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Recent content by Retracnic

  1. Retracnic

    OEM Initial engine break-in procedure.

    Thanks for the responses. This is on par with what I expected. I had hoped for something a little more comprehensive on the part of the factory. Oh well. Regards
  2. Retracnic

    OEM Initial engine break-in procedure.

    Greetings, I would like to know the initial engine break-in procedure used by major automobile manufacturers or their suppliers. I am intimately aware of the procedures employed by race and performance engine builders. What I am looking for is what do the big guys (Toyota, GM, Honda etc) do to...
  3. Retracnic

    Diesel fuel/air ratio

    I don't get your question. The vast majority of diesel engines are not throttled, so a stoichiometric fuel mixture is never achieved during normal operation. Thus making the ideal AFR a moot point. Good Luck Bryan Carter
  4. Retracnic

    Emergency or extreme braking lights

    I, like many of you, have often thought that some sort of signaling device should be employed during emergency or panic braking situations. Specifically I think the signal should be triggered by a combination of depressing the brake pedal and the rate of deceleration as indicated by an...
  5. Retracnic

    Intake temps and IC piping questions

    The old "1% HP gain for every 10 degree drop in inlet temperature", is a decent rule of thumb. Like everything else automotive, your personal results may vary. Unfortunately there isn't a more reliable formula that can be calculated readily. There are simply too many other variables involved...
  6. Retracnic

    maximum piston speed?

    Along time ago the maximum attainable piston velocity was limited by the materials and manufacturing quality of the engine internals. For many decades OEM engine designers considered 3500 ft/min (17.8 m/s) to be the threshold. Think low-grade cast iron construction. With improved materials...
  7. Retracnic

    valve seat VS dyno output

    I have found this thread to fairly informative, but one question does spring to mind. How does valve included angle figure in relation to seat angle and lift? Just curious Bryan Carter
  8. Retracnic

    What turbo?

    Well you're free to try. The GT28RS is definitely well suited to this application, I just don't think it's up to the task of providing sufficient flow capacity for the power level you are trying to attain. Besides being well into the surge limit, the severe dropoff in compressor efficiency is...
  9. Retracnic

    What turbo?

    The GT28RS will not generally support 350 horsepower for this application. At 7500 RPM @20 PSI, you will need to flow approximately 38-40 lbs/min of air. The GT28RS has a maximum flow rate of roughly 35 lbs/min, which puts you a tad off the compressor map. Regards, Bryan Carter
  10. Retracnic

    Returning to the Moon...

    Though you all have brought up some interesting points, the topic has wandered from what I was originally asking. My father worked for over 30 years at Lockheed-Martin in the space engineering field, so I am quite aware of the various safety concerns. And though safety is of paramount...
  11. Retracnic

    Returning to the Moon...

    Actually, I think I didn't state my point clear enough. I fully understand the necessary requirements for insuring a margin of safety in man-rated spacecraft. When we first decided to go to the Moon in 1961 we literally did not posses the technology, materials, infrastructure or manufacturing...
  12. Retracnic

    Cart Engine RPM's

    The valve timing overlap required to sustain a given RPM in a turbocharged engine is dependent on several factors. Chief among these is the pressure differential between the exhaust and intake manifolds. If we look at a typical OEM setup, we're talking about exhaust manifold pressures in the...
  13. Retracnic

    Returning to the Moon...

    As I'm sure you are already aware, the Bush administration has tasked NASA with returning men to the Moon. Proposed future Lunar exploration is to commence sometime between 2015 and 2020. My question is do you think NASA will use "off the shelf" technology or push the limits with...
  14. Retracnic

    Shuttle fuel tanks

    Though the task of parking the 58,000 lb (dry weight assuming Super Lightweight model) shuttle external tank on low earth orbit is quite achievable, I don't think it's quite the economic windfall that some do. A good resource you might want to check out is at...
  15. Retracnic

    FWD posi trac with a Wheelie Bar

    The steering problem with traction bars (wheelie bars) on an FWD car do not come into play until the big end of the track (usually past about 800 feet or so). As we travel down the track, aerodynamic forces will tend to lift the vehicle. Since traction bars effectively lengthen wheel base, but...

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