ESC rules in IMPBA/NAMBA

[Bill Britton]

To answer my question is it corret to say:

IMPBA you can use any ESC?

NAMBA you have to use a PB/AQ ESC?

I only have one thing to say I belive we as racers should be able to use any ESC if you burn it up, live and learn. Nitro motors are not no brainers.

Not everybody wants to buy the AQ combo for $160 when you can spend $110 to do the same thing!

Just my .02cents

Tim

Nope. The other way around.

Namba = any esc

Impba = Check your district first before you buy. Also check any districts you will be racing in.

 

[lohring]

I, along with several others in my club started running the P spec classes (hydro and tunnel) with the UL=1 ESC. I also ran the Proboat ESC in my tunnel. As different things got hot when we ran props with more pitch, we changed them. The stock connectors got replaced with 5.5 mm bullets when the solder melted on the stock connectors. The speed controls were next for some of us. Last Sunday I raced with three very similar Raptor riggers. The big difference was the ESC. All boats were quite reliable and the components were not getting too hot. Because the boats with Castle or Turnigy speed controls could run props with more pitch like an S-15, they were 5+ mph faster. The boats with UL-1 ESCs ran props like an H-10. All the props were modified to give close to the best performance possible with reliability. Over the past three race seasons we have increased the speed of these boats at least 5 mph. See http://www.intlwaters.com/index.php?showtopic=47065 where Eric Bourlet talks about his 1:23 NAMBA heat record speed.

Finding a prop with not too much current draw has been the key. If you require stock connectors and ESCs, that prop will have less pitch than ones run with bullet connectors. This might be the best case of all because the soldered joints will usually come apart before anything else fails. The next step up in props and speed comes from replacing the ESC. At this point, we have boats most people consider fast with components that aren't too expensive. This same weekend a racer had his new, very fast 3.5 CMB rigger engine lose the connecting rod main bearing. This destroyed the rod, piston, and sleeve. That was a lot more expensive than melting a P spec motor.

Lohring Miller

 

[D. Newland]

Thanks for posting Eric's link, Lohring. I actually forgot an important piece of information in my post. Grim's 1:24 heat time at the '09 Gas Nats (FE ran a few classes) was done w/a UL-1 ESC.

 

[lohring]

I still say, and that proves, it's all in the prop no matter what ESC you use. I originally felt NAMBA should have limited the ESC as well as the motor. Now I don't think it mattered.

Lohring Miller

 

[Doug Smock]

The difference between the AquaCraft ESC and an aftermarket ESC in a P spec hydro is at least 5 mph. It is about the same in a tunnel. The aftermarket units have lower internal resistance as well as higher current capacity. This lets you run more prop and the motor becomes the weak link. The cost doesn't need to be higher, but it means that a new racer can't take his UL-1 components and build a boat.

Thanks for posting Eric's link, Lohring. I actually forgot an important piece of information in my post. Grim's 1:24 heat time at the '09 Gas Nats (FE ran a few classes) was done w/a UL-1 ESC.

I still say, and that proves, it's all in the prop no matter what ESC you use. I originally felt NAMBA should have limited the ESC as well as the motor. Now I don't think it mattered.

Lohring Miller

 

[photohoward1]

The difference between the AquaCraft ESC and an aftermarket ESC in a P spec hydro is at least 5 mph. It is about the same in a tunnel. The aftermarket units have lower internal resistance as well as higher current capacity. This lets you run more prop and the motor becomes the weak link. The cost doesn't need to be higher, but it means that a new racer can't take his UL-1 components and build a boat.

Lohring Miller

No way....I have run all the ESC controllers and see no noticeable speed difference. It's all in the set-up. I do change all my connecters to 6mm at the Motor and 5.5mm at the Batts. The smaller stock connecters are the week point.

All said and done though I do not run the stock ESC because 45amp or 60amps is not enough. The Turnigy 120 is a better cushion.

HT

 

[Kris Flynn]

Howard, doesnt your last line go against the rest of your post.

If you run a 120 amp speedy because 60amps is not enough, then you must be faster with the 120?

 

[Don Ferrette]

Howard, doesnt your last line go against the rest of your post.

If you run a 120 amp speedy because 60amps is not enough, then you must be faster with the 120?

DING!! DING!! DING!! Give that man a cigar. B)

The part I find most amusing in all of this is it's not like we're talking nitro with leaner needles, higher nitro % or all the other IC type "variables" rather this involves simple math-

volts x amps = watts = horsepower

The voltage is the same but your pulling more watts ......

