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JFP in PA

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Everything posted by JFP in PA

  1. JFP in PA
    The Li battery business is suffering from a similar problem that the light bulb business had when switch from incandescent to LED. People had long associated bulb wattage with light level output, even thought wattage was actually measure of how much energy the bulb consumed and heat it generates rather than light output levels. So when consumers saw that an LED replacement for a 7 watt night light bulb only used 1.3 watts of power, their immediate assumption was that the LED would be much dimmer in light output than the incandescent bulb, which was anything but correct; and that stalled acceptance of the LED replacements for a period of time. Fortunately, there was another widely accepted scientific standard for light output: Lumens So when comparing replacement bulbs, consumers discovered that a 25 watt incandescent bulb and a 3 watt LED bulb both produced 130 lumen, meaning they were equally as bright, and that a 40 watt incandescent had the same lumens as a 5 watt LED, consumers now had a sound and reproduceable way of relating the product specs to their needs. Unfortunately, no such relatable second scientific measure currently exists for comparing conventional batteries to Li based units amperage performance under the same conditions. As as shown by the comments I quoted above, even within Li battery manufacturers there is no mutually agreed upon "equivalency" standards that either the BCI or SAE could buy into, much less help consumers make purchasing decisions.
  2. JFP in PA
    He also went on to state that you could use their lightweight Li battery in a daily driver, "..as long as it is not used in cold weather.", without defining how cold that weather really was. Li technology for automotive use is a relatively new and evolving technology, and a very interesting one at that. But like most emerging tech, it still has a bit of the "wild west" in it that will shake out over time, but using "equivalencies" that seem purposely deceptive to sell the products is not helping their case any.
  3. JFP in PA
    Here is an interesting published statement by a representative of the Antigravity Li battery company about their use of "equivalency ratings" used by Li battery manufacturers: "Unfortunately for you consumers....the waters are muddy because none of the lithium battery company put the ACTUAL and REAL Amp Hour of the Capacity ON the Battery itself.... For example most of the battery companies including Antigravity go by a "PB-EQ" (means-"lead-acid equivalent") rating which is essentially stating what size our Lithium Battery is roughly equivalent to the Starting ability of a Lead/Acid Battery. And even this PB-EQ rating is not accurate because a company like Deltran, who makes the Battery Tender lithium battery version will state they offer a battery that they claim is equivalent to a "20 amp hour lead acid battery" yet the size of the lithium battery pack inside their battery is actually only 7 REAL AMP HOURS. At the same time a company like us, Antigravity, will claim we offer a battery that is equivalent to "20 amp hour lead acid battery" yet our lithium cell pack will be 12 REAL AMP HOURS... " I particularly like the "roughly equivalent" statement.
  4. JFP in PA
    If there is one thing all Li batteries do not like, it is being overly discharged (read deep cycled), which really damages them. This is why many newer Li batteries have a "BMS" or electronic battery management system included in their construction, which will step in and cut off the battery before it gets into an overly high discharge condition. Most Li battery BMS systems also include thermal protection as Li cells do not like getting very hot either.
  5. JFP in PA
    Li technology is very interesting, but also quickly evolving. One way to look at light weight LI batteries to to watch what happens with race teams at the track; most serious race cars run Li lightweight batteries with one major caveat: they don't use them to start the car, only to supply energy reserve while the car is running. For starting in the pits they hook up a conventional AGM battery: There are Li batteries that are fine for daily drivers, with high CCA ratings, but they are also not super lightweight and expensive because they are relatively low production item. Even Porsche released an Li battery for street use, but it was over $1700 at retail.
  6. JFP in PA
    But otherwise the underlying battery appears to be the same unit.
  7. JFP in PA
    They both appear from their dimensions and other specs to be the same battery ("Starter Battery - 68Ah EqPb lead-acid/AGM/GEL equivalent", etc.), but with different terminals.
  8. JFP in PA
    If it truly was, it would be purely luck. Interestingly the battery manufacturer's website says, and I quote, "up to 400CCA for ICE engines in HYBRID models with 900CA available at the press of the button" (notice we are jumping from CCA @ 0 F to CA ratings @ 68 F in that statement), apparently referring to its reserve cell capacity when a button is manually depressed, but at 68 F, not 0 F; and goes on to state, "Specifications: 68Ah PbEq, 400CCA with Push Button Reserve", so at 400 CCA (without the manual reserve button depressed) it has about 1/2 the cold cranking power of a conventional or AGM lead/acid battery of 800 CCA. As with most lightweight Li based batteries we have seen in the shop, it is low on amperage capacity. Every one we ever saw suffered from low capacity problems (headlights dimming when the stereo or AC was running, poor starting in cool/cold weather, etc.). There is no such thing as a free lunch. Have a nice holiday week end.
