Spec Electric Tunnel Racing

[lohring]

The Memorial Day District 8 race featured some electric classes for the first time. The popular P Spec Motor (and speed control) electric tunnels were especially fun. Jerry Dunlap captured an exciting sequence where Brian Buaas passed me at the last buoy for the win. These boats are the equal of 3.5 nitro tunnels in performance, but at lower cost. See http://www.intlwaters.com/index.php?autoco...m&album=515

Lohring Miller

 

[AlanN]

This class is offered at the Canadian FE Nats being held this weekend. The tunnels will run on Friday. If there are any tunnel heads out there stop on by and check it out. The race will be held in London, ON.

 

[racer504]

The Memorial Day District 8 race featured some electric classes for the first time. The popular P Spec Motor (and speed control) electric tunnels were especially fun. Jerry Dunlap captured an exciting sequence where Brian Buaas passed me at the last buoy for the win. These boats are the equal of 3.5 nitro tunnels in performance, but at lower cost. See http://www.intlwaters.com/index.php?autoco...m&album=515
Lohring Miller

I'm pretty much clueless when it comes to FE but this does sound interesting. So what is the P Spec engine and speed control? Where can you get them? Do you have any specific rules for this class? Thanks, Mike

 

[Kris Flynn]

Pretty sure the Motor and controller are a SuperVee Setup available from Offshoreelectrics.com and probably anything else goes as far as the rest of the boat (under 34" in length)

 

[raptor347]

Pretty sure the Motor and controller are a SuperVee Setup available from Offshoreelectrics.com and probably anything else goes as far as the rest of the boat (under 34" in length)

That pretty much covers it, SV27 motor and ESC (or Proboat Blackjack motor/esc). 4S LiPos, lower unit of your choice and any opc tunnel under 34".

I'm working on a rule set that will be inclusive of the 12nimh/4S Lipo RTR power systems. Both the Aquacraft and Proboat brushless systems will be options. There will also be some technical specs for the motors.

This is not intended to be an official national rule set, just fun racing.

 

[Kris Flynn]

Hey Brian,

This 'just for fun' racing seems to be sparking some much needed interest in FE Outboards, which is great!

Kris

 

[Marty Slater]

Please keep the info coming

what kind of price for the SV27,esc or the Proboat Blackjack motor/esc

an the 4s lipo pack or do you need 2 packs

speed an run time are you getting

is this the wave of the future? will still have my nitro also

Marty

 

[Ed.R]

Hey Brian,
This 'just for fun' racing seems to be sparking some much needed interest in FE Outboards, which is great!

Kris

Once again I'm confused , I thought all TOY boat racing was supposed to be FUN !

Love this idea though , might have to sell a sport 40 hydro to make some FE tunnels .

What props are people using ? How about motor height and other set-up stuff?

Ed

 

[Darin Jordan]

Please keep the info coming what kind of price for the SV27,esc or the Proboat Blackjack motor/esc

an the 4s lipo pack or do you need 2 packs

speed an run time are you getting

is this the wave of the future? will still have my nitro also

Marty

Marty... Let me see if I can answer your questions...

Motors:

You can get the SV27 or the BJ26 power system from www.offshoreelectrics.com (OSE), or Tower Hobbies. Steven at OSE is one of the BEST supporters out there for FE RC boats, so I like to give him as much of my business as I can... If he has the parts, I buy from him. Doesn't hurt that he usually has the best prices as well!

The SV27 setup is less expensive, but not quite the quality of the BJ26 as far as the wires are concerned. Both perform about the same... and hold up equally well. I think (my opinion) that the wire quality issue makes the BJ26 setup easier to solder connectors to.

For the SV27 setup, just use the stock ESC for it... It holds up just fine, is basically water-proof, and is again, CHEAP to purchase... The entire power system from OSE is listed at $139.99...

The BlackJack 26 (BJ26) motor is a bit more... I think it's basically a HiMax 3630-1500 motor. It comes with the water jacket and is listed at $79.99 from OSE. The ESC for this motor is listed at $69.99 at OSE... The SV27 ESC is $59.99. The BJ26 ESC can also be programmed with a separate programming module...

