's the BSFC that
bothers me. The rotary gets the best BSFC around 5000 - 5500
rpm. Go higher and it gets worse which is OK for short periods
(climb, racing, etc) but if you are going to really spend serious hours in the
air, you want the engine running near the sweet spot of BSFC. With a fixed
pitch prop, this limits us to around 7250 for top end and still cruise around
5400 - 5600 rpm. A CS prop really helps here but that sort of thing is out
of economic reach for most of us. Even if you had the 3.5 : 1 gear drive,
the design of the prop gets really funky. If you ask MT or anyone else for
a prop that works best at 1500 rpm (cruise setting with engine near 5000) they
won't have it.
The 16B plays right into our hands. If we are limited on rpm (7250 is
not TOO limiting : ), there is no substitute for cubic inches and
lower weight. Even with the 7250 limit, that comes out to ~ 280
HP. Not bad for a 150lb (bare block) engine!
Tracy
On Nov 19, 2007 7:00 AM, Bob Tilley < btilley@mchsi.com> wrote:
OK Tracy,
I think 340 HP at 9,000
is an accurate estimate.
When do we get the 3.25 or 3.5:1 ratio PSRU? ;-)
Bob
1600CC. Kind of ends the talk about direct injection. Still looks like
a 6 port but the primary ports (the small ones in the center iron) are much
bigger. With a combined end port as on Paul Yaws site, and maybe a mild
bridge port, I think 340 HP at 9,000 is an accurate estimate.
Maybe 250 HP at 6,500. Going to need three blades and 74 inches of
prop.
Where do I sign up?
Lynn E.
Hanover
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