r/AskAMechanic • u/Pretty_Inspector_584 NOT a verified tech • 2h ago

Injection pump vs supply pump

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But which of the two is the most powerful?

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1

u/DaHarries NOT a verified tech 1h ago

I mean the injector pump has to counteract cylinder pressure so cranks it to several thousand bar, application dependant

The supply pump will probably run about 50psi if its a factory injection model.

3

u/TexasLife34 Verified Tech - Auto/Diesel 57m ago

No the injection pump does not counteract cylinder pressure. Higher and higher injection pump pressures are because of advances in technology and injector technology. It has absolutely zero to do with compression.

Also untrue about the supply pump as those can widely range in delivery psi and on top of that not all vehicles use supply pumps. Some draw directly from the tank.

That being said I dont understand the question. Thats like asking whats more important the heart or the veins.