90 mph promarine mtr build

[yeti0562]

I have been 75 on the stock electronics
120 amp esc 3674 2075kv m545 6s
had to run boat very loose for the motor to pull that prop to those speeds.
with this setup hope to run at least 90 a little wetter/safer.

4082 2200kv. t180 esc. ABC 1815 17 degree rake 6S
stiffening hull adding about 8 ounces of matting and resin.
electronics are adding about 6 ounces

between added weight and more power hopefully will hit my goal

[Tamelesstgr]

Do yourself a favor and fill the sponson tips with epoxy and the deck seam in front between the tips as well, maybe even take a look at the deck seam all around. Crashing at 90 will certainly spell disaster and possible sunken hardware mentioned above. Flotation wouldn't be a bad idea either.

[dasboata]

the best bet and what I was taught from Remy SR over 25 years ago,,is to use 4-8Lb expandable foam in the sponson tips the hard part is figuring out how much to use I have figures on that but for gas a nitro boat
http://www.fibreglast.com/product/2_Lb_Polyurethane_Mix_and_Pour_Foam_24_25/Foam?utm_source=bing&utm_medium=cpc&utm_campaign=14_Mix_%2526_Pour&utm_term=%252Bexpandable%2520%252Bfoam&utm_content=Expanding_Foam

[boredom.is.me]

Can't you just pour is layers to account for the unknown volume? And why not use the lightest, 2Lb/ft^3.

My bad, I missed the sponson tip part.

[dasboata]

Can't you just pour is layers to account for the unknown volume? And why not use the lightest, 2Lb/ft^3.

My bad, I missed the sponson tip part.

As I understand it the more density the more it floats and stronger it is

[yeti0562]

all glass matting in and tips filled with epoxy148393

[fweasel]

fast work.

[Fluid]

Depending on the motor quality, cell number and quality, and boat setup, that is probably not enough to break into the 90s. Too, the amp draw will be pretty high for a T180. I base this on SAW experience with a slightly smaller 90+ mph cat several years ago, but wasn't GPS racing which has a lower standard. The OP does have a better prop and that will help, good luck to him.

High density foam has less flotation than low density foam, but it is stronger. The problem with filling sponsons with foam is that some of them will shrink over time, pulling in the deck and/or bottom. Reinforced seams or not, a crash at 90 mph is very hard on thin glass hulls and will find the weak points for failure. Even thicker glass hulls can break.


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[yeti0562]

all electronics installed. and water lines plumbed
had to grind the bottom of the water jacket to be able to get proper alignment to stuffing tube.
waiting on new stuffing tube to finish up. 148403148403 usps shows it out for delivery