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Capt. Crash
01-31-2009, 06:24 PM
...bet that got your attention! :just-kidding:

Not really 59.4.....but here are my speeds on the 4 runs I made today. First two were on one set of packs....the last two were on the last set of packs.

48.4
46.3
49.4
47.0

I included a pic of the setup inside to include the GPS reading for the last run that was still on the GPS when I got home and turned it on. I used the set up I said I was going to use in the "Hospital Hop" thread. Gota go to the movies...more later. :banana:

egneg
01-31-2009, 06:33 PM
...bet that got your attention! :just-kidding:

Not really 59.4.....but here are my speeds on the 4 runs I made today. First two were on one set of packs....the last two were on the last set of packs.

48.4
46.3
49.4
47.0

I included a pic of the setup inside to include the GPS reading for the last run that was still on the GPS when I got home and turned it on. I used the set up I said I was going to use in the "Hospital Hop" thread. Gota go to the movies...more later. :banana:

I went through the posts and am a bit confused as to what setup yo are speaking of - please clarify as Inquiring minds would like to know!

calcagno45
01-31-2009, 06:48 PM
In his other thread he was suggested a setup for the thrust angle and depth. I believe thats what he is referring to.

Good job man!! almost at the magical 50mph!!

egneg
01-31-2009, 07:00 PM
So is it 15/16 with 1 degree?

JimClark
01-31-2009, 07:09 PM
maybe KPH not MPH:laugh::laugh::laugh:

detox
01-31-2009, 08:12 PM
Capt.

Setting the CG at 3 to 3 1/4" back from the sponson backs will get you very close. Typically on a good race boat the CG is around the center of the back of the turn fin. One of the reasons my turn fin design is swept.. allows better turning on a wider CG range.

The bottom of the rudder can make lift.. more then you think.. also remember to sharpen the rudder.. (lift lift lift)


Grim

Looks like your COG is too far forward. Your boat should be faster if you move batteries back all the way toward engine mount. My COG is dead on 3"-3 1/4" back behind sponsons as in picture. Maybe you can install your GPS in canopy opening.

Fresh New Lipo's will make it faster also. Lipo's that have been setting all winter will be slower.

Capt. Crash
02-01-2009, 09:04 AM
As posted in the "Hospital Hop" thread...here is the pic of the strut angle....how many degrees is your best guess. After I moved the prop down...this is what I had at 1 1/16" from hull to bottom of strut (table). 40X57/3 prop. Batteries were 5250 30c charged the night before and not topped off for the first set...charged two hours before and not topped off for the second set. These are new packs with 5 & 4 charges each respectively. Air temp 60. Packs were not warmed. So battery conditions were not optimal. Water condition was almost glass smooth for the first lap.

Although I'm being told here that the strut angle is way too much and the CG is off...she ran better than ever. NO HOSPITAL HOP!

CG is very close where it is now! I think my packs are lighter than most....that's why I moved them forward after seeing my boat was tail heavy.

The Montgomery Model Boat Club MMBC has a brand new member that showed me a van full of gas boats, some are hydros, and he has first FE (UL-1) on the way. (John I know your reading this....sign in and join the conversation dude!) He told me that she looked to be trimmed out pretty well for the conditions yesterday...and since she ran so well...I'm inclined to believe it.

All I know is I'm very, very close to nailing 50 mph....and yes a little tweaking may be needed but I think I am very close to race set up. Probably a professionally sharpened prop would push me over 50mph...remember I'm a newbie and that includes prop sharpening skills. Even after the last run of well over a mile...she was running very cool....100 degrees on the batteries and less on the rest....bone stock except for the prop and a thrust bearing.

I did let her rip into the 180 hairpin at full throttle a couple times just to see what would happen....and of course she scrubbed off a ton of speed but took the full rudder, full speed turns, with no problem. I did get air borne one time after crossing my wake but she landed prop down. All repairs appear to be holding up...no water came out the drain plug.

