42" Tunnel

[Peter A]

I just picked up a 42" tunnel yesterday. I will post pics tomorrow. It has an older version Castle 2028 780kv motor and Swordfish 300A esc with the ali case.
Question. Is the motor better used on 8s or 10s for oval racing? It says 30k rpm max on the back. Also what is the best prop size range, the boat has an X457 with it.

[RaceMechaniX]

Hello Peter,

I have run a 2028 Castle in a similar size cat on both 8S and 10S. Both work well. 8S will require gas size props in the 65mm range. 10S will run 50-60mm props depending on blade count and pitch. I found low lift Octura X series 3 blades work nicely on Aeromarine cats. Very smooth and efficient with minimal bad handling behaviors. I think my preferred prop was a X457/3. If you have both 8S and 10S batteries, try with 8S first and the 457 prop you have to get a baseline and measure temps. Then try 10S.

[Peter A]

Here's some pics. Does anyone know what the hull is?

20200806_170717.jpg20200806_170722.jpg20200806_171522.jpg

I found the usb link and cd for the esc too in the boat.

[Peter A]

Hello Peter,

I have run a 2028 Castle in a similar size cat on both 8S and 10S. Both work well. 8S will require gas size props in the 65mm range. 10S will run 50-60mm props depending on blade count and pitch. I found low lift Octura X series 3 blades work nicely on Aeromarine cats. Very smooth and efficient with minimal bad handling behaviors. I think my preferred prop was a X457/3. If you have both 8S and 10S batteries, try with 8S first and the 457 prop you have to get a baseline and measure temps. Then try 10S.

Thanks Tyler. I can do 8s or 10s, but will probably prefer 10s. I have an ABC 2414/4 chopper that I could run on 8s, and a few props for 10s. I could start with a X452/3 and move up to an X455/3 or X460, also Prather props up to P250. Will likely run only 10s 1P unless there is and advantage in using the extra battery weight for balance.

[RaceMechaniX]

Peter,
That looks like an Aeromarine sprintcat. I run 2P in mine for weight and for running offshore classes which require a little more capacity depending on the the course layout.
10S1P will work just fine and as you said start with small props and work your way up.

-Tyler

[Peter A]

Peter,
That looks like an Aeromarine sprintcat. I run 2P in mine for weight and for running offshore classes which require a little more capacity depending on the the course layout.
10S1P will work just fine and as you said start with small props and work your way up.

-Tyler

Cool. Do you have/ can share any pics of your setup? This is currently set up with a center mount rudder. Does that work well or am I better going with an offset rudder for ovals? What about prop height? Asking because this is my first tunnel

[koen]

Hi peter a centre mount rudder or sturdder works perfect,irun a sprint cat 36(yours is a sprint cat 42/90)the advantage is it will turn on a dime some say it costs some speed ,but my saw record is 102mph so its ok

[koen]

By the way this boat likes Prather props

[Peter A]

Any idea what is the best CG?

[koen]

Hi Peter i use CG at30% from boat length and you can play whit the CG by using the batterys depending on the wind and waves and the boat likes a chop.When setup is perfect it will be your best boat and you can not believe how this boat will handle

[koen]

It is measured from the rear

[RaceMechaniX]

Here is a view inside mine with the Castle 2028 and a MGM40063.

IMG_0240.jpg

[meangenesracing]

Here is a view inside mine with the Castle 2028 and a MGM40063.

[ATTACH=CONFIG]170310[/ATTACH]

Tyler, what were your speeds with that setup?

[RaceMechaniX]

I think it runs around 65-68 with this motor and a X457/3 prop. It was faster with a 2215 1.5Y and smaller prop but this combo is very safe and reliable. So I can use 20-25C batteries in a 2P set-up for offshore and finish comfortably.
I ran 72-74 I think with the Neu motor and Schulze controller on 10S.
Here is pic of that set-up. One with a 40.160 and the other with a 40.300.

DSCN9473.jpgP1030510.jpg

Video of it running with the Neu motor and a small prop.

[Peter A]

Got it all put back together this weekend. On powering up the motor it was noisy. In removing the end caps the shaft end bearing is shot. I have a couple of new ones so they will go in and I hope to be able to give it a run in a couple of weeks. Our club has 2-lap and 100m records that weekend, all done with laser timing gear. For club records we only run one way as our pond doesn't allow for much room to turn left and run from that end...for now!