We make it ICE COLD for the 1000HP RX-7.
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  • Mark Keller
    Mark Keller

    After binge watching 3 and 4 rotor builds, thank you! In this video on cooling, forwarding a link on slope control temp with pwm. maybe can provide some alternatives for searching a solution, if it cannot mate to your system. www.google.com/search?q=slope+control+temperature+controller+with+pwm+fans&sxsrf=ALeKk012iwtIH_cUVe_V_n9Jm7Cm6HWeLQ%3A1627176224935&ei=IL38YODCOJTB-wSRz7PoBA&oq=slope+control+temperature+controller+with+pwm+fans&gs_lcp=Cgdnd3Mtd2l6EAMyCAghEBYQHRAeOgcIIxCwAxAnOgcIABBHELADOgQIIxAnSgQIQRgAUMQpWOdgYKNjaAFwAngAgAFwiAHDB5IBBDExLjGYAQCgAQGqAQdnd3Mtd2l6yAEJwAEB&sclient=gws-wiz&ved=0ahUKEwjg0v7mh_3xAhWU4J4KHZHnDE0Q4dUDCA8&uact=5

  • Fredy Luque
    Fredy Luque

    you’re so different and i meant it in the most respectable way possible 🏁🙏🏽

  • Aleks B
    Aleks B

    Fill it with hot glue

  • Ng Garage
    Ng Garage

    I got the same Fans - for my 1jz Scion frs Swap - not going to lie the electrical hardware its total shit lol - im just going to wire it to my Standalone ECU .

  • Ryan Jackson
    Ryan Jackson

    Does anyone know what water pump that is?

  • Keith McNeil
    Keith McNeil

    Love watching your show your work is astronomical and your coworkers but if we could I have young children that watch with me and if you could clean up the language it would be very much appreciated thank you lots of luck in your new endeavors be safe God bless.

  • young11984

    This is why i only use Delta PAG brushless fans, controller and Davies Craig remote pumps. Buy once cry once but have a reliable cooling package

  • yyyyyy

    Your not wiretuck like a pengepul mobil and tubular at enggine managent like a clean. 🥰

  • David Franklin
    David Franklin

    To deal with shock to the system you can do what the car audio guys do nowadays and get a small specialized lithium battery.

  • Slish Cam
    Slish Cam

    The smiling disease archaeologically subtract because lawyer intriguingly breathe towards a guarded sphere. graceful, breezy mind

  • OvAeons

    Hi, I'm Rob Dahm. You would not believe what a tea kettle could do for your performance.

  • Fujiwara Emiko
    Fujiwara Emiko

    0:06 i knew that he is the kind of guy that prefers to play his racing games in hood cam😆


    Half second after Rob asks his coolant question, brain screams cavitation lol.

  • Myles Lange
    Myles Lange

    Those automatic circuit are some of the best circuit breaks on the market. I use them all the time and I have never had one problem with them before

  • TireShredder

    The temp sensor needs to be on the cold side. Any other way is terrible...

  • Brent Chuck
    Brent Chuck

    I dont recommend running those PWM Controllers with SPAL brushed fans. The PWM controller is super low switching frequency, (That's why it squeaks/squeals.) ~500 Hz. The SPAL motors have 20 commutations per revolution. If the fan is spinning 3000 RPM that's 50 RPM/second. 50 RPM/sec * 20 commutations per revolution = 1000 hz ABSOLUTE MINIMUM frequency. So if your controller is 500 Hz. you are essentially only powering half the windings at full speed, and you're going to burn up those motors. (That's not exactly how it works, but for this forum it's a easy way to imagine what's happening.) Low frequency PWM "hammers" motors like that to destruction. TLDR it's going to kill those motors. The PWM controller uses a MOSFET to switch the main load of the fan. At full speed, ~30 amps. So that little electrical component gets f*cking hot. Guess what happens when electrical components get hot? They stop working. So this controller should be mounted somewhere cool, not on a hot radiator. TLDR the controller uses a temperature sensitive thermal component, and it's mounted on a hot radiator. So the controller may not function very long. Bottom line: Brushless fans are the ticket. But I'm a little biased.

    • Brent Chuck
      Brent Chuck

      @Rob Dahm That's was me buddy 😉 I work at SPAL. That's why I'm jaded about the brushless I know what they can do. The C6 Corvette had a PWM brushed fan combo, you can Google how well that worked out for them.

