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jon dee

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Everything posted by jon dee

  1. Makes you think... https://www.washingtonpost.com/nation/2022/06/22/tesla-fire-sacramento/ Cheers...
  2. The vehicle is "stationary" for 18.9% of the 1369 second test duration.. Now you know Cheers...
  3. Fair comment. Delving into some of the more informed descriptions of how stop-start technology is controlled, I see that one of the safeguards is that the system will be deactivated if battery voltage drops too low or if the engine temperature is too low. So while the amount of energy required for each engine start may be small, it still has to be restored, and regenerative braking is probably the only way to get that energy without using fuel. Yes... turning the engine off does save fuel, but as was shown in the research paper I referenced above, turning it back on again does use a little bit of extra fuel. A hot engine requires a richer mixture to ensure smooth starting and this can be seen by the dip in lambda. The net gain in fuel saving depends on how long the engine is turned off before being restarted. Cheers...
  4. WOW..... just WOW Kevin, I suggest you take a few hours to calm down and then read what you just wrote. You are indulging in the very behavior that you are ranting about. Classic example of the Straw Man Fallacy... you make assumptions and unfounded assertions and then attack them All good. But to get back on topic, the fundamental justification for stop-start is that it reduces fuel use by turning the engine off when the vehicle is stationary. And the yardstick used is the urban driving cycle which conveniently contains a significant number of periods of idling. This is the target for the stop-start technology, and where the fuel savings are made. But if a vehicle's daily commute does not involve driving in heavy city traffic, but follows a flowing suburban route with few stop signs or traffic lights, the results will be very different from the standardised urban cycle. Taking this argument to its logical conclusion, driving town to town on the open road, the stop-start system will have saved zero fuel. So, as the saying goes.... results may vary. Cheers...
  5. That is a stunningly dismissive statement of what appears to be a genuine effort to document the effects of stop-start operation on various engine operating parameters. Quite frankly it sounds like something a Chinaphobe would say, but sobeit. If a 16yo can produce something like that then the world is in better shape than I thought Cheers...
  6. It's only physics son... nothing to be frightened of This is what real research looks like... https://www.e3s-conferences.org/articles/e3sconf/pdf/2021/44/e3sconf_vesep2020_01030.pdf Cheers...
  7. If I was interested enough I would want to see the original test data and methodology used. That guy is just a youtuber who makes a living out of presenting basic science to uncritical audiences. He did not make the actual tests. For example, every time the starter cranks the engine it draws energy from the battery. That energy is restored by the alternator putting extra load on the engine, and that requires extra fuel to be burned. Was this factored into the original test data ? Small four cylinder engines can be expected to be more fuel efficient that larger 6 or 8-cylinder engines. How would this affect the results ? Until proven otherwise, youtube videos are not worth the paper they are written on Cheers...
  8. And for all of you "big bore" exhaust fans... meet the master blaster Cleared for takeoff ?
  9. Found it !!! Rarer than rocking horse teeth.... 1951 Buick Le Sabre concept car.... now you know
  10. One for the car guys... InWBeS5.mp4
  11. The internet represents the first phase of AI replacing human intelligence. There are already many millions of people who have made the shift and now allow the internet and socmed to do their thinking for them. The constant burden of having to think for oneself is removed, and there is no longer any need to consider the consequences of ones actions. After all, the internet knows everything there is to know and socmed with its demigods provides the necessary link between the brain dead and the internet. When Trump rises again in his final incarnation, the transition to AI will be complete. Hordes of New Age zombies will overrun governments and and like the Mau Mau, using drugs to make themselves invincible, they will sweep the last thinking people aside. This is no laughing matter... I saw a video on TikTok that explained it all !!! Cheers...
  12. Without any specific knowledge of the car in question, I think that if the shifts are fully controlled by a transmission computer, it will protect against user error. My car is a 2008 model and it will not downshift if making the shift would result in excessive engine rpm. And I have seen a YT video of someone purposefully shifting a reasonably late model Honda (I think) into reverse at 100kph to see what would happen. Nothing happened... the trans did not shift into reverse, and there did not appear to be any ill effects. So based on that exhaustive investigation of barely any facts, I think your trans controller should keep you safe. Curiously enough, I find that operating the wipers just before I make a turn doesn't always get me a cheerful wave from other motorists Cheers...
  13. These guys seem to have put a bit of thought into the design of an intercooler setup that will handle track work. Getting maximum airflow through the cooler by using a bit of cunning ducting is very much a part of racecar design. I don't know how much cutting away of factory plastic is involved, but again, you don't want your bumper/number plate etc interfering with airflow. http://www.evolutionracewerks.com/node/50 Cheers...
  14. Jackson Street, Petone this morning. Thought it might of been a BM except missing one kidney
  15. I worked with a guy who had some kind of BMW racecar and I know that he was forever repairing / bracing rear subframes. Seems to be a well known issue with certain models but I don't have any specific details. Obviously there are issues with IRS that don't exist with live axle vehicles, and there is likely to be a lot of information on the causes and fixes posted on BM forums around the world. Solid bushings are the ultimate fix for racecars, but are not recommended for any car that is used on the road. Compromise is the name of the game if you need to drive to the track. So as suggested above, poly bushes may do what you want. Just make sure to get quality bushes from a reputable manufacturer. Good luck Cheers...
  16. Quiet night so why not post an answer to a question that was not asked I'm not familiar with the bushings in question or the forces acting on them. If the loads are pure compression then either of the bushes you have linked will do the job. However, if the loads involve impact, twisting or rotation increasing the stiffness may transfer forces and induce binding or bending into other suspension components. Rubber bushings typically add spring rate to suspension arms and operate without lubrication. UHMWPe is self lubricating but urethane requires lubricating when used in pivoting joints, and neither add spring rate. Just to provide a basis for endless debate, here is a small chart with my comparison of the NVH effects of different types of rotating bushes used in suspension arms... Entirely subjective as NVH will vary with suspension design, bushing hardness and whether the vehicle has the full factory interior or if it has been gutted etc. If suspension arms only have movement in a single plane then hard bushing are fine, but if the arm "twists" as the suspension travels through its range of movement, the OEM rubber bushings may have been designed to absorb the twist. If that is the case, then hard bushings will transfer loads into the chassis or subframe, and these forces may be strong enough to break welds of tear metal brackets. Probably an irrelevant post, but if I wasn't typing this I would be shaving my legs and getting ready for a night on the town Cheers...
  17. From the Motorsport Manual... From this it would appear that a standard stock every day road car is not required to have tow eyes. However, to be safe you would need to check the regs for the event and if necessary, confirm with an event organiser or scrutineer. For what it is worth, I actually got an extra OEM BMW tow eye and used one front and back. As if you put your car in a ditch you can't always choose if it goes in front first or back first, and having somewhere obvious to attach a rope might save some damage. Incidentally, if towing eyes are required, to meet Motorsport NZ regulations they should have a minimum internal hole diameter of 40mm to be legal. This means that the OEM BMW toolkit screw-in tow eyes are not legal. So basically you would just be providing them voluntarily Cheers...
  18. I don't know what sections of the main trunk are currently using electric locos. But chances are that diesel locos are widely used for marshalling and for non-electrified routes. Political window dressing versus practical operational issues. However, now that we are in the grip of another fuel crisis the government is casting around for ways to meet its overly optimistic climate change commitments. So the formerly neglected and unwanted main trunk electrification project will finally have its day in the sun Cheers...
  19. I believe that the main trunk rail line Wellington-Auckland is electrified. It was one of the governments "Think Big" projects back in the 80's at the time of the last big fuel crisis. Recently KiwiRail wanted to change back to diesel but the government said they needed it to stay electric to help them try and meet their climate change emissions goals. Cheers...
  20. OIC. Sentence is a little ambiguous and contains the word "load". Did not make it immediately clear that it was referring to contributing power to the grid rather than taking power from the grid. Thought it might have been referring to Tiwai (which would be a load) but then AFAIK Tiwai is not connected to the national grid so my bad Uses carbon electrodes to make fire though Got a lot to learn about energy pricing, but the one thing I do know (as mentioned above) domestic consumers are going to get screwed no matter what happens. The competition that was supposed to hold prices down just means you now have a choice as to which company you get screwed by !!!!! Cheers...
  21. Can someone please explain to me how a "gas burner" can be a load on an electrical grid ? Cheers...
  22. But Hamsters look like they are having fun.... not sure about this guy ?
  23. Love the DIY concept only can't help but think that a hipped roof would help with the drag coefficient Cheers...
  24. jon dee

    Quick rant thread.

    Just in case you are feeling down and need a quick fix Cheers...
  25. jon dee

    Quick rant thread.

    And the mournful wail of two-stroke engines will no longer be heard on Sunday morning calling the faithful to their lawns and hedges... the valleys will be silent... the scent of the line trimmer and chainsaw gone forever... nothing more than a memory spoken of in hushed tones when old men gather to reminisce about the sins of their youth... Cheers...
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