HP Tuners GEN 5 Oil Pressure (HIGH PSI Enable)

[LSCALADE]

For those with HP Tuners Access on the GEN 5 in my case L83 engine the oil pump is a 2 stage similar to what Stellantis has been using on the 3.6L and the 5.7L.

Basically it runs at reduced load thus making between 20-40psi and that is what you see on the gauges shown. Regardless of WOT mine would never go over 45psi.

In HP tuners you can go into the SYSTEM > VARIABLE OIL PUMP > Under Pressure control my cal was set to 7000rpm, the engine never reaches that type of RPMs. After looking at a police PPV Tahoe calibration theirs was set to 3500rpm.

I set mine at 3200rpm and on first log, when you cross 3200 RPM the oil pump goes to high pressure mode and bumps the PSI to about 60. Once you are below 3000rpm it returns to low pressure mode and thus the Hysterisis is set to 200rpm. You can change that to something like 300 if you like but I think the sweet spot is 3000rpm.

I hope this helps anyone who may not have even known that this exists on these engines. This also makes me wonder if the 2021-up engines that have engine problems are caused due to this.

IMPROTANT NOTE! Do this high pressure turn on ONLY if you have DOD disabled. The high pressure may not play well with the collapsable lifters or the solenoids that feed the oil pressure.

 

[Marky Dissod]

For those with HPTuners Gen5 Access in my case L83 engine the oil pump is a 2 stage similar to what Stellantis has been using on the 3.6L and the 5.7L.
Basically it runs at reduced load thus making between 20-40psi and that is what you see on the gauges shown. Regardless of WOT mine would never go over 45psi.

Does that mean that GM effectively disabled your oil pumps' second/high pressure stage?

In HPTuners you can go into the SYSTEM > VARIABLE OIL PUMP > Under Pressure control my cal was set to 7000rpm, the engine never reaches that type of RpMs. After looking at a police PPV Tahoe calibration theirs was set to 3500RpM.

I set mine at 3200RpM and on first log, when you cross 3200RpM the oil pump goes to high pressure mode and bumps the PSI to about 60.
Once you are below 3000RpM it returns to low pressure mode and thus the Hysteresis is set to 200RpM.
You can change that to something like 300 if you like but I think the sweet spot is 3000RpM.

I'm not disagreeing for fun, but I'd consider going as low as 2600RpM with a Hysteresis of 250RpM, simply because my experience is that the vast majority of drivers spend the vast majority of time UNDER 2600RpM.

IMPORTANT NOTE! Do this high pressure turn on ONLY if you have DOD disabled.
The high pressure may not play well with the collapsible lifters or the solenoids that feed the oil pressure.[/QUOTE]Is Engine Half@$$ disabled in that Tahoe 9C1-PPV calibration, where the oil pump enables higher pressure at 3500RpM?

I hope this helps anyone who may not have even known that this exists on these engines.
This also makes me wonder if the 2021-up engines that have engine problems are caused due to this.

Definitely yes this definitely helps anyone with the good sense to get tuned.

 

[LSCALADE]

My thoughts on this given my drive cycle, I go easy on the throttle with normal accelaration and my RPMs stay down low maybe below 2500rpm, which low pressure is fine but I notice when I start getting into it I quickly get to 3000rpm and anything north of there is a lot of throttle maybe 75% so I chose this as a test number as its in the high engine load range for my driving cycle.

However, lower makes sense too as you can get it to trigger high pressure under high loads but low rpms and that should not hurt anything.

An important thing is that I tested it, and it works perfectly and I think everyone should enable this. The police Tahoe gets this setting from the factory, and it has identical calibrations to the civilian versions.

 

[Marky Dissod]

Before I go on let me be clear: arguing with you because I disagree with a detail, is not actually the same as arguing against you.

OK​

However, lower makes sense too as you can get it to trigger high pressure under high loads but low RpMs, and that should not hurt anything.

As a pessimist with a 'Murphy-ian' bias, and someone who happens to know that even 9C1-PPV Tahoes are subject to CAFE MpG test scoring*,
and thus SUSPECT that GM set the high pressure threshold at 3500RpM to preserve their CAFE test scores,
whereas lowering it would cost 1, maybe 2MpG, but would prepare the engine by turning on the high oil pressure a split second before the high RpM.
(You don't put the bulletproof vest on AFTER they start shooting; how soon before is up to you.)
That's why I'd turn it on at 2600RpM - if you're doing 2600RpM, you'll most likely be at 3000RpM very soon.

 

[Joseph Garcia]

I would be interested in knowing what the GM specs are for non-SUV vehicles, like Corvettes, with this 2 stage oil pump.

 

[WingsAA]

Keep in mind, it depends on the year. It's only later M/Y models that GM changed the calibration to 7000... I think mid '17, but definitely for '18 M/Y.
On my 2016 Yukon XL Denali (L86), the factory calibration is set at 3500. As well, the calibration I did on my sister's Suburban (L83), and that factory calibration was also set at 3500.