UL-19 real world numbers

[Curtisjames9]

“Long time listener, first time caller” here

Picked up a new UL-19 this past fall and after running stock for a bit, started down the rabbit hole on finding a fast(er) and reliable setup.

pretty much running WOT ovals.

Here’s my data on stock boat with 4s: batteries were (2) 2s SMC HP 6500mah and (2) 2s Spektrum 120c 6200mah

SMCs
ABC 1616-17-45 (tel:1616-17-45) S&B : 49mph ~4 min runtime
ABC 1716-17-45 (tel:1716-17-45) S&B : 51mph ~ 3.5 min - desoldered motor wires
OSE CNC 4216 : 48 mph ~ 3.5 min - desoldered motor wires

Spektrums
ABC 1616-17-45 (tel:1616-17-45) S&B : 44mph ~ 4 min
ABC 1716-17-45 (tel:1716-17-45) S&B : 46mph ~ 3.5 min
OSE CNC 4216 : 45mph ~ 3.5 min


everything on 4s ran hot and desoldered several times - high amps! I’m guessing 4s would do better with smaller/lower pitch props..

After a lot of reading/research and help from Mr. Vaccaro, I went the higher voltage, lower kv route..I changed out to a OSE Raider 150A ESC, and a SSS 4074 1600kv motor on 6s. Also ordered a octura x442. Using 8mm connections on motor to ESC, IC5 connections on batteries. I also shortened the ESC wires down to about 3”.

boat has mojo turn fin and carbon tray on OSE site - empty weight is 6lb, 6.7oz after new motor/ESC


6s data:
batteries are (2) 3s SMC HP 7600mah and (2) 3s SMC HC 8400mah

HPs
ABC 1616-17-45 (tel:1616-17-45) S&B : 65mph ~ runtime TBD
OSE sharpened octura x442 : 60mph ~ 5.5min

HCs
ABC 1616-17-45 (tel:1616-17-45) S&B : 61mph ~ 5min
OSE sharpened octura x442 : 57mph ~ 6min


I found the OSE speed calculator to be pretty accurate, and according to it, would see 70mph with new setup and the 4216 or ABC 1716 props. However, with winter temps up here, the last thing I want is a blow over and a cold swim to retrieve! Gonna wait to see what speeds/temps those props produce.


overall I like the x442 - temps were never over 130 on ESC/motor - the motor bullets did get alittle hot (~190 but never melted heat shrink or desoldered). Battery connections warm, but not too hot. Was running mostly WOT until I brought it in.

I definitely fell victim to the utuber’s setups and ran those props until
I started melting stuff. From here on out, it’s gonna be smaller/lower pitches for me.. for continuous WOT I think the x442 is at the upper limit of reliability - I’d like to see what a 40x1.5 pitch or a 38x1.6 would do, but I’m also learning prop testing is expensive. Once I settle on one or two to keep, I’ll sell the others on OSE swap.


It was fun testing/collecting data- figured I’d share here in case someone else is doing the same thing- might be a money/time saver.

[Bande1]

run times are in the 90 second range to about 120 second max. you are melting things because you are dropping voltage so low the amps are going very high. you are also damaging the batteries. you run a battery to 3.7v-3.8v and stop.

so when running ovals its a 1/6th mile course with 5 laps at non-stop full throttle. plus 1-2 partial throttle milling laps. the racing orgs made it that way because thats all batteries and wiring can realistically handle. When you run the boat, simulate a race. Drive a 50% throttle lap, then go full bore for 5 laps, then do a cool down lap. then check your voltages. You will be around storage voltage at that point with the 7600mah.

that hull should be able to do around 60mph with that motor. ideally a 4092 with KV no higher than 1500kv then switch back to the 1716 for 6s. why? because 6s can put out around 3,000w sustained and that is what a 4092 is rated to handle. That would get you around the 65mph mark. again for 120 seconds of runtime.

you want some good fun? take the 4s system you removed and build a nexgen outrigger with it and you might even beat the UL-19 on 6s.

[Curtisjames9]

Thanks for the info…if I went if a 4092 motor, do you think the Raider ESC could keep up, or would I need something more robust?

[Bande1]

oh yeah. the raider can handle 160A-170A. it pushes my 4070 @ 3800w.

[Curtisjames9]

Awesome - thanks!