More Speed questions

[roadrashracing]

I have hit 31 mph but am looking for just a little bit more, I am running 25c 4000 2 s packs, stock motor, the blue speed control, and a 52x55 grim prop. I messed around with the strut angle and feel thats its in the ball pack. Does a higher c rating or esc change give you more speed? Just really learning boat setup now.

[Make-a-Wake]

What kind of boat is this??????? Higher C rating has more punch to it and they will come in cooler.

[roadrashracing]

An impulse since it was listed under the impulse area

[Make-a-Wake]

My bad, i just looked under the "new post" category, been using it as it saves time showing only new posts. Those sure are neat boats...........what are your temps now at the 31 mph mark? If fairly low you can prop up, however you are using a large one now, hmmmm 52x55, right?...........an ESC change wont give you any more speed. The only way a new speedo would help is if you go to a bigger motor and need one.

[Make-a-Wake]

Didnt think they made a 52x55...........thats awfully large...............

[roadrashracing]

my bad prop is 42x 55 elctronics are cool battereis are warm after run.

[roadrashracing]

so a higher c rating might give you a mph or 2, new batteries are coming in spring

[Darin Jordan]

so a higher c rating might give you a mph or 2, new batteries are coming in spring

When you get good cells... Try an Octura X645... There are several prop options that will get you closer to 40, but I hate to recommend them unless people are willing to upgrade all their connectors, and also are willing to push their equipment over it's "rated" limits...

If you upgrade all your connectors to 5.5mm minimum (you CAN live with the deans, though they will get warm), you can push some pretty decent props behind this boat with the stock power system. The X645 is a really good starting point.

[roadrashracing]

Not looking to haul ass all the time just for a fast run here and there, I am running traxxas connectors and 4 mm motor connectors. I mean just these lipos where a big jump for me.

[Darin Jordan]

Not looking to haul ass all the time just for a fast run here and there, I am running traxxas connectors and 4 mm motor connectors. I mean just these lipos where a big jump for me.

An Octura X645 will give you some good, fun speeds... The 42x55 is a little small in diameter, though it can be made to work as well if you know where to bend on it to increase it's pitch... And ABC 45x55 is also a good choice...

[roadrashracing]

Well I was impressed with 42x55 prop change

[Make-a-Wake]

Consider an m445.....................

[Darin Jordan]

Well I was impressed with 42x55 prop change

Despite what the prop-charts say for pitch, the 42x55 is a GOOD prop... It's rated at 55mm, or 2.165" pitch... I've NEVER measured one that is that low, however... most are over 3"! The stock prop, essentially a Prather 215, is 2.5"...

Hope you are enjoying the Impulse!

[Darin Jordan]

Consider an m445.....................

The M445 is actually LESS pitch than the stock prop (2.478"), though the blade area and shape may add to the speeds...

[roadrashracing]

Will setup the boat different ways make a big difference in speed? I only have one set of lipos so everytime a switch battereis I need to mess with the setup.

[Make-a-Wake]

Here' my 10 cents on the boat ride/attitude.....................calm waters need to be back in the 28-32% cog range..............a little further up for rougher water.

Here's an example of my very similar boat........32" Pursuit in calm water..........i like this kinda ride, up top on the pad. Higher 40's on 4s and hit 59 on 5s for a quick test run.

..

[roadrashracing]

ran on 5s today, hit 40 mph, first time driving a fast boat and it was great!

[de-pro]

never had good experience with the stock electronics although the same gear kicks a$$ in my sv27 with a 42x55 prop. Go figure.
changed the motor to a leopard 4074 2200kv and esc to seaking 180. running with m447 prop on 4s1p 5000 40c batteries. temps are all below 100. remind you the temps here are pretty cool now.

Mfmdx.jpg

[G1ST]

de-pro
What do you think you are getting for speed with the M447?
Greg

[de-pro]

I didnt have a GPS but my guess would be high 40s to low 50s. I have a GPS now however everything is packed away for winter
Here is a little video, water was a bit rough so I couldnt get the full speed for long

de-pro
What do you think you are getting for speed with the M447?
Greg

[roadrashracing]

Time to take this thing out of winter storage.

[dana]

try an x442. its 42mmX58mm pitch, little more than your 42/55 grim.

[Stephavee]

38.3mph with S/B M545
36.5mph with S/B M445
speeds on Etrexs gps



http://youtu.be/PiEfcBNedSQ