I've run the BJ26 motor in my SV27 with no other changes (stock SV27 ESC, etc.) without problems... and it performs in Spec SV27 trim right on par with the SV27 setup... In heat races, one wouldn't be able to see the difference in performance, as they are VERY close... I've been told, however, that people have burned up SV27 ESCs running the BJ26 motors, so it might be worth it to pay the extra $$$ to get the package (Motor AND ESC)...

Batteries:

We run Stock 3.5 sized hulls... TS-2s, WoodStuff 28s, LeeCrafts, etc... all in the 26-30" range. There is really only room for 4S1P, but that's just fine, because that's all you need... We usually use at least 4000mah cells... I choose to use 4500s or 5300s, just for the extra buffer and sometimes, the weight helps as well. So, you'll just need ONE pack of 4S1P Lipos... which you can get from www.cheapbatterypacks.com for a reasonable price. I, and several others in our club, use the Elite brand, which currently come in 30C ratings and are the very best BANG for the BUCK!

Speeds and Runtime:

We are able to easily complete 1-mile race distances with our setups. We don't do a full mill, but we could, and we do often run a cooldown lap. Much further than this would be possible, but not advised without larger cells.

Speeds are easily into the lower 40s with a basic setup. My WoodStuff 28 has GPS'd at 44mph... and Brian Buaas is able to go a bit faster with his TS-3 (HURRY UP AquaCraft and get this RELEASED!!) This is with the SPEC setup... The same TS-3 went WAY into the 50s with a more aggressive motor setup...

As for the future, I'm not sure if this is the "wave", but I DO think that the future for FE tunnels is looking bright... We can't discount the impact that AquaCraft offering the TS-2, and now the VS-1, has and will have on this future. The TS-2 got us started for a VERY REASONABLE price, and now the VS-1 will up the ante' considerably by offering a really good raceboat. If the TS-3 gets released, it will provide an excellent platform for a more "open" motored platform, so we'll have the bases covered.

Hope this helps! Now... go build one and let's RACE!!

 

[Bill Oxidean]

Whole thing sounds Awesome, we could use more electric tunnel racing..

BBY offers a tunnel as well called "Hooters" sounds like a fun winter project..

 

[lohring]

My boat is a Leecraft XTR-21 with the Blackjack motor and speed control. During testing I ran a little too large prop and pulled 80+ amps (according to my Eagle Tree data logger) through this 45 amp speed control for about 6 laps on a 1/6 mile course. My understanding is that the Aquacraft speed control is equally tough. These spec motors are a great way to power a large range of electric boats. Someone needs to write rules for a P spec motor class.

Lohring Miller

 

[Ed.R]

Has anyone tested , back to back , 4s lipo vs 12 cell Nimh packs ?

How long does it take to charge a 4s lipo ?

Ed

 

[jayt]

Has anyone tested , back to back , 4s lipo vs 12 cell Nimh packs ?

Yes, depending on the setup I saw increases from 4-8 mph on oval boats. But this really depends on the quality of your NiMh and LiPos. Cheap NiMh vs top end LiPos and the difference could be greater. Good NiMH vs cheap LiPos, expect less.

How long does it take to charge a 4s lipo ?

This depends on the charger and the level of discharge, but it usually takes me around 45 minutes.

.

 

[Darin Jordan]

Has anyone tested , back to back , 4s lipo vs 12 cell Nimh packs ? How long does it take to charge a 4s lipo ?

Ed

It's been my exerience that there is really no comparison... a 12-cell pack has a nominal voltage of 14.4V (1.2v/cell) and under load MIGHT hold around 14V or so for the first 30-seconds or so of the discharge. I emphasize MIGHT... more likely it would be drawn down, under load, to a little over a Volt/cell, or around 12-13V total, and the cells will only last for 1/2 season or so before they start drastically falling off...

A 4S Lipo pack, on the other hand, has a Nominal voltage of 14.8V (that's 4-cells * 3.7V/cell) and would charge up to 16.8V (that's 4-cells * 4.2V/cell charged), and would hold at least 3.7-4.0V/cell under these loads for most of the race... that's 14.8-16.0V under load, and you can expect that kind of voltage for the majority of the race... AND, the cells will last for at LEAST a full season, and in my experience, Two or more seasons, at those loads and with the proper care between races...

