Georgia Fiero Club Forum
All Things Fiero => General Fiero Discussion => Topic started by: GTRS Fiero on August 05, 2018, 09:48:56 am
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Is it possible to have a digital EGR, and still have HEI?
Is DIS possible with a carb engine? I see no reason why not, but I've never seen such, and maybe the 30-year gap in technology would make this ill-advised. Of course, just because you can, doesn't mean you should.
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I think both scenarios would be technically possible. The question is why? You're wasting a great deal of available computer power.
Sort of like having laser sights on a musket.
Especially the EGR. If you're going all "primitive", with the HEI, it's probably a valid assumption that you don't have to pass any emissions testing.
Why would you even bother with EGR, at all?
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Well, I had someone tell me that DIS was one of my worst ideas yet. My understanding was that DIS is more precise than HEI, and therefore cleaner, that it comes with electronically variable timing, allowing more efficient engine operation, and that the ICM was less prone to failure.
Some people have a 454 carb V8 from back in the '70's. Maybe they want DIS or a digital EGR. I doubt any computers are equipped for such.
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Well, I had someone tell me that DIS was one of my worst ideas yet. My understanding was that DIS is more precise than HEI, and therefore cleaner, that it comes with electronically variable timing, allowing more efficient engine operation, and that the ICM was less prone to failure.
Some people have a 454 carb V8 from back in the '70's. Maybe they want DIS or a digital EGR. I doubt any computers are equipped for such.
Someone was just looking for something to criticize.
I would think that most - if not all - of what you said is true. HEI still uses a distributor. Even at it's best, it's still subject to all the afflictions of any mechanical device. Wear in the shaft or bearings, ICM failure. Carbon tracking on the rotor (I've got a good war story about that) or cap, burned plug wires, etc., bla, bla, bla.
DIS has NO moving parts. It does require electronic control, and must use the appropriate tables and values. The latest iteration of that is "coil on plug". Since the coil is mounted right over the plug, there are no high tension leads (aka spark plug wires). Everything is low voltage, right up to the coil pack.
Thinking about it, I think I have seen a DIS setup for a "carbed" LS motor.
Here ya' go.
https://www.chevyhardcore.com/tech-stories/engine/tech-carbureted-ls-engines-ignition-and-induction/
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I think Oreif had something like that.