22psi Stock???

[wolfgang