Fightercat Daytona tuning and setup, CG, etc. help!

[jetnfast]

Hello all,

I just finished my build. I did a test run this evening on 4s. It seemed really slow, and the prop seemed like it was cavitating based on the rooster tail and what I could visually see and hear. I have the CG at around 9.5-10" from the back of the transom. My strut height is no lower than the sponsons when sitting level. The rest of my build and setup can be seen here:

http://forums.offshoreelectrics.com/...-Daytona-build

The boat seem to get up on plane fine, but WOT was really slow, maybe 25 mph or so. I would expect more out of this boat on 4s. My Spartan on 4s does about 30-35 mph easily. After a few minutes I brought it in and lowered the strut about 1/4'' to 1/2'' and that didn't seem to make much a difference. Could it be the CG? Should I just run it on 6s? I only ran 4s just to test out everything and check for leaks. Other than the speed on 4s and possible cavitation, it seems like a stable boat. Thoughts??

[ozzie-crawl]

1580kv to me seems very low for 4s. mine runs a 2200kv on 4s with a 442 and is in the low 50s.
COG on mine is 30% and strut is just of the table when hull is sitting flat and has very slight prop angled down.

[jetnfast]

Agreed, and that could be all it is...too low a Kv on 4s. I plan on running 6s tomorrow and see what happens....

[jetnfast]

....6s was much better, ran like it should. I think you were right about the Kv to Cell matching, it just wasn't cutting it on 4s. I didn't intend to run it normally on 4s just for the first two runs to get a baseline and test everything else out. It ran like it should on 6s, although I will need some more tuning. I only hit 45 mph, it should do about 55-60 mph on this setup, so I got a lot of work ahead of me!

[ozzie-crawl]

That sounds a lot better. Try strut levell with sponsons sitting flat on table maybe a slight down angle to prop.
30% cog.
Testing new setups can be a bit of a nervous time, for me anyway.
I tested my 37" twin cat a couple days ago. 64mph first run was really happy

[ls1fst98]

now im really worried about my twin on 4s with 1300kv outrunners to cruise around with, mat have to bight the bullet and go straight to 6s.

[jetnfast]

now im really worried about my twin on 4s with 1300kv outrunners to cruise around with, mat have to bight the bullet and go straight to 6s.

Yeah I think 1300 kv is too low for 4s, I would go 6s in parallel for 12s total. That would be a nice match to 1300 kv twins.