 

[Doug Smock]

Howard, doesnt your last line go against the rest of your post.

If you run a 120 amp speedy because 60amps is not enough, then you must be faster with the 120?

DING!! DING!! DING!! Give that man a cigar. B)

The part I find most amusing in all of this is it's not like we're talking nitro with leaner needles, higher nitro % or all the other IC type "variables" rather this involves simple math-

volts x amps = watts = horsepower

The voltage is the same but your pulling more watts ......

Don, Kris, try to keep up.

The additional power ( loads above approx. 63 amps where our testing shows the effeciency of these little motors goes in the toilet, your results may vary depending on the device(s) used for testing ) doesn't go to speed or heat, even though "the motor is the fuse". It just vanishes. :blink:

This is known in some circles as Hmmm's Law.

There is no clear definition of Hmmm's Law, so we'll just have to accept the fact that there are some things we may never understand.

Just having a last little bit of fun with this. B)

Thanks fellas!

See ya at the pond!

Doug

 

[Don Ferrette]

Hmmm's Law ...... laughing so hard it hurts. :lol: :lol: :lol: :lol: :lol:

 

[photohoward1]

Howard, doesnt your last line go against the rest of your post.

If you run a 120 amp speedy because 60amps is not enough, then you must be faster with the 120?

Not really. The Turnigy speed controllers are cheaper though.

I think mike ball runs stock stuff and his stuff flies.

 

[Dick Loeb]

Thank GOD for the HUMMMMMMMMM LAW :wacko: :wacko: :wacko: :lol: :lol: . Way to go DOUG we've been SMOCK SMACKED again !!!

 

[HTV Boats]

As it now stands? Namba any controller is fine. IMPBA rules no restrictions. IMPBA Dist 12-13 local rules AQ controller only? Proboat? So if you race outside those districts your probably good to go with correct motor.

One question on speed relying on amps? You can load any esc to amp up with too much prop. So if you put a say X450 on a Dist 12-13 legal AQ P tunnel which is going to consistently fail first , the motor or controller?

Mic

 

[Doug Smock]

Good question Mic. I don't have the answer as I have not seen either fail in D13.

My guess is it could be either /or, or both. Much like just about any combo.

Perhaps Sailr can help us out here.

The Limited / Spec. classes don't officially exist in the IMPBA.

Doug

 

[Chilli]

If you slightly over prop, IMO the motor will give out first. This was the case for my Limited Sport Hydro. The UL1 motor was coming back after a heat in the upper 140's with a wisp of a odorless white smoke when I pulled the cowl. I didnt change the the set up just to see how long the motor would last.It ran about 15 heats before the motor finally died. A guy in my club blew a UL1 controller and in his case he was way overproped. Four laps and POOF!

I'm not going to get in the speed controller debate untill the IMPBA decides the time is right for a National Limited/Spec Class. I'm just going to follow the rules in the areas I'm racing in and have fun.

 

[SeanKewley]

. I'm just going to follow the rules in the areas I'm racing in and have fun.

^ What he said

 

[Doug Smock]

I'm just going to follow the rules in the areas I'm racing in and have fun.

 

[T.S.Davis]

Holy crap. 3 or 4 seasons of spec racing and we're still talking about speed controllers.

I've burnt, baked, or lightly seared every kind of speedo and all of the spec motors available. Baked a Hydra 240 in spec rigger but the UL motor was fine. S15 pitched a ton. Hmmms law.

At the 10 NATS I was up to a detongued X450 in sport hydro on a whip with a stock AQ setup. It was too much. Just made for a hot motor. I suppose you could say my extra watts/horsepower were just going into the air. Took it back to MI, put a sane prop on, and finished the season with it.

t

MMEU's racers are as fast as just about anybody. Our spec sport and spec offshore classes were both won by AQ combos. In fact, SV27's finished 1-2 in offshore after a whole summer of racing. They ran UL1 motors with 60 amp AQ speedos on 4s1p. Even if guys were faster the water was the great equalizer in that class. We'll see this year.

Until I see some domination by aftermarket speedos I'm not buying it.

 

[Doug Smock]

So 60 amp AC ESCs ARE plenty -O- ESC for UL-1 motors in the Limited classes.

We are back to just a cost thing?

Doug

:wacko:

 

[Chilli]

I LOVE LAMB CHOP!! :wub: