TORQUERULES
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Some of us discussed in another thread that had the topic of LSPI (low speed pre-ignition) and the causes of this phenomenon come up because of a catastrophic engine failure that on the surface looks similar to an LSPI failure (though this is in no way confirmed and could just be coincidence). While this failure is very remote in as it is the only one reported so far in the 5g Ranger community, it is worth paying attention to.
LSPI is a phenomenon with many believed causes, but none of them seem to be the only cause so there are things that can be done to minimize the issue. I will post an article below about LSPI, but the reason for this post is one possible cause which is lugging under high load at a low rpm. It is advised to avoid this if you can, but our trucks, even with tunes (maybe especially with tunes since the torque production is even higher than stock by a wide margin so they lug easier), have a tendency to lug in the overdrive gears and hold these way too long at low rpm high load unless we force a downshift. Various things can happen here to cause LSPI. A manual downshift is a good strategy to use instead of a quick throttle stab because of the possible pressure spike that could cause LSPI. It would have been nice if Ford had not been so concerned with fuel mileage that they would have programmed the transmission to hold gears longer and downshift sooner. Sport mode is a good compromise, but its gear holding is often too aggressive for daily driving and fuel mileage. Honestly the mileage does not suffer if the engine is kept at or near 2000-2500rpm during normal cruise. A lower rear end ratio of a bout 4:30 would have been perfect, with a better shift strategy, but again that dreaded fuel mileage rating was more important...
So, I talked to Torrie at Unleashed Tuning and told him just what was occurring and what I needed (hold gears a little longer but not as aggressive as Sport, and downshift sooner to keep the engine in its cruise sweet spot. All to prevent lugging.). His tune already makes some effort to prevent this, but I thought more could be done. In true Torrie fashion he got back to me in a day with a tune that is about as perfect in Normal drive mode (which is the mode we are talking about here) as you can get. It is so good that I am hesitant to push things further since programming these A10s with all of their different strategies can be very complex and finicky. This is how it should have came from the factory.
So, if this is a concern and you have an Unleashed tune, then reach out to Torrie and ask about what he did for me. He will recognize the username.
If you do not have an Unleashed tune, then you can still talk to your tuner. Just be specific.
Article: Blog : Stratified Automotive Controls
LSPI is a phenomenon with many believed causes, but none of them seem to be the only cause so there are things that can be done to minimize the issue. I will post an article below about LSPI, but the reason for this post is one possible cause which is lugging under high load at a low rpm. It is advised to avoid this if you can, but our trucks, even with tunes (maybe especially with tunes since the torque production is even higher than stock by a wide margin so they lug easier), have a tendency to lug in the overdrive gears and hold these way too long at low rpm high load unless we force a downshift. Various things can happen here to cause LSPI. A manual downshift is a good strategy to use instead of a quick throttle stab because of the possible pressure spike that could cause LSPI. It would have been nice if Ford had not been so concerned with fuel mileage that they would have programmed the transmission to hold gears longer and downshift sooner. Sport mode is a good compromise, but its gear holding is often too aggressive for daily driving and fuel mileage. Honestly the mileage does not suffer if the engine is kept at or near 2000-2500rpm during normal cruise. A lower rear end ratio of a bout 4:30 would have been perfect, with a better shift strategy, but again that dreaded fuel mileage rating was more important...
So, I talked to Torrie at Unleashed Tuning and told him just what was occurring and what I needed (hold gears a little longer but not as aggressive as Sport, and downshift sooner to keep the engine in its cruise sweet spot. All to prevent lugging.). His tune already makes some effort to prevent this, but I thought more could be done. In true Torrie fashion he got back to me in a day with a tune that is about as perfect in Normal drive mode (which is the mode we are talking about here) as you can get. It is so good that I am hesitant to push things further since programming these A10s with all of their different strategies can be very complex and finicky. This is how it should have came from the factory.
So, if this is a concern and you have an Unleashed tune, then reach out to Torrie and ask about what he did for me. He will recognize the username.
If you do not have an Unleashed tune, then you can still talk to your tuner. Just be specific.
Article: Blog : Stratified Automotive Controls
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