Couple that with the fact that Lipos are 1/2 the weight, and the performance is simply better all the way around, in my experience. Also WAY easier to deal with at the races, and between race weekends... No peaking to worry about... etc...

As for charging... about 45-minutes for the typical pack... but I only charge at 1C, and good packs are capable of being charged at 2C, so it could be faster, but generally, there isn't a need to use that capacity... I prefer to have a couple of packs anyhow, so getting charged isn't usually an issue...

 

[raptor347]

Has anyone tested , back to back , 4s lipo vs 12 cell Nimh packs ? How long does it take to charge a 4s lipo ?

Ed

Ed,

NiMH's don't stand a chance. With a descent charger, you can recharge in less than an hour. You can run the LiPo's as many times in a day as you want, no need for extra packs.

The setup on my TS3 is:

SV27 power sysem

4S1P Elite 5300's

REK lower unit and motor block

M445 prop (other options I know work: 42x55, 45x55, M545)

Prop shaft is parallel to the ride surface. The bottom of the shft is 3/16" above the ride surface. The prop shafts run a bit higher than a nitro tunnel because of prop size.

The boat was running 20 second laps at the race last weekend. Roughly on par with the "average" 20 stock boat.

Hope that helps.

 

[AlanN]

I highly suggest using either 20 or25C rated cells for the low amp draw setup of an SV of B/J motor combo. The 30C cells are higher internal resistance cells meant for seriously hard amp draw. No need to waste the cash for something you don't need.

I run the same motor and prop combos as Brian with 20 or 25C rated 5000mah packs. 4S1P.

To be practical for racing 2 packs would be warrented. Since the nitro/gas guys are used to running heats quickly during a race you may have some extra pit management keeping one pack charged in time for the next heat.

And as far as longevityof lipos goes....I have been using some packs for 2yrs now without signs of fading. These have been used in low amp draw setups as described above.

Also, I have ran a couple of races against nitro with my tunnel and the reliablity of F/E far exceeds that of nitro. No need for air pressure readings and such.

 

[Ed.R]

Thanks for the info ........ This is a great way to help the FE tunnel classes grow .

What type of care is needed on a Lipo pack ? Do you need to fully discharge it after your done until the next race ?

Can Lipos get a memory ?

Seems to me this class would be the best for new comers to get started in . no worry about getting an optimal needle and paying $30 or more dollars for a gallon of fuel .

Ed

 

[Darin Jordan]

What type of care is needed on a Lipo pack ? Do you need to fully discharge it after your done until the next race ?Can Lipos get a memory ?

Ed,

I charge my packs the night before the race... or maybe the morning of... I race... pull the packs and put them on the charger... charge them up... go race again... repeat this cycle for each heat...

At the end of the day, I make sure they are dry... put them back in my battery box... and repeat all of this again for the next race weekend...

Lipos don't get a memory... other than the one you'll take away from the race of having SOOOOO much FUN!!

I find it's also very useful to have a means of identifying packs that are fully charged, and religously sticking to this process. The worst failures of Lipos I've seen are when people run packs down too far.... usually because they forgot which packs were charged and which weren't... My method is simple... When the packs are charged... I put a Post-It flag on it... When I pull them from the boat, the flag comes off until the pack is charged again... As long as I'm diciplined about this process, it hasn't failed me yet...

 

[DJ Campbell]

Has anyone tested , back to back , 4s lipo vs 12 cell Nimh packs ? How long does it take to charge a 4s lipo ?

Ed

Ed,

NiMH's don't stand a chance. With a descent charger, you can recharge in less than an hour. You can run the LiPo's as many times in a day as you want, no need for extra packs.

The setup on my TS3 is:

SV27 power sysem

4S1P Elite 5300's

REK lower unit and motor block

M445 prop (other options I know work: 42x55, 45x55, M545)

Prop shaft is parallel to the ride surface. The bottom of the shft is 3/16" above the ride surface. The prop shafts run a bit higher than a nitro tunnel because of prop size.

The boat was running 20 second laps at the race last weekend. Roughly on par with the "average" 20 stock boat.

Hope that helps.

We ran a couple of Tunnels with SV27 and 4s lipo setup at out local Minnesota race. Wish ther more than 2 of us, we had a blast with em! I ran a DPI against a H&M. We were pretty even.