  9. JFP in PA
    Actually, it is not. You simply cannot take values for a smaller battery and extrapolate them to a larger unit, or visa versa. There are many other factors (internal conductivity, heat retention, cell pack, conductor resistance differences, etc.) that complicates such a mathematical solution attempt to the point of being unreliable. This is why battery manufacturers continually test their batteries to see how they rate rather than attempt calculated performance projections. If it was simply a matter of extrapolation, life would be a lot simpler in the battery business, they could save a whole bunch of money by not testing or having large test facilities, plus the technical consortiums (BCI/SAE) who's standards they have agreed to adhere to require actual repeatable test data rather than extrapolations.
  10. JFP in PA
    As someone that spent a significant part of his career in the battery business, your use of "assuming the proportions are the same" is more than seriously flawed. The CCA test used by the BCI (Battery Council International, the international technical consortium that sets standards for battery ratings and testing procedures used by battery manufacturers world wide) is very similar to the one used by the SAE (Society of Automotive Engineers); which requires storing the finished and fully charged battery a 0F (-17.8 C) for a period of 24 hours, then load testing it to determine its CCA rating. There is no known "proportioning" formula for determining this value, only hard testing data. Lightweight battery manufacturers have been "inventing" unique rating values and "equivalencies" without a basis in technical facts, and that are really totally meaningless, simply because they know what the outcome of publishing the more widely accepted testing data would be: Their batteries would appear weak compared to conventional SLI (starting, lighting, ignition) batteries.
  11. JFP in PA
    I would also like to know the unit's cold cranking amperage (CCA run at 0F after 24 hours), not the cranking amperage (CA which is done a 68 F) in the specs. A lot of these small, lightweight units are fine for race cars, but fall flat on their faces (literally) trying to spin over an engine at 20 F.
  12. JFP in PA
    We always did it on a lift with an engine support bar under it before we undid the mounts. You only need to drop it a couple of inches to make getting at it much easier, not out of the car. Usually, the nut on the ground is not in bad shape, and a quick spray with a good penetrating oil always helps. Just be sure to wipe it off before putting it back together again, and put a small dab of anti seize inside the nut.
  13. JFP in PA
    Depends upon how large your hands are, dropping the engine down slightly always gives you more room.
  14. JFP in PA
    Sounds like a vacuum leak.
  15. JFP in PA
    The correct test for the primary cables is voltage drop rather than resistance. No primary cable should show a drop of 0.5 V, if they do, they should be replaced regardless of what resistance testing shows.
  16. JFP in PA
    No, but hard clutch pedals in these cars is usually a sign the clutch itself is on its way out,
  17. JFP in PA
    Good luck, these types of issues are diagnostic time consuming; with luck you have a wiring or connector issue.
  18. JFP in PA
    Your next step would be to see if the DME is actually seeing any signal from the CPS, which requires a PST II, PIWIS, or similar oscilloscope diagnostic tool. You could also check the wiring harness for continuity to the DME; pin 1 on the sensor should lead to terminal 78 on the DME, pin 2 to terminal 20, and pin 3 to terminal 28. If any of those circuits shows a lack of continuity, you have a wiring issue.
  19. JFP in PA
    Unidentified sounds like this can be something small, like a loose part, or they could be something much more serious. Unless you can isolate the sound source, I would recommend not driving the car and flat bedding it to someone that can do more intensive diagnostics for you.
  20. JFP in PA
    I think the biggest obstacle you face is the leveling system, as even though you fit the mechanical parts, your DME does not have the programming to make it work, and even Porsche has proven to be reluctant to reflash the computer for this purpose. And without that, the car will fail inspection anywhere in the EU. The washer stalk does have a distinct cap which indicates the action required to activate the washers. This is a file done by someone that tried this, but it does not address how to get the DME functional: http://986forum.com/forums/attachments/performance-technical-chat/20080d1455322905-adding-headlamp-washers-litronic-retrofit-automatic-dynamic-headlight-beam-adjustment-minimum.pdf This may also prove useful: http://www.skylersrants.com/Porsche/Litronics/Instructions/Litronic11-02.pdf
  21. JFP in PA
    I am a "professional" that has run his own shop for many years, and my lawyer was advising me as a business owner, based upon multiple legal actions brought against similar businesses, and it two cases, individuals who did it for former buddies that later sued them for damages, and won big $. The potential consequences simply are not worth the risk. And no one here is offering legal advice, only our experience.........
  22. JFP in PA
    According to all the related industry literature I've read, and what my shop's legal consul has told me personally, it is a Federally mandated safety system, meaning that if you disable it, or show someone how to disable it, and the vehicle is subsequently involved in an accident, whomever did it (or showed someone how to do it) can be held both criminally and financially liable. And in many states, the vehicle is considered "unsafe" and would not pass local inspection standards. The same thing would apply to removing seat belts or disabling or removing the air bags. Proceed at your own risk..............................................
  23. JFP in PA
    Just take the bulb out.
  24. JFP in PA
    You can also look for a shop with a system called an “electronic ear”, which uses six separate noise sensors mounted at various parts of the car that can quickly triangulate an isolate the location of the sound. We have successfully use this system to locate very hard to locate sound sources.
  25. JFP in PA
    By far, the larger issue with the power steering systems on these cars is heat, not debris. More power steering pumps fail from overheating than anything else. There are a couple of aftermarket companies producing add on coolers because of this issue.
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