    • Rob Dahm
      Rob Dahm

      You worded it way better than me. I assumed poorly that a thing advertised as pwm would naturally be brushless. My mistake. I talked to spal engineers at length about the proper solution

    • Brent Chuck
      Brent Chuck

      If the switching frequency of the controller was higher, above ~16,500 Hz. It would make less audible noise to humans and be quieter. But the faster you switch the heavy current load of the fan, the more heat the MOSFET has to dissipate. So high frequency controllers are more expensive. Another concern is 'what does the system do if the fans "soft start" too weak and stall?' Does the PWM controller recognize a low power stalled fan? 🤔 Or is that thermal/self-resetting circuit breaker supposed protect that whole system? 🤔

  • Jim Brust
    Jim Brust

    Be careful with getting the flow rate too high. It takes time to transfer the heat to the cooling fluid within the engine and time again to transfer heat from the fluid to the air in the radiator. How about trying a radiator located behind the drivers seat and move the hot air out to the low pressure area behind the rear end of the car?

  • EliteSniperTV

    Man I hate when my air cavitates no good

  • Slumped 2X
    Slumped 2X

    I've learned more from watching Rob Dahm then i did in all my 11 almost 12 years of school🤯.

  • Diaman D
    Diaman D

    fake news channel, buh.

  • Joe Lee
    Joe Lee

    LOL I love Isaiah and Rob. Such chemistry and brotherly interactions.

  • Joe Lee
    Joe Lee

    It's so late at night Isaiah can't stop trying to inhale off the water pump like it's a bong....

  • Joe Lee
    Joe Lee

    "We will figure it out. We always do." - Isaiah Hell yes you do lads. You always deliver.

  • Tony Fc3c
    Tony Fc3c

    Love how we get alllllllll the deatails !!! I'm on the edge of my seat everytime.. thank you 🙏🏼

  • casemodder89

    This is most likely the Pierburg CWA 400 pump for BMW. If you need a good PWM controller for it with LOADS of configurations and functions i like to recommend the tinyCWA by company called tecomotive.com located in GER. Btw. Usually pumps should be installed at the lowest point in the cooling system. So it naturally gets rid of trapped bubbles and is self priming. You both should really change it accordingly. The CWA pump is highly water resistant and robust. So there are no concerns about having it hanging low behind the radiator. Having a pump sitting on top of the engine might lead to a collapsing flow of coolant IF the level dropped by a few inches without the pump running at high enough rpm. Once it pulls air the flow will completely stall. Just an advice - dont ask me how i know...

  • Aj Scott
    Aj Scott

    Fuel Tech for your rx7

  • Darcy skips Ltd
    Darcy skips Ltd

    Should of brought the tiny cwa controller works flawlessly with that pump and half the price and controls for delay Shut down to keep car cooler after a run

  • Kevin Can Fly!
    Kevin Can Fly!

    Rob, what would happen if you ran the car on methanol and not E85? SCIENCE...🤭

  • MaxeMouse

    Robs review of cooling. Digested. "All parts work, probably. Most parts are garbage, certainly. Terrifying information provided, insufficient. Fans move air. Stay tuned!" It's perfect. THX for nerding out!

  • клим мухин
    клим мухин

    Everything is as usual - he piled up a bunch of shiny crap, and as a result, nothing works and does not go anywhere! Everyone sprinkles on drag races ....)))

  • Regan Powell
    Regan Powell

    How do you plan on expelling the air out from above the bottom of the outlet pipe for the radiator?

  • Clubmen Jim
    Clubmen Jim


  • Evan Green
    Evan Green

    Should’ve click baited “twin turbo 3 rotor” 😂

  • phill

    Will you Collab with the Vargas brothers on any of your builds ?

  • Austen R
    Austen R

    Oh hey, the car that rob is gunna drop the 6 rotor in

  • Wasted Time
    Wasted Time

    I’m over hear still not understanding how we getting a video everyday of the month and this the third day without a vid🤔

    • Username

      @BFE 08 WRXSTI he finally fucking uploaded.

    • BFE 08 WRXSTI
      BFE 08 WRXSTI

      @Username You dont need to subscribe when you've got family

    • Username

      @BFE 08 WRXSTI rob never should’ve said he’d upload videos everyday if he couldn’t follow through. This type of shit is why I unsubscribed a few years ago

    • BFE 08 WRXSTI
      BFE 08 WRXSTI

      You don't need daily vids when you've got family 😂😂

  • Simply Nick
    Simply Nick

    Been recommending you to every car guy I run into over here on the West Coast. Gotta rep the fellow MI boys!!

  • Well Built
    Well Built

    “Nothing stronger than… family “😂

  • Burnt Chicken Nugget
    Burnt Chicken Nugget

    Install a potentiometer before you wire the fans into the system

  • Brian Gochnauer
    Brian Gochnauer

    The "old archaic fuse" is a resettable breaker not a fuse; it is a safety thing; if it trips it will reset and attempt to keep the fan running; which is why installation docs said "Don't use a fulse" This type of system is also used on trailer brakes too; to keep from losing trailer brakes because of a loose wire.. As far as your judgement of the shorting issues; at 12 volts it is low voltage; shorting would come from poor wiring practices not the number of amps; amps doesn't make it more susceptible to shorting; unless you're pushing more amps than designed for a wire size and melting it. Those resettable breakers have been around longer than you've been alive; and still in use. Your understanding of how things work is just as shitty as your review of things you don't comprehend. Read up on PWM motor control and design before jumping across a circuit you don't really understand.

  • Cameron Skelton
    Cameron Skelton

    You hitting the gym my guy?

  • Sloppy Mechanics
    Sloppy Mechanics


  • FukU2222

    (im)patiently W8n for 'daily' upload. But I guess there is still another ~3 hrs of daytime left on west coast....

  • Mark Regner
    Mark Regner

    Seems like that module is frequency dependent. What frequency did you try to run the pwm module at? Get a n02 solid state relay or relays and use the ecu to pulse it instead of that pos.

  • Username

    Where’s my daily upload ROBERT

    • Username

      @FukU2222 15 minutes left in the day

    • FukU2222

      ~3 hrs to go

  • Freshkryp69

    Type 9497929 into ebay or any OEM Volvo site.. Just 1 cools a 950hp GN.. Not brushless tho.. Or the 1000W BMW brushless fan, pwm @ 100hz.

  • Ryan

    TICK TOCK ROB, WHERE'S TODAY'S VIDEO???? I'm already spoiled. :3

  • Mike Novak
    Mike Novak

    Rob, whats the wiring on the fans temp sensor? Can you trash their sensor and run a output from your ECM to control the fans?

  • ツJaco

    That screeching sounds, sounds like when trains enter and leave the station. Although I actually find that noise cool 😎 and this on not fitting

  • iRdMoose

    Don't shock the system, put a 1 farad cap ahead of the relay. That way the cap takes the shock and doesn't interrupt cooling. Then, use inline coolant temp sensors connected to your ECU to detect the inlet and outlet coolant temp at the engine side. Easy peasey, no need for that crap PWM controller.

  • Gladiator 51
    Gladiator 51

    Did you say all of them were ground? Why would you worry about a short then you can't short to ground with a ground...

  • geeknow Z
    geeknow Z

    Dude the aluminum fabrication and welding was pretty sick! the pin holes may suck to patch up when welding on coolant but still pretty awesome 🤙

  • Mike d
    Mike d

    I've read to much coolant doesnt let your oil get hot enough for proper viscosity to lubricate and go threw tight tolerances.

    • FukU2222

      Not with rotaries

  • Jake Powell
    Jake Powell

    Is that a bmw water pump ??

  • Chris Moore
    Chris Moore

    There’s alternator shops that make hi-output Versions…

  • XxRaceBoy24xX

    Sounds like a PDM is in order for the 3 rotor now too.. just means even more wiring and programming, but at least component quality would be much less of an issue. Plus getting the system to behave exactly as desired

  • Strong man
    Strong man

    Hey Rob what do you use to connect wires to things because you said you don't like crimp connectors.

    • FukU2222

      There are lots of better crimp options

    • FukU2222

      He doesn't like THOSE crimp connections

  • marcus isaacs
    marcus isaacs

    Another first class explanation by first class guys 👍👍👍

  • Paweł Grządka
    Paweł Grządka

    Rob, a small observation on the radiator arrangement. With the internal suction pipe installed, the top half of the radiator will be a giant air pocket, that you will not be able to bleed. Please consider a bleeder on the top of the radiator. Greetings from Europe.

  • Chinh Tran
    Chinh Tran

    "fly a plane if he wanted to" 🤣🤣🤣

  • Randy Stull
    Randy Stull

    Lmao......when a backyard mechanic pretends that he can even remotely understand engineering.......typical of people today.....everyone knows everything about everything.

  • BNRGTR32 radGTR
    BNRGTR32 radGTR

    All I heard was 6 rotor twin turbo F1 car and all the boost maybe throw in 2 superchargers to help the spool boys cmon there is so much technology OUT NOW

  • Matthew Gunter
    Matthew Gunter

    I bought the exact same fan kit and was extremely underwhelmed with the mounting material. Taking them out next week and also doing a custom shroud to fit a new radiator. I was under the impression they were running full power at 49amp though. Yours say 65?

  • KaTaKyTo HD
    KaTaKyTo HD

    bor, i need to know where he got the yellow corvette t-shirt ,its fire !!!

  • anthony montague
    anthony montague

    12:22 the only time I’ve heard rob say pulling out and it not be a sexual innuendo

  • Kurt Sumthinorother
    Kurt Sumthinorother

    You want it on the water going into the motor, unless you are going to reprogram the controller, otherwise it will never shut off. Duct the air coming out of the radiator out a hood duct. Allow air not going through the cooling system to enter the front and exit out the back of the front fenders. Allowing the air to go through an air superheater, aka radiator, then flow over the motor is fighting against itself. That's why having a radiator width duct going up through the hood is so much better. Taking air from above the splitter and passing it under the air superheater, aka radiator, and purge the heat from the engine compartment will drop underhood temps by 50 degrees or more.

  • coco Boo
    coco Boo

    Need a disclaimer before messing around with the lift it's not a toy yall are semi professionals

  • Muhammad Ali
    Muhammad Ali

    10:56 he said it right there😂😂😂

  • Martin Balle
    Martin Balle

    Hey Rob. I think you need a air vent on your cold side of the radiator. With that pickup tube in there how are you going to get the air out of the system?

  • Mike oneill
    Mike oneill

    i love how polite you r when u being so blunt about a product that isnt up to par wel done ol chap

  • Amit Singh
    Amit Singh

    Fuck it just by pass everything lol

  • Honza Strnad
    Honza Strnad

    Just get the solid-state relay and do your own control from ECU :)

  • Iain Burgess
    Iain Burgess

    Did you put a vent in where the air collects in the rad system? Did you replicate the air bypass that Isaiah pointed out when unboxing the fans?

  • Kish - XxLK969xX
    Kish - XxLK969xX

    Nothing is stronger than family.

  • STIling

    I'd look at getting a little Saur Danfoss 12pin I/O module for your fan system. You can put a thermostat on and write some code (it's actually really easy to do) to control your fan smoothly. They even have PWM control. The connectors and terminals are really easy to source (mouser and digikey both carry Deutsch products) and they're all German so they're great quality.

  • Thatguywithnopancreas

    We're used to wires everywhere on your builds

  • Thatguywithnopancreas

    That sounds like a relay screaming lol

  • Thatguywithnopancreas

    Hey Rob,Joe here would you possibly be willing to help sponsor me with my 88 10thAE RX-7 I've had 23 years, I really could use some help with this car...Being disabled and trying to fund even just the parts for my #1Bucket list wish which is to drive this car just even 1 more summer while I can...No pity party ,but it would mean the world to me...💪🏾💪🏾💙💜Joey from N.H

    • FukU2222

      Rx7club Lots of info there. Check 2nd Gen section, make use of search feature/function

  • Eric Nelson
    Eric Nelson

    Hello, I have been researching PWM fan controller's. On several sites they keep mentioning, Delta Current Control, manufacturer of high performance cooling system components, American designed and made only in the United States of America. They have a few options and they build to order. (support@dccontrol.com) (from their website) Our constant temperature, full variable speed controllers have long been considered the best on the market. They can be utilized with virtually any cooling fan and employ pulse width modulation in order to set the fan to any speed in order to attain a constant temperature without cycling, regardless of driving conditions. I Do Not Work There I just want to share some information I found. Most people found that all of the big names in cooling source their components from overseas and it is very disappointing after spending a lot for a big name and it just doesn't work.

  • JK F1
    JK F1

    Is dude still banging what's her name?

  • Trevorcraft71

    Dont stress too much about trying to daily upload, id imagine automotive work is VERY hard to get done quick so just post at the pace yall want!

  • Theodor Nielsen
    Theodor Nielsen

    It’s pulse width modulation I don’t like how you say you need to stop adding more and more radiators and need a good fan the truth is it depends on what speed you are driving and if you have good air flow. Air flow also matter for a fan but it is more forgiving

  • Ali Abdallah
    Ali Abdallah

    Rob: my car's overheating! Also Rob: *cuts off part of the radiator* Yes, very wise.

  • Drift

    that water pump its like on my bmw e90 it cost me 300$ to replace it has a limited life span and when its gone it started draing the battery don't know why

  • Richard

    Azeia's spit on the radiator pipe was spot on :D :D


    you cant find pinholes on the radiator??? pressurize it and shoot it with soap. boom, 3 minutes located and done

  • Richard

    That radiator could use some servicing and flush haha :D



  • Jaydaks rules
    Jaydaks rules

    you should put a purge valve on the top of that radiator.

  • jib jib
    jib jib


  • Samy Tammpere
    Samy Tammpere

    Install water jet ahead radiator, when engine gets hot spray water on radiator. It helps to bring temperature down realy fast. Mitsubishi uses it on evo cars to bring intercooler temp down for better performance on hot contition.

  • Luke Trueman
    Luke Trueman

    So when are we going to see a billet Rob Dahm intake

  • Marshall Kell
    Marshall Kell

    8:56: me: "air." Rob: "you're probably wrong" me: "oh.. u_u " Rob: "it's air" me: "OH"


    19:07 sounds like a PS4 pro trying to play minecraft

  • GordoWG1 WG1
    GordoWG1 WG1

    YES!!! A properly designed fan shroud! That extended pickup is a darn smart idea, not sure about the application and packaging but one of the big advantages of an electric water pump is it can be placed almost anywhere - my personal preference is low down and drawing from the cold side of the radiator to the engine. The pump runs cooler than on the hot side drawing from the engine and pumping into the radiator, and it means as long as there's enough coolant to immerse the pump inlet, it'll be providing some circulation. having it at the highest point hurts my head, even with that internal extension. 100% agree about exposed terminals like that, I'd certainly be using a fuse, circuit breaker, or I think you're using a PDM which can be set to monitor the current draw and reset before cutting power. Same with the coolant pump sensor - it's all very well monitoring the coolant entering the engine, but that's not much help if the coolant is then flash boiling in the engine before condensing to a low temp' in the radiator. That said, it will depend a lot on the specifics of the setup being used.

  • nastystang113

    Sorry Rob you’re wrong on the “fuse”. That is a circuit breaker and there is nothing wrong with it. These are used in tons of off-road vehicle fan setups. I don’t like how that box is assembled either. I would be adding a lot of heat shrink with glue to all of those wires and maybe consider using some liquid electrical tape on them. I agree 110% with you on those shitty ass terminals. The best thing anyone can do that is messing with automotive, off-road, etc wiring that you actually care about is to buy a big assortment of 3M heat shrink electrical terminals. If you want to go all out there are ones called solder n seal that are the fucking best. Highly recommend. Another nice product are the Posi-Taps that come in splice style and tap style. I like to keep on me in the vehicle so if something does go wrong out on the road I can easily fix it and have a super strong and high quality connection.

  • Dale Bickham
    Dale Bickham

    Such a cute couple

  • JaredKaragen

    Rob; the thermostatic switch ALWAYS goes on the outlet side of the radiator (cold side). Check any manufacturer's OEM setup...

  • HypoFusion Gaming
    HypoFusion Gaming

    if the fans are making that noise when trying to override/ jumpstart them by shorting it out get rid of the controller its fucked, the fan motors will burn out. Not to say I'm a professional but I'm an electrician or a sparky as us aussies call yourselves and I work on fans and big motors all the time. If a motor makes that noise.. turn it off, either the fans cooked or something controlling the fan speed and rotation is wrong. Extensive periods of high frequency noise will burn them out.

  • Rooey

    Is it a 12v nominal battery? Because if you're getting 14v from the charger that would potentially be the problem, as it sounds like a mosfet oscillating as the voltage drops. As both circuits have a resistance you're making a divider, it goes below the voltage threshold for the PWM controller making it turning on and off at a highish unstable frequencies, hence why if you bypass the PWM controller it turns on and if im correct it will flow higher off the alternator than off the charger just due to the fact that its not seeing the full voltage. In Fact if I am correct and we use the variables 12.5v shutoff voltage and 14.7v alternator voltage we get: 14.7-12.5 = 2.2v extra 12.5/2.2 = 5.68 times less than cutoff 1+(1/5.68) = 1.18 (118% extra voltage) 1.18^2 = 1.39 times more power going to the fan (P = (V^2)/R, R ~doesn't change) But that's my guess, based off over a decade of electrical engineering experience. My question though is why use their controller at all, why not put your own NPT sensor on the hot side and have the ECU control a 100a SSD relay via PWM signal with a sensor that you trust?

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