OUTLAW EAGLE MANUFACTURING

[Coyotitto]

Sorry boosted but you are wrong Jesse sat right beside me on a test pass in a cx boat and wachted the the intake pressure hold 70lbs.and this boat was rock solid. As the pressure increases set up becomes more critical and it is this you have wrong.

[TOP DAWG]

have you tried opening up your nozzle just a little ?

[greg b]

Have not tried opening the nozzle Felix, maybe that's worth a try! THX!
By the way your boat looks awesome, best of luck with it!

[boosted]

[greg b]

Just my thoughts, no proof, because, unlike Rob I haven't done it yet!
I have zero doubt that 55-60 or even 70lbs. Intake pressure in the Eagle CX hulls may be the optimum balance for that hull/engine, but like Rob says, along with that goes all the setup that got you there, I'm sure it's a delicate balance, often times 10 things can achieve your goal but only one is the correct change to truly fit with all other factors
in that particular hull (even if quite similar, they are never the same) effecting performance!
Pressure cannot happen unless the area is pretty much totally enclosed, if one end of a cylinder is open it's pretty tough to build pressure, right? Same in a suction piece. If our intake pressure gauge is showing 60psi that has to mean that the ram effect of water entering the intake is somewhere near that same number. If you take the typical intake opening 6 5/8”x9” = 60 sq. in. times 60psi intake press. that's 3,600 pounds (cross section only, not total volume).
Assume in this example we have no reversion (the pump is processing all the water entering the intake) So my question is, the water we are running on at the surface is at atmospheric pressure before the boat gets there, yet as the water enters our intake it builds pressure, where exactly does that transition happen, is it well inside the suction piece (in other words if you drew a line at the grate would it still be only atmospheric pressure below the grate, or even less, resulting from the suction of the impeller ) or more logical to me it seems like that pressure would force back a bubble of pressure (not water) outside the intake, compressing the water below, therefore producing lift to some degree? If this is true I can see how it would be beneficial in a hull with the center of gravity of the hull is far towards the transom until like Boosted says, other factors are not balanced properly (and blows out). In addition to preloading the impeller like Rob mentioned.
In my hull the C.G. is much further forward and I think it will never reach it’s optimum speed with much if any lift being produced by the intake, which, again if true, I’ll have to find others ways to build speed other than high suction piece pressure.

[Arthur]

Wow, you lost me at 'just my thoughts'! I'm blown away by you're desire and passion to not only build this thing, but make it fast/work. There is no better man than RC to bounce ideas off of....you should have brought it up anyway and let him have a go at it. I hope it all comes together for you.

[greg b]

Arthur 2, you are right about Rob Chrunyk, I have the utmost respect for Rob's knowledge and achievements in racing/ boat manufacturing, he along with Tim Harding are the best there is in my mind!

[bender]

really cool boat i have been following this build for awhile now just my thoughts on what you siad i dont know about where the bowl pressure happens but wouldnt the water being suck in be under negative pressure until its compacted agianst something ? i have always imagined that the intake of a boat would have to produce more of suction to the water then a lift ? i think i understand what you are saying but it seems otherwise in my mind is all . i think of it like a shop vac sucking water out of something the hose just wants to get sucked right into the water ? anyway just my thoughts really I wouldnt listen to anything I say lol

[greg b]

Moved the engine back 6", moved the fuel back 25.5", saw major improvement in speed today with the changes! Still more improvement needed and will take some time for major fabrication changes, will keep you posted!

[greg b]

Making some progress but still quite a way to go! The other day I was running, bow was lifting nicely until I got up to 90mph then it drops pretty hard, played with intake and shoes for spoons again, then finally, finally figured out I was riding on my bowl, should have figured that out over a month ago! My shoe was raised too much and way to short so it allowed water to raise too much to soon and was really hitting bowl hard. Ran again day before yesterday with back of shoe lower and longer, wow what a difference in handling! But I'm still off, the shoe front is too far forward and water pressure bent it on my first run, put on a shoe that is not cantilivered so far forward, went out again, boat felt great, really lifting and stable then my rpm dropped from 6,000 to 5,400 then climbed back up to maybe 5,800, 5,900, was worried sick something happened to the engine so let off and headed to trailer, on previous run I had heard a noise I didnt like, turns out that was a new u-joint going out(I think). So anyway took boat home, pulled pump, driveline and intake, broke the pump down and was never sooo happy to see that I had spun the wear ring and had big chunks of nylon liner wraped around the impeller, cool, engine is fine! Was the impeller chewing up the liner that caused my RPM to drop. By the way, thats second wear ring I've spun, first was a stainless wear ring on stainless impeller but thought I could get by with it for a little while, apparently not! but second wear ring was bronze so not sure why I lost this one, my guess is after hearing the driveline noise on my first run, I reved it up pretty high out of the water just before my last run trying to figure out where noise was coming from. Better check to insure my pump shaft is straight etc etc. before putting back together.
Still trying very hard to get this thing to Lewiston!!!!!!

[TOP DAWG]

Great progress Greg. I alway drill a hole through the outside of my suction housing and the wear ring. I tap it 1/4 inch and locktite a bolt in it. You need to then clean up the inside of the wear ring / bolt to make it smooth and VOILA ! you wont spin another one. Ive seen this done on many race boats now.

On my turbine boat when we were testing, I measured 60psi of pressure about an inch ahead of the wear ring about an inch from the top of the impeller. I was also measuring the pressure at the bottom of the impeller and could see 55psi there. This was with at standard grate. I then welded some loader barrs in the grate and got a 10 psi increase on the top of the impeller and went to 0psi at the bottom. This resulted in about a 10mph gain but i can only predict will be very hard on impellers. Just something i thought id share with you. I use 3 didgital pressure transmitters to work on my setup and am really finding out alot. The third is on my bowl.

[greg b]

Felix, I'm building a loader grate now but haven't seen any others, at what angle do bars work, parrallel to suction piece roof, angled up slightly? How long are your bars? Are the extended outside grate bars slighly or just flush? The set screw on the wear ring is a good idea, I've seen this also and will do it now! I was running about .025"- .030" clearance on my impeller thinking I might go to .035" now. The best I've seen for suction pressure is 38psi on top and 18psi on bottom but with that setup boat wanted to pull pretty hard to the left. last time I was out althopugh I didn't have much of a chance to monitor it looked like I had about 27 on top and 24psi on the bottom and boat didn't pull nearly so much to left. I'm thinking and hoping pressure will go up some next time out, hope so anyway. I'm not sure just guessing boat pulled hard to left with alot higher pressure on top because of the imbalance in the bowl/ water strightner rotaing the water around behind the impeller and loading the nozzle unevenly going into the nozzle outlet. Seems maybe ideally we would have same pressure or close top, bottom.

[TOP DAWG]

The bars are installed flush with the bottom of the grate, about 3/4 of the way back and they are angled in a way to direct water at the very center of the impeller. Im sure by moving these around it would change things considerably, it will be trial and error

[eddie]

Great work Greg, this project is very cool. Do you have access to a video camera, be great to see it on the water? Also if you want you could take a few pics so we can see what your up to!

Awesome stuff!

[greg b]

Working on doing that Eddie, hopefully soon!