A great boat .:thumbup:

Once again my thanks to everyone here that has helped to make that possible!

properchopper
02-01-2009, 09:13 AM
Good Stuff ! Once dialed in it's definitely a fun run.
I'll report on today's run with the same settings but with the G-10 ride pads installed per DJ. After the stupid bowl, of course. :olleyes:

egneg
02-01-2009, 09:41 AM
Thanks CC for posting your setup and speeds - looks like a thrust bearing will be in my next OSE order (waiting for the cooling jacket to come in). Hopefully I will run today if the wind cooperates. My original setup was at 1" and I am guessing about 3-5 degrees with a detongued X445 and ran 44.2 mph but it was quite loose. I dropped the strut down to 7/8" at 2 degrees and used a P225s that has been detongued and back cut. I think it was faster and a bit more stable but didn't have a GPS handy. If I get to run today I will try 15/16" on the strut and see how it does.

detox
02-01-2009, 09:57 AM
Wetter on the sponsons is more stable, but slower.

I notice that all new production Maxamps batteries are water proof. There is a picture of one of their lipos setting in a glass of water on their web site.

detox
02-01-2009, 10:01 AM
BTW...how is the turn fin area holding up? Has it cracked yet?

egneg
02-01-2009, 10:10 AM
Wetter on the sponsons is more stable, but slower.

I agree but I used a prop with a higher pitch at the same time so that is why I made the statement "faster and a bit more stable". The area around my turn fin cracked at the bottom of the sponson so I went ahead and did the same type reinforcement that Darin did to his.

Jeff Wohlt
02-01-2009, 03:08 PM
It would be interesting to see if one of my wire drives is enough to take it over the edge. Or to see if that cable is holding any top end back.

That is a perferct hull for a wiredrive. Coupler and wire drive is all it needs. All else can stay the same.

detox
02-01-2009, 03:24 PM
What size wire would you recommend for the UL-1? Could you run a wire in that stock oversize tubing and teflon liner?

Jeff Wohlt
02-01-2009, 11:06 PM
I would try the .062 for all out speed. Yep, the stock teflon would be okay...would be nice to bring it down a bit. What I used to do is slide the next size inside the current teflon but I bet I can find teflon to replace the stock with a smaller dia ID.

Hydros are perfect for the wire. I just wonder if he can bring it up a notch since he is so close. That and a strut with true bearings can really help as well. Any reduction in resistance = increase in speed.

EATMYWAKE
02-09-2009, 03:45 PM
As posted in the "Hospital Hop" thread...here is the pic of the strut angle....how many degrees is your best guess. After I moved the prop down...this is what I had at 1 1/16" from hull to bottom of strut (table). 40X57/3 prop. Batteries were 5250 30c charged the night before and not topped off for the first set...charged two hours before and not topped off for the second set. These are new packs with 5 & 4 charges each respectively. Air temp 60. Packs were not warmed. So battery conditions were not optimal. Water condition was almost glass smooth for the first lap.

Although I'm being told here that the strut angle is way too much and the CG is off...she ran better than ever. NO HOSPITAL HOP!

CG is very close where it is now! I think my packs are lighter than most....that's why I moved them forward after seeing my boat was tail heavy.

The Montgomery Model Boat Club MMBC has a brand new member that showed me a van full of gas boats, some are hydros, and he has first FE (UL-1) on the way. (John I know your reading this....sign in and join the conversation dude!) He told me that she looked to be trimmed out pretty well for the conditions yesterday...and since she ran so well...I'm inclined to believe it.

All I know is I'm very, very close to nailing 50 mph....and yes a little tweaking may be needed but I think I am very close to race set up. Probably a professionally sharpened prop would push me over 50mph...remember I'm a newbie and that includes prop sharpening skills. Even after the last run of well over a mile...she was running very cool....100 degrees on the batteries and less on the rest....bone stock except for the prop and a thrust bearing.

I did let her rip into the 180 hairpin at full throttle a couple times just to see what would happen....and of course she scrubbed off a ton of speed but took the full rudder, full speed turns, with no problem. I did get air borne one time after crossing my wake but she landed prop down. All repairs appear to be holding up...no water came out the drain plug.

A great boat .:thumbup:

Once again my thanks to everyone here that has helped to make that possible!

whats temps were you runnning? can you run a full charge through the boat w/o getting too hot?

Flying Scotsman
02-09-2009, 04:00 PM
Robert, props and the driveline are the key. Very impressive results. I can not wait till it warms up here in order to test my UL-1 and thanks for the heads up from Fluid, Properchopper, Darin and many others on setups and problems

Douggie