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  1. WhizzMan

    [Possible Causes?? of ] Cracks in exhaust system

    The question is, are these causes, symptoms, or both? Did your coolant levels drop because of overheating, or did the low levels make it impossible to cool the engine properly? Cracks usually occur because of either too much heat, localized hot spots or mechanical (vibration) issues. Since you...
  2. WhizzMan

    Transonic Combustion - SAE Paper

    How are you dealing with the increased peak pressures? You are essentially creating an engine that is pinging because of hot spots. This must be extremely hard on big end bearings.
  3. WhizzMan

    Pre-turbocharger methanol injection

    Is there a reason you keep running these smaller turbos? The obvious solution here would be to just put bigger turbos on. I think that if you reduce the pressure behind the turbo, the total amount of air flowed will still be the same. The turbo has to create a pressure difference between pre...
  4. WhizzMan

    Combustion Chamber Thermal Dynamics

    Would there be any significant difference if you would coat the inlet valves? I doubt they would heat up from the cold air/fuel mixture, so it would only be blow-back during overlap that would heat them. I don't see a benefit of coating anything else than the "inside" of the dish of the inlet...
  5. WhizzMan

    Twincharging - calling Warpspeed!

    After some more reading, it turns out that the predecessor, the Lancia S4 had twin charging, the ECV1 has 2 turbo's.
  6. WhizzMan

    Twincharging - calling Warpspeed!

    Someone directed me to the site of the Lancia EV1. Since it's in Italian, I put the translate link of it here. http://translate.google.com/translate?js=n&prev=_t&hl=nl&ie=UTF-8&layout=2&eotf=1&sl=it&tl=en&u=http%3A%2F%2Fwww.ecv1.com%2Fhome.htm
  7. WhizzMan

    left hand threads on left hand wheel studs

    Formula 1 wheel nuts have a locking mechanism and are single centerpiece items. If the mechanism fails, inertia alone would make it possible for them to come undone. True, there are similarities to the multi-bolt setups for passenger cars, but I don't think it's a fair comparison.
  8. WhizzMan

    Pre-turbocharger methanol injection

    I think it would be quite a challenge to control the amount of methanol or the size of the droplets if you don't use a high pressure pump. At the very least, you'd need extra calculations in the ECU to correct for the pressure fluctuations.
  9. WhizzMan

    Pre-turbocharger methanol injection

    You are right about the temperature dependency of the vaporization. I got confused with delta T because you start with the same temperature in all cases, that of external air. What I also forgot is that the total amount of energy (heat) absorbed by the vaporization remains the same, regardless...
  10. WhizzMan

    Pre-turbocharger methanol injection

    Why would you want to inject at pre-compressor stage? The higher the temperature difference, the more efficient cooling will be. I can see a case where you'd argue to inject before any intercooler, to use that gain, but not before the compressor. In general, methanol is injected either...
  11. WhizzMan

    Effects of improper scrub radius on tire wear

    I've had a similar problem with a FWD drive car, McPherson style. Things improved with a little toe-out on the front. Personally, I'd be happy for 12K miles for a set of tires on that car.
  12. WhizzMan

    left hand threads on left hand wheel studs

    Maybe the Coriolis effect does work on bolts that aren't tightened enough? You still do see these still in practice on some modern vehicles, but most passenger cars tend to just use a normal thread these days. Wheel bolts on passenger cars (only thing I tinker on) that come off, usually are...
  13. WhizzMan

    Caliper placement re-birth

    I'm guessing the automatic made the whole gear/clutch/chain (see, no lever on the handlebar) drive line NA. The title on the photo sort of gives it away as well.
  14. WhizzMan

    Straight Line Reciprocating Engine...

    James Watt had to use a sun and planet technology because the crank and rod were patented by someone else. Watt in response came up with quite a few alternatives and patented those. After the patent on the crank and rod expired, everyone in steam engines went to that, until the turbine was...
  15. WhizzMan

    Dr. Paul Engine?

    Tires,wheels and brakes are bigger, mostly because the car is heavier. I compared the two top spec models to keep it fair and yes, the trend is that wheels are bigger and heavier. In fact, apart from this top model, the cars both have 254 disc brakes in front and drums in the back. The...
  16. WhizzMan

    Dr. Paul Engine?

    I drive Alfa Romeo, in Europe. The average alfa 33, considered a small midsized car here, weighed less than 900 kilo when first on the market. It could be bought with a 1.5 liter engine with over 100 bhp. Fuel economy was about 1 liter in 12 km. The replacement I own is a 145, 2 liter, 1250 kilo...
  17. WhizzMan

    Dr. Paul Engine?

    I commented on the blog, lets see what happens.
  18. WhizzMan

    No charge for 1st few minutes in the morning...

    Indeed, the charging light circuit is something to look at. Also, the MR2 is a mid-engined car that is notorious for water damage to the alternator and it's wiring. It seems that water coming from the roof and engine cover will drip on the alternator and it's surroundings, so corrosion to both...
  19. WhizzMan

    Rear seat pan design

    Regardless of design and safety requirements and regulations, you don't need the same material used in the entire body. Modern cars don't depend on welding as much as they used to. It is now very common to glue on panels that have a structural function, or even glue beams in some cases. This...
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