Super Cheap Auto Castrol Edge Michelin Go Fast Bits Shannons Insurance Haltech Ryobi Century Batteries WD-40 KYB NTK NGK Spark Plugs

Announcement

Collapse
No announcement yet.

Electric Supercharger Install + Testing + Q&A

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    Fair enough point.

    I'll be interested to see what the data shows and just how much drag is generated from sucking it through the turbine, if it's noticeable.
    Until that point, I'll just shelve my self taught fluid dynamics :P

    An interesting consideration if you're finding your readings aren't accurate enough, is an engine torque sensor similar to what's in the new v8Supercars, measuring the actual engine output.
    Something like http://www.teledyne-ts.com/products/fpt100.asp

    That said, it's probably just my OCD showing.
    1983 Porsche 944 (DIY Engine rebuild)
    Webmaster, tech and content guy at http://www.vmotorsport.com.au

    Comment


    • #32
      I just want to interject a little math into this discussion. Have you done any calculations to see what type of force is required to spin said compressor wheel at X rpm (resistance being non-linear as speed and pressure increases)? The issue with doing a gear reduction on a motor, at say 20:1 to multiply the RPM's by that figure, is that you also divide the torque output by that same figure.

      Example. You have an electric motor capable of 10lb-ft that can spin out to say 15,000rpm. You need to spin the compressor wheel to 150,000rpm in order to achieve the desired pressure ratio/airflow requirements you are aiming for, so in order to do that you run a 10:1 ratio between the motor and compressor shaft - thus achieving 10 revolutions for every 1 of the motor. However, you also just reduced the torque output seen at the compressor side from 10lb-ft at the motor, to 1 lb-ft at the compressor shaft.

      Just something to consider. The last viable electric supercharger actually built for mass market was essentially an eaton twin screw with two to three electric starter motors driving it. It pulled so much power that you had to run an extra battery, and the supercharger could only be engaged for a couple of minutes before you ran the batteries flat.
      Daily Driver/side project - 2005 Ford Crown Victoria
      Full Project - 1988 Isuzu Impulse Turbo.

      Comment


      • #33
        Originally posted by Fara View Post
        An interesting consideration if you're finding your readings aren't accurate enough, is an engine torque sensor similar to what's in the new v8Supercars, measuring the actual engine output.
        Something like http://www.teledyne-ts.com/products/fpt100.asp
        heh. I think you're FAR overestimating my access to resources. Remember that at the end of the day, I'm just some chucklehead with a website and a pretty good layman's knowledge of engines and boost. Now, if you can convince the nice folks at Teledyne that they'd really benefit from an independent test of that torque reading gizmo, and one were to show up at my house with a bunch of instructions on what to do with it, then I suppose we could kill two birds with one stone here. More likely though, some day in the future, maybe I'll do a dyno test and we'll see some actual power difference testing. That's not currently in my plan though and honestly not necessary for what I'm doing.

        Can we all agree that if we get positive boost through the entire rev range, that we can absolutely make more power? That's a given, right? And can we also agree that none of the scammy electric turbos on the market can actually do this?

        So if my testing shows that this thing CAN produce appreciable boost all the way through the rev range, then that makes it a success, right? Now... tuning it to get the most power out of the engine is a whole different ball game, but that's the case for any turbo or supercharger or NOS kit for that matter. My car already knows what to do with boost, so I've got no concerns there. Obviously anyone buying this thing as a product to install on an NA car needs to be aware of that sort of stuff. But IF IT MAKES BOOST then there's gains to be had, right? That's ultimately the question I'm looking to answer here to give my PASS/FAIL conclusion. And judging by my test run on the weekend, I'm quite optimistic.

        Originally posted by ImpulseRocket View Post
        Have you done any calculations to see what type of force is required to spin said compressor wheel at X rpm (resistance being non-linear as speed and pressure increases)?
        I haven't. None at all. I figure that if I'm getting boost, then it's producing enough torque. Is that reasonable?

        Originally posted by ImpulseRocket View Post
        Just something to consider. The last viable electric supercharger actually built for mass market was essentially an eaton twin screw with two to three electric starter motors driving it. It pulled so much power that you had to run an extra battery, and the supercharger could only be engaged for a couple of minutes before you ran the batteries flat.
        Right. And that was quite a few years ago. I'm not sure if you're writing this to suggest that this is a ridiculous idea or just to point out how much trouble it took to get those gains. What I've got right now is essentially this exact same thing, but using current technology. Instead of an eaton, I've got the compressor side of a turbo. Instead of three starter motors, there's just one motor. And I've got an extra batter (2 actually) to run it. I'm not sure how long it will run until the battery is down, but my impression is that it's over a minute but probably not two. That doesn't sound like much, but when you think about it... how long do you ever sit at WOT? From standing still, my car will run the quarter mile and get to over 93mph in less than 15 seconds. So if the thing recharges at a rate of 7:1 as I'm told... and even if we double that... would you ever run it out of battery?

        Now... before we get carried away here... those numbers about run time and recharge and all that are all directly from Rob and I haven't done any testing or anything to validate them yet. But if they hold up, then wouldn't this all be a roaring success?

        I know I'm playing a bit of devil's advocate here with the arguments for it. It's actually a bit of fun for me since I've only ever been on the other side of this discussion. Please don't be ready to toss me under the bus just yet. All of this is predicated on the blower doing what I'm expecting it to. The results are promising so far, but you never know what might happen.

        My next step is going to be another run with just the M45 to try to get better data points, and then a run with the M45 disabled to prove that the bypass is working as expected.

        I've still got 5 year old gas in the car with 5 year old fuel stabilizer and a new can of Sea Foam. I haven't had any discernible knocking or thrown a code or anything yet. Am I missing something here? Can anyone point out any concerns I should have or, as it's run ok so far, do y'all think I'm in the clear? It's occurred to me that trying to burn off 3/4 of a tank of fuel by driving around the block at 40km/h could take an awful long time and I'm not too inclined to just drain it out and have 30+L of gasoline sitting around.
        sigpic

        Comment


        • #34
          Originally posted by Wild Weasel View Post
          Right. And that was quite a few years ago. I'm not sure if you're writing this to suggest that this is a ridiculous idea or just to point out how much trouble it took to get those gains. What I've got right now is essentially this exact same thing, but using current technology. Instead of an eaton, I've got the compressor side of a turbo. Instead of three starter motors, there's just one motor. And I've got an extra batter (2 actually) to run it. I'm not sure how long it will run until the battery is down, but my impression is that it's over a minute but probably not two. That doesn't sound like much, but when you think about it... how long do you ever sit at WOT? From standing still, my car will run the quarter mile and get to over 93mph in less than 15 seconds. So if the thing recharges at a rate of 7:1 as I'm told... and even if we double that... would you ever run it out of battery?

          Now... before we get carried away here... those numbers about run time and recharge and all that are all directly from Rob and I haven't done any testing or anything to validate them yet. But if they hold up, then wouldn't this all be a roaring success?
          I am doing neither. I am writing this from a purely objective point of view. A couple of years ago I actually had this idea myself, but never really got around to experimenting with it, so I am quite keen to see what results you could get. The idea itself is sound, but the application is much more difficult to pull off.

          Just something I wanted to throw out there for consideration is all. I just wanted it to be considered that contrary to popular belief, a turbocharger compressor takes quite a bit of energy to spin up the the rpm's needed to create enough airflow at positive atmospheric pressure and hold it there.

          Also, something else to consider for your experiment, holding a constant RPM at the compressor will most likely cause boost pressure variances across the RPM range, so some type of potentiometer that references a tach signal to control speed might be handy - assuming you do get it to work.
          Daily Driver/side project - 2005 Ford Crown Victoria
          Full Project - 1988 Isuzu Impulse Turbo.

          Comment


          • #35
            If this doesnt work, one day in the future it would be awesome to see the same idea used but to electrically pre-spool an exhaust turbo and reduce lag

            Comment


            • #36
              Originally posted by ImpulseRocket View Post
              Just something I wanted to throw out there for consideration is all. I just wanted it to be considered that contrary to popular belief, a turbocharger compressor takes quite a bit of energy to spin up the the rpm's needed to create enough airflow at positive atmospheric pressure and hold it there.
              Yep, and this is why just about everything out there is a scam. It's just not easy to accomplish.

              Originally posted by ImpulseRocket View Post
              Also, something else to consider for your experiment, holding a constant RPM at the compressor will most likely cause boost pressure variances across the RPM range, so some type of potentiometer that references a tach signal to control speed might be handy - assuming you do get it to work.
              This is why I'm expecting the boost to taper off through the RPM range. We were having this discussion on the TM3 forum, and I suggested that even if it's making 4 psi in the middle of the rev range, if it ends up tapering off to less than 2 at the end then it might be a cool proof of concept but that it probably wasn't all that worthwhile as a mod. Then, a few days later, the bigger one showed up.

              As I understand it, this thing is going full-bore once it's turned on, so it's producing as much boost as it can, which therefore has to go down as the engine runs faster and consumes more air. Apparently the small one is intended for smaller engines than mine, so it may not have kept up to the arbitrary target I set. The big one is probably too big for a 2.4L so it's likely to make 6+ psi on the low end, which would almost certainly throw a code on a regular engine. Mine's set up for boost though, so it'll be just fine and certainly prove the concept. If it's provable.

              We've had some discussion about how to get even boost through the RPM range. Whether it's measuring it and controlling the voltage, or just using a bigger one and having a relief valve in front of it, there are definitely options. None of them are on the table for this POC though.

              Originally posted by pretzil View Post
              If this doesnt work, one day in the future it would be awesome to see the same idea used but to electrically pre-spool an exhaust turbo and reduce lag
              This is actually already in the works. I talk about it a bit on my website. BMW has been working on exactly this concept. Now... if you think it would be a cool aftermarket option, I'm gonna go out on a limb here and just about guarantee it'll be hella-expensive. It's difficult enough to spin a compressor with an electric motor. Now you want to do that while dealing with turbine temperatures?? That's not gonna be cheap.
              sigpic

              Comment


              • #37
                Originally posted by Wild Weasel View Post
                I haven't. My "test rig" is my car, and all I've done so far is a few full-throttle pulls on a side street. To be honest, I'm not sure I'm going to be able to test this at all. Unfortunately, I can't go out on a nice highway run since I'm just not insured for it and am not looking at taking any undue risks. I've driven the car around the neighbourhood, but that's the extent of it. I don't want to cause trouble for myself or anyone else.
                SO... I made some calls.... and it turns out I can get a temporary 10 day permit for pretty cheap so I WILL be able to go beyond the neighbourhood and really run this thing out of battery to see how long it lasts and what not. It won't be this weekend, but I'm hoping I can schedule this for the weekend after. I want to ensure I've got at least a full weekend to devote to this before taking this step since I don't think I can do it more than once or twice in a year before they'll expect me to get permanent plates.
                sigpic

                Comment


                • #38
                  Just a quick update. I'll be fully insured for this weekend and next, so I should be able to get some good data on how long the batteries last and what not. I'm also hoping to go through all the tests I set out to do so we'll have plenty to discuss beyond just the teasers from last weekend and the speculation.

                  I know this forum is mostly based Down Under... but if there's anyone in the Toronto area that's interested in seeing this stuff running in person, please let me know and we can arrange to get together!
                  sigpic

                  Comment


                  • #39
                    Even if this did work, how are there any benefits over a typical centrifugal supercharger that works off engine power and already is proven to be super effective?
                    1982 Toyota Corolla KE70 - Build Thread
                    2004 Subaru Liberty Sedan EJ25 5sp Manual - Current Daily Thread
                    1994 Toyota Corolla Hatch Csi Ltd. 4AFE 4sp Auto - Sold 25/01/13
                    sigpic

                    Comment


                    • #40
                      Originally posted by Wild Weasel View Post
                      I know this forum is mostly based Down Under... but if there's anyone in the Toronto area that's interested in seeing this stuff running in person, please let me know and we can arrange to get together!
                      Damn. I'd be keen to see one of these things first hand and be part of the testing.

                      Originally posted by ThePotatoSmasher View Post
                      Even if this did work, how are there any benefits over a typical centrifugal supercharger that works off engine power and already is proven to be super effective?
                      There probably aren't many benefits, other than the electric supercharger being more of a 'plug and play' solution, compared to normal superchargers that need a lot more work to get up and running.

                      Comment


                      • #41
                        Originally posted by Jenga View Post
                        There probably aren't many benefits, other than the electric supercharger being more of a 'plug and play' solution, compared to normal superchargers that need a lot more work to get up and running.
                        Eh proven results wins over most things for me personally...
                        1982 Toyota Corolla KE70 - Build Thread
                        2004 Subaru Liberty Sedan EJ25 5sp Manual - Current Daily Thread
                        1994 Toyota Corolla Hatch Csi Ltd. 4AFE 4sp Auto - Sold 25/01/13
                        sigpic

                        Comment


                        • #42
                          Interesting idea. I know there are some pretty massively powered BLDC motors available for RC applications. Some up toward 20kw, which is only feasible if they spin to insanely high RPM (since P=T*w).

                          If I were to do it, I'd not be using SLA batteries though. 8 of these (http://www.evworks.com.au/index.php?...t=BAT-SE060AHA) Lithium batteries would give you the same voltage, but much less sag under load and higher capacity. There are smaller ones available as well. Since they're being charged by the control box, then there's no worries about short circuits, etc when charging. That's the main reason lithium isn't used in cars normally, because attempting to jump start a flat lithium is like shorting the battery in the car you're connecting it to.
                          My Facebook page - My YouTube channel - mauswerkz on Twitter
                          The mauswerkz 300zx EV build thread.
                          My 1992 BMW 318is Coupe, soon to be battery powered. Technical progress in this thread.
                          sigpic

                          Comment


                          • #43
                            Originally posted by ThePotatoSmasher View Post
                            Even if this did work, how are there any benefits over a typical centrifugal supercharger that works off engine power and already is proven to be super effective?
                            Well... a centrifugal supercharger is an odd sort of a thing, but I think what you're looking for are the benefits over a traditional supercharger or turbo. Frankly, it's cost and ease of installation. If you can afford a proper supercharger or turbo and are willing to do the extensive mods for the install, I can't imagine why you'd want something like this. Well... unless you're the one guy on JBO whose got as small a pulley on his supercharger as he can fit and still wants more boost. I think he's the only person in the world who's keenly interested in my runs with both the ESC and M45 going. But he's an anomoly.

                            Originally posted by Jenga View Post
                            There probably aren't many benefits, other than the electric supercharger being more of a 'plug and play' solution, compared to normal superchargers that need a lot more work to get up and running.
                            That really is the benefit right there. If you can get 20% more power (or more) without too much effort, who wouldn't want that, right? That's what draws in all the suckers to all the scams. If you've got room under the hood for it, installing this thing was really a breeze. Now... which engines might be ok with a few lbs of boost and take advantage of it, and which can't keep up with the fueling and would have problems... that's a whole other issue. But that has nothing to do with this test of "DOES IT BOOST??"

                            Originally posted by mauswerkz View Post
                            If I were to do it, I'd not be using SLA batteries though. 8 of these (http://www.evworks.com.au/index.php?...t=BAT-SE060AHA) Lithium batteries would give you the same voltage, but much less sag under load and higher capacity. There are smaller ones available as well. Since they're being charged by the control box, then there's no worries about short circuits, etc when charging. That's the main reason lithium isn't used in cars normally, because attempting to jump start a flat lithium is like shorting the battery in the car you're connecting it to.
                            Well... if the batteries really hold up to a minute or more of boost and can recharge in a reasonable time, then they should suffice. Of course, lighter is always better. That's interesting about the issues with lithium batteries though. I'm sure I've started to see them trickling out for sale now, especially for motorcycles. I didn't know they had these issues with charging though.
                            sigpic

                            Comment


                            • #44
                              Originally posted by Wild Weasel View Post
                              That's interesting about the issues with lithium batteries though. I'm sure I've started to see them trickling out for sale now, especially for motorcycles. I didn't know they had these issues with charging though.
                              Yeah, they show up more for motorcycles, and there's probably some for cars too. The problem with using them in cars (or even bikes) is their low internal resistance. If you apply 14v across a flat lithium battery, it will pull hundreds of amps, practically like a short circuit. Lead acid batteries have relatively high internal resistance, especially when charging, so at worst you get a little bit of a spark when connecting the leads, and the current is limited by the resistance. Not sure what type of protection (if any) 12v lithiums have built in against this. I only work with the individual cells myself.
                              My Facebook page - My YouTube channel - mauswerkz on Twitter
                              The mauswerkz 300zx EV build thread.
                              My 1992 BMW 318is Coupe, soon to be battery powered. Technical progress in this thread.
                              sigpic

                              Comment


                              • #45
                                IMHO, I think the real benefit if this was a viable solution is the same reason so many people buy the fake useless ones sold on e-bay. Some people just want to get a little more power out of the car without spending $5000+ to install a turbo or supercharger system. Relatively low pressure ratios are safe for almost all factory computers/engines, and even 4-5psi of positive manifold pressure from a large enough compressor will make quite a significant bump in power over stock. Hell, It would be kind of nice to have on my daily driver, something for those times where a bit more power would be nice, but as a whole I really don't want to mess with it.

                                Imagine, if you will, a product that (realistically) would cost you about $1000. The work required to do it is something anybody could do in their driveway in a few hours or less, and the potential is there to gain upwards of 25% more power. There is the appeal. Making it actually work is the hard part, but not impossible. The theory is very sound, and as was already pointed out, the technology now is much more capable of making this a reality than it was even 10 years ago.

                                IMHO, I would love to see this done with a modern billet wheel from a turbo like my 7670 EFR or old PTE 5431 CEA/MFS. Much better aero, efficiency, and lighter mass means a motor would be doing less work. Heck, use a universal shift light and set the power to the LED to trigger a relay that powers up the system and you could select what RPM it came on at too.
                                Daily Driver/side project - 2005 Ford Crown Victoria
                                Full Project - 1988 Isuzu Impulse Turbo.

                                Comment

                                Working...
                                X