Why did the 1.8 engines have L-jet? |
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Why did the 1.8 engines have L-jet? |
technicalninja |
Jun 7 2024, 09:46 AM
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#61
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Senior Member Group: Members Posts: 1,948 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region |
The early use of CDI ignition was single strike (most of them) and was employed to increase ignition power at higher RPM. The baby coils we had back then suffered bigtime power loss above 5K rpm.
I have a funny story about cascading capacitors... My wife, who loves to take pictures had an "all in one" 35mm film camera (compact) that the "on" button stopped clicking and the camera would not open. Felt like a mechanical switch malfunction. We upgraded to digital, and the old camera sat for 6+ months (no film or 2 double A batteries in it). I mess with shit... So, I figured out how to get the "Chinese finger puzzle" case off of it and started "playing". I was messing with the on button and got into the circuitry for the flash. GAARRRZAP! It knocked me clean off the bar stool I was sitting on... Bit me HARD! My brain screamed Capacitor! OK, it's discharged now... I'm SAFE! Nope! Again, it knocks me off the stool! CASCADING CAPICITORS!!!! Now, I'm pretty gun shy about this camera... The THIRD time it knocks my dick in the dirt I take it over to the round file and trash that critter. 3 volts, no voltage for 6 months, and it still had the ability to light my fire at LEAST three times... I KNOW where the personal stun guns came from. I WILL NOT pick up a flash capable camera that has fallen into water with bare hands ever again... |
wonkipop |
Jun 7 2024, 04:30 PM
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#62
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Advanced Member Group: Members Posts: 4,658 Joined: 6-May 20 From: north antarctica Member No.: 24,231 Region Association: NineFourteenerVille |
Those are resistors, not capacitors. Capacitors are an "electron storage ballon" that can discharge the entire amount stored in a microsecond. A CDI ignition does not charge the coil slowly and then drop is like the original inductance ignition. Coils will create the secondary charge when the magnetic field inside the coil "changes rapidly". An inductance system charges slowly and drop to ground FAST creating the spark. Capacitive discharge does the opposite. Nail the coil with a huge amount of voltage and generates the spark on the CREATION of the magnetic field. An MSD "multi-spark discharge" hit the coil with cascading capacitors (multiple in series) and creates 3-6 individual sparks for each combustion event. The number of strikes decreases as RPM goes up. Most are down to a single strike at redline. I'm sure windforfun or Superhawk may have a better analogy/more info yes i didn't think our harmless 1.8s had it. but it sounds like porsche were out to get as much as they could from the last of the 2.0s in the 912E. ------- the other thing about those 76 2.0 914s is the 49 state cars would have been able to escape having cats and not complying with USEPA standards for 76 as well. which they appear to do as there are stickers in the doors saying non-catalyst. they would have been able to be repeats of the 75s. also 49 state did not have egr. theoretically they could have made 76 2.0 L for the whole model year (another 6 months) if they had production line space as the 49 state car for 76 would have been as per the 75 california car. it would only have been the california car that might have given them problems and needed to be perhaps a little like the 912E engine with L jet etc. i like your story of the deadly dead camera @technicalninja . (IMG:style_emoticons/default/biggrin.gif) |
Lo-Fi Version | Time is now: 28th October 2024 - 02:48 AM |
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