10,000

All I can say is this looks like the real deal.
Too bad i don't have 3000 bones to spend.
And there is a bigger one coming appearently.
WWW.Boosthead.com

Rx7carl

Interesting. The limiting thing is the starter motors that power it. Hi torque yes, but series wound DC motors have a very short duty cycles. Thats why it has a 15sec duty cycle, and you better let it cool down b4 you boost again. Neat for specific applications though, like drag racing.

Aaron Cake

iTrader: (1)

This is untrue. Series wound DC motors are built to spec, depending on the duty cycle needed. Many are designed for 100% duty. It is just the cheap starter motors that overheat in a few seconds. Series DC motors are used in everything from electric cars to power drills, many operating continuously.

10,000

Imagine a pair of these things pushing through an intercooler..... hmm.

SCCA racing V8 RX7

I have used old heater blower motors for my water pumps for years and I still have them all running back from 1993. Cheep and very cool.

seanrot

iTrader: (2)

Wow could you imagine, that would be at full boost in what milliseconds. no time to creep up like a beltdrive or a turbo. Just Boom lets goooooo.

Rx7carl

Good point, however looking at the system, it looks like they are using starter motors. No biggie, you just can't be boostin all the time.

10,000

And it flows 405 CFM. This is a match made in heaven for a stockport 12a or what? you could just use a SterlingCarl carb and a WOT switch to activate both the SC and the have the same switch turn on just the fuel portion of a wet Nitrous system with a 75 HP jet in it. that'd be a consistant kick inthe pants 'eh?
If only I had a few grand....

jimmdog

Carl You sound like you know your stuff, I some times Have to drive a car in the shop on the starter motor (HONDA) those things are bullit proof, I've driven them as far as 150 Yards on the key, Don't under estimate a good starter motor. 3gs. and Id have one of those Jobbys

Rx7carl

Oh I dont doubt it jimdog. Just constant duty on a starter will kill it. I use the starter to roll my racecar onto my trailer (which is obviously uphill). They just need a cool down cycle after that. Thats how they are engineered.

atsturbo

Geoff Knight here--Boosthead.com--See you are talking about the ESC--what an awesome product (If I may say so myself)
Yes, those are three starter motors, but they are NOT your average starter :-) They start life as a 2.5 hp motor and are tweaked to 6.5hp each. I have tested these for hundreds of hours, and ONLY if you run the motors for over 30 seconds at 36V+ do they destroy the armature and brushes. As a matter of fact, at SFP on Thurs 12-11 we ran four consecutive pulls on the dyno--with about a minute between them, and after all four runs to 110mph the motors were still warm--not hot. Remember that we are not pushing them at all on the base model with 5-6 psi.
If a 1.5" hole is cut into the brush cover and baseplate adapter, and a small electric fan blows air through the holes (I have done this with simple 1.5" ducting) the motors never get hot. You can ask me for the race motor windings from the beginning and run 48V @ 10hp each motor. That is how you get 20+ PSI flowing 550 CFM which then tapers down to 5 psi. Obviously I dont sell that to someone with three first names, or someone with brothers who all have the same name (Derryl, Deryl, & Deryll!!!)
BTW, check out the runs done on 12-11. They defy all known principles for hp increases under boost. We saw more than 100% increase at certain rpm levels at only 5 psi. That same phenomenon has occured with two other cars, so it is not a fluke. The ' 98 Altima KA24DE 2.4 4-cyl auto trans is a real road slug. It is completely stock except for the ESC.
Running NA we get a high 17 sec car with a vericom, and a low 15 sec run with the ESC on. We are bringing the car to Moroso next weekend to track test it and have Sport Compact do an article on it. They are sponsoring the race, so it is fitting they will have the first crack at the car. I will let them tech inspect it so noone claims NOS hidden somewhere, and let them drive it for the NA and ESC runs. I think that is as fair as it can get. Everyone is invited to come and see it. We may have several cars there if we can get the owners to come.

Directfreak

iTrader: (2)

I just saw your ad in this Month's Turbo. I didn't know you guys were based out of South FL.

It will interesting to see some dyno graphs from Frank's dyno-jet on that E-Charger. Seems like a great idea.

What do you do for fuel?

10,000

Wow Mr. Knight, I wasn't expecting you to be contributing to my thread! We're not worthy...You have made something very cool and iI am confident you will do well with it. Its about time something different came along. Do you plan on making a kit for the rotary? More specifically do you plan on making a kit to blow through a carbed 12a? If you have such an inclination I would like to be the first to wholeheartedly offer my car as a test platform, too bad I don't live in Florida anyway, congrats. on the release.

HeX

Wow! This is fooking cool. Can't imagine what these products will look like in a few years when every car manufacturer has 'em. Next to come, powersteering, A/C, etc,...

atsturbo

We use a simple FMU for fuel control. When running a safe 5-6 psi an FMU is quite consistant, and VERY inexpensive. I give my customers the name of David Shih who sells brand new 12:1 units for $99.95 plus $5 shipping.

We will not be making specific kits for any car. I have several companies who plan on keeping diagrams for the simple mounting brackets they bend so in the future they can make more. The ESC mounts anywhere you want to place it. If you want the weight in the back (like an RX7 would LOVE, mount it in the rear hatch or wherever. A simple 2.5" tube can carry the air to the throttle body, carb hat, or air box. The ESC is completely independant of the engine, so it matters not where you mount it.

I have a Neon ACR that is being built to run low 10's on my ESC. The batteries and ESC will mount where the passenger seat resides now. A 3.5" hole in the firewall with a grommet will allow the 3" pipe to run to the large front mount intercooler and then to the engine. I will be running 26-30 psi at the launch. My ESC motors can be race prepared to make 10-12hp each--30-36hp total. That will give me 25+ psi up to 2500 rpm and then boost will taper in a linear fashion to 12-15 psi at 7000 rpm.

10,000

Hey Geoff, I am assuming that the ESC must be kinda noisy, out of curiosity what might you compare the sound to? I am sort of picturing it sounding like one of those pneumatic diesel bus starter motors....so what might you compare the sound to? By the way I am saving for one of your ESC's sir!

atsturbo

The best description of the sound is a low pitch siren. The rotors spin 10K to 12K rpm, so the rotor whine is audible from 300-500 ft--It is LOUD!!!

Aaron Cake

iTrader: (1)

Still, while starter motors will work, I don't believe they are ideal. Ask anyone who has ever raced a bar stool. Also, years back I made a starter motor based go-kart, and I modified the motors as you described (almost exactly). I had constant problems with overheating. Another issue is efficiency. As anyone who has done any work with electric motors knows, starters are very inefficient.

I also don't believe your 6.5HP rating...Let's call 1HP 700W. It's actually 760W or thereabouts, but 700 is easier to work with...At 12V, that's 58 A per motor. Times three, an you're looking at 174 A..

I'm not saying you're lying, but my calculations just don't add up...We're looking at a lot of battery power to run them (or alternator power?). Of course, if it's a 24V system, we now need 2 more 12V batteries and a way to charge them (weight). And what kind of relay is being used to break 174A? I assume something like the Avcon or Bubba Contactor? Magnetic blowouts will be necessary to prevent arcing, but I'm sure you've already thought of that.

tmiked

Aaron, good reply but 1000 Watts/HP would be closer because the motors are way less than 100% efficient. At 36 Volts thats 180 Amps for 6.5 HP. Possible but not too practical. I guess it is sort of a gadget guys nitrous.

atsturbo

Good and fair questions. I have tested the units at 875 amps @ 24V producing 16.5 hp on a dyno. All dynos have an efficiency loss of at least 10%. The motors run for only 15 seconds max, so the heat buildup is not what you would get in a go-cart. Had you placed a small ducted fan blowing cool air through the armature you would have never seen overheating. To verify my hp claims, go to Magnusonproducts.com, open the specification page for the MP62, and plot the airflow and hp required to turn the SC graph. You will realize I am DEAD ON.
We use FOUR batteries--the Optima batteries are OK, but using only two will ruin the batteries internal connection. I have fried three of the red-top units. I now only use and recommend the Odyssey 680 model battery--and four or six are required.
I use Five 175 amp relay/solenoids. Two connecting the two sets of batteries, and three carrying power to the ESC. They are silver contact severe duty units that all EV guys are familiar with. $15 each.
The starter motors have 48V composition brushes used which work a little better when warm. 12V compositions are softer and prone to premature wear. I had the motors lab tested, and the expected life is 1000hrs at 15-20 sec intervals. That is 24-30 YEARS. 15-20 second runs being run 15-20 times per day. 250-350 sec per day. 4-6 minutes a day MAX. 10,000 minutes. Then the armature can be turned and a new set of brushes replaced for less than $100 total.
The Eaton averages 150K miles when belt driven. At 300 seconds per day it translates to 4 million miles.
My unit in the Altima has been abused, tested, run 48-60 volts into it, burned up three sets of motors during testing several years ago, and that same unit has been on three cars over the last two years. When I tear it down for inspection every other month, I put everything back on it as there is NO wear to it AT ALL. I average 5-20 runs per DAY. And my runs are one after the other after the other till the batteries go down. I recharge them with my 200 amp shop charger in a few minutes, and go do it again.
Look at what the starter normally has to do--it has to get several hundred ft/lb to develop immediately to get the heavy engine with compression that is cold and does NOT want to turn turning 200-300 rpm so it can start. And sometimes the car wont start so you try and try again and the battery goes dead. So you do this dozens of times yet the starter lasts 10 years. That is ONE starter. I use THREE. What do they have to do? Get two 3.5" rotors turning with two other motors helping. I run a good gear ratio so they dont come anywhere near stall speed which is where heat is created.
Please keep asking good questions--I truly appreciate them. I put the questions and answers in my FAQ files.

10,000

Have you used one on a rotary engine yet at this point?

honegod

how about a little bypass from the pressure side to the motors that opens immediatly AFTER you tell it to stop producing boost, have the motors run for another couple seconds at low pressure just blowing a jet of cooling air through the motor assembly to suck a chunk of heat from them.

how much do all those batteries weigh ?

would a hefty cap bank help with the starting surge draw ?

Nick-7

I think the system is a good idea, but I would like to know how much it weighs total (everything that had to be put on the car to allow it to run, batteries, esc unit, ducting, everything).

tmiked

4 batteries, contactors, big electric motor, supercharger all for 15 seconds of boost..... No way. N2O is much more practical for the same effect.

Tofuball

"What about the extra weight?

The ESC design uses four 13lb batteries (the small Hawker/Oddysey 680 models) to power it, so you gain a total of 42lb for the ESC-400 and 52lb from the batteries. The typical turbo kit weighs 90lb, and the typical SC weighs 70. So the 'extra weight' that people refer to is not much more than any aftermarket system. You can use an Oddysey in place of your regular 38lb car battery which saves 23lb. That makes the system lighter than most complete turbo kits. "

--- From the FAQ