#26
IP: 71.253.254.56
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Yeah,,,,,
maybe one of those little squirells with a life vest
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel |
#27
IP: 71.253.250.181
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New Pic
Yesterday evening cruise
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel Last edited by Ball Racing; 11-21-2011 at 07:29 AM. |
#28
IP: 148.170.241.1
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Damn, dude, that boat is just perfect! Absolutely beautiful.
Nice pic - it really shows her sweet lines. I am a total sucker for the traditional bay-built deadrise. And you totally nailed it with that one. Makes me want one just like it! I might want a little pilot house on mine...
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- Bill T. - Richmond, VA Relentless pursuer of lost causes |
#29
IP: 206.125.176.3
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Looking good!!
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-Shawn "Holiday" - '89 Alura 35 #109 "Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!) |
#30
IP: 72.83.115.32
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Sweet!
In addition to the great subject matter, the person behind the lens really knows how show it off. Masterful use of depth-of-field.
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@(^.^)@ Ed 1977 Pearson P-323 "Dolce Vita" with rebuilt Atomic-4 |
#31
IP: 71.253.250.181
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Video!
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel |
#32
IP: 96.228.21.70
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Suh-WEET!!
Man, that boat looks fantastic. My only complaint is I couldn't hear the A4 enough over the other boat's motor. But she looks great. How does she handle a chop? Have you had her out in anything like that yet? Looks like a right stout boat.
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- Bill T. - Richmond, VA Relentless pursuer of lost causes |
#33
IP: 71.253.250.181
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Seems to like the chop, just chug on thru it..
I was in wome white caps the other day, 20mph wind at least 2+ footers, just making spray, and ride on..(you can get wet doing that ) Every now and again when you found the right series of waves you could hear the prop maybe slip a little, then just go to the next set.I basically could go full throttle into the seas I turned around and following seas are not as fun, I decided to stay at hull speed, except for when you 'surfed" down a sea and almost doubled your speed. But you have to counter steer, and watching water pushing up at the stern , and feeling the boat get shoved down,,,is not as much fun as head into.. I know, that I don't want to be in the boat, in the weather it would take to dip the bow........ Or rather the boat can take more than I can
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel |
#34
IP: 74.203.131.26
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Great job man!!! I'm a builder as well...I wonder if you did a build page anywhere? I hang out at Duckworks and the huys there would love this boat!!!
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My "other" Boat: |
#35
IP: 206.125.176.3
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Daniel,
So..do we have a tach on this thing? What RPM are you up to with your latest improvements to achieve 13 MPH?
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-Shawn "Holiday" - '89 Alura 35 #109 "Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!) |
#36
IP: 71.253.250.181
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2,550 RPMS On my teleflex brand tach.
Thats with a old design 3 blade 11x7 prop. I want to try a 3 blade 11x6 Michigan Dyna Jet that should put me @ 2,800 RPMS which I think would be plenty.. I feel I need to get higher into the rpm band to get more HP, right now I am only using 20hp. 3,000RPM is suspose to be 25hp. To run like I was in that video, was MAXED Out, and I only run it like that for maybe 4 minutes at the time before I lift back to hull speed. I don't want to burn the motor up. It has more throttle lever left, Just can't get more rpms. It take a rich setting to run those max rpms. If I idle around for more than 5 minutes with that power setting she smokes badly from the extra fuel.
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel |
#37
IP: 148.170.241.1
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Which makes me wonder - what is the max RPM that the A4 should be run at for any period of time?
It really doesn't seem like a very high-revving engine to me, so I'm a bit paranoid (maybe overly so) about revving it up too much. In my recent test-running, I will give the throttle a little blip to give it a quick rev, but only for a second or two. Then I quickly bring it back down to idle. Like I said, maybe I'm being overly paranoid, but I don't like to rev it too high - although the engine does seem to be very stoutly built, it also doesn't seem like it was meant to be much of a high-revving engine - certainly not for any period of time, anyhow. Maybe a short burst now and then. Eh?
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- Bill T. - Richmond, VA Relentless pursuer of lost causes |
#38
IP: 199.173.226.236
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My original A4 ran 100% throttle from Cape May to New York and did fine.
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#39
IP: 148.170.241.1
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Quote:
Also - I note you say your "original" A4 - is that because you had to replace it after that trip?
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- Bill T. - Richmond, VA Relentless pursuer of lost causes |
#40
IP: 199.173.226.236
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I had no tach them but I would guess around 2700 RPM +/- a hundred or so.
The engine lasted a long time after that, but salt water ate it eventually. A4s don't wear out for the most part, they rust out. I am on #3 right now I expect this one to be good for at least 20 years. #1 1973 to 1994 #2 1994 to 2011 (not a very good one when I got it) #3 2011 to ???? My engine use is around 100-300 hours per year. |
#41
IP: 128.154.211.53
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Although the specs list the max RPM as 3500 (??!!), in our recent meet-up with Hanley, Don Moyer said the engine is happiest running about 2000 to 2200 RPM. Running above that for long periods of time puts a lot more stress on the engine.
I recently measured my back pressure, and under load it begins to go up rapidly above 2000 rpm. It's a concern to me, as I'm usually running at 2400.
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@(^.^)@ Ed 1977 Pearson P-323 "Dolce Vita" with rebuilt Atomic-4 |
#42
IP: 71.253.250.181
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Is there a backpressure point, that has shown damage?
My exhaust is 7 foot long straight shot after riser-water entrance, no muffler. The more rpm, the more air in, the more has to leave, the higher the rpm the more HP made, so the more btu's made, the greater volume of spent gases, so all those things will make for more pressure in the exhaust, but that is relative to the rpm curve, and all makes of engines in general. I thought the exhaust back pressure gauge was just to make sure the exhaust wasn't rusting up, and collecting minerals, and salts? In the auto style engine world, to low of rpm, with lots of throttle, will just burn it up, and wear out the rod bearings. higher rpms with less load is better than low rpms and high load..
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel |
#43
IP: 128.183.140.38
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According to Don, anything over 2 psi for extended periods is a cause for concern. But rather than hijack this thread, I'll start a new one on backpressure.
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@(^.^)@ Ed 1977 Pearson P-323 "Dolce Vita" with rebuilt Atomic-4 |
#44
IP: 206.125.176.3
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Daniel, thanks for the info. I, too, have always wondered if there was any real reason to try to get the motor to its 3,500 max RPM, & it sounds like there isn't. Us sailboat guys have the same issue you are noticing that there is xx amount of throttle and that is as fast as it goes, since we are obviously limited by hull speed. When the prop & hull are clean, that isn't very much..maybe 35% or so and after that she just gets noisier from the throttle being opened farther & more fuel being jammed down (up) its throat, but no more RPMs.
I know I don't go spinning my car up to it's 8,000 RPM redline every day. At 11+ knots I wonder about a bigger intake horn and maybe some ram air for your A4!!
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-Shawn "Holiday" - '89 Alura 35 #109 "Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!) |
#45
IP: 199.173.226.236
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AFAIK if you want to get useful work out of an A4 in the 3000-3500 RPM range, you need the reduction gear.
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#46
IP: 206.125.176.3
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joe, I think you're right, but I'd be afraid the motor would self destruct if it spent any length of time at those RPMs.
Anyone wanna try an Indigo prop on their 2:1 reduction drive?
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-Shawn "Holiday" - '89 Alura 35 #109 "Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!) |
#47
IP: 71.253.250.181
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High Rpms
Yeah, for you guys that may have to cruise for hours on end,
and hull speed can be acheived at as little as under 2,000 rpms for some. There is no good reason to want to buzz it to the moon. You want it to last, and be reliable. But,,,, Now I guess I want to "hot rod" it a little, as most of the places I plan on going are under 5 miles away, I feel I can risk more rpms, as I will not be doing it for hours on end. I can go 5 miles in under 30 minutes. So even at WOT thats only half hour at the time. So one hour a day of run time under those conditions max. Then lots of time at hull speed just looking good, and cruising.... But speed is like most any drug, you get some, you want some more, then you want a little more, then a little more etc.....
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Tyring to keep the Bay's Wooden Boat's history from dying off completely. Daniel |
#48
IP: 199.173.226.236
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I doubt it. 30 HP from 60 cubic inches at 3500 RPM is not exactly "highly stressed". Going to New England in flat calm, we left Cape May, put the throttle to 100%, and added gas underway all the way to New York. No harm at all. When I was at flight school the airplanes pretty much all got flown at "rental power", which is full throttle, and they lasted their 2,000 hours between overhaul with no issues.
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#49
IP: 151.200.26.6
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Joe, I come from the 100 HP per litre camp. My current every day car is a 2007 Civic Si that makes 197 HP from a 2.0 (rounded up from 19xx)cc motor, and my "project car" 1991 Civic has a Japanese spec motor that makes 130HP from 1.6 litres.
So...as you said, after a little bit of math, 30 HP from 60 c.i. is not much. Daniel, go for it...let's hot rod that bad boy! (just remember it only has two bearings!!!!
__________________
-Shawn "Holiday" - '89 Alura 35 #109 "Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!) |
#50
IP: 96.228.21.70
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Let's keep in mind the significant differences between the Honda Civic engine and similar more modern engines and the Atomic 4. Just because an engine is similar in displacement to another doesn't at all mean that it is deisgned or even capable of putting out similar HP.
As already has been pointed out, the A4 has an unsupported crankshaft - only two bearings, one at each end. Second, and significantly, the more modern engines are overhead cam engines, which are much higher-revving than our old flatheads. Another issue is stroke vs. bore - a lot of the modern OHC engines are oversquare, with a very short stroke. And on and on. Although the Atomic 4 is a robust wee beastie, methinks you might be asking a bit much of it to try to get anywhere near 100 h.p. out of the poor devil!
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- Bill T. - Richmond, VA Relentless pursuer of lost causes |
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