abeans":dq4mabgd said:
Not too worried. EGR is closed during wot. Parts car made it 240k with a egr delete, and we got some decent fuel in Michigan. ...and if i don’t end up wanting to jump off a bridge at the end of this project, might treat the car to some Link ECU.
Just saw this response. I find it an interesting conclusion that an EGR system can be plugged/deleted without consequence. This response contradicts the conclusion.
Yes, by design, an EGR valve is closed when the engine is cold, is idling, or is under wide open throttle. The ECU mapping is designed to retard timing under wide open throttle to compensate for the otherwise normal benefit of EGR into the intake to reduce detonation. So removing EGR has no consequence on an engine when under wide open throttle. That is understood.
Detonation also can happen in an engine at less than wide open throttle. In an engine designed for EGR, the ECU doesn't retard timing as much as an engine without EGR. Knock sensors will help retarding ignition timing further, true. But understand the ECU ignition timing map is based on EGR control and knock sensor feedback. Now, take away EGR that is normally present in this case, and the knock sensor detects knock, the ECU will retard timing only to the extent it is mapped to do (which incorporates the benefits of EGR being partly open). Delete or block EGR, the timing will not retard sufficiently to eliminate knock - so it will be present. Will it be sufficient to damage the engine? I'm not sure, are you? And is that a risk you want to take?
Remap the ECU ignition timing to handle ignition timing as if not EGR was designed to be present, and you would be OK. But in this case, while you are protecting your engine, you really don't get any more torque/power than with an EGR system and an ECU mapped to work with an EGR. Retarding timing more due to the lack of EGR has negative performance results.
Or, block/delete EGR without remapping the ECU ignition timing and live with the added risk. Up to the user. But need to know you are adding risk.
My last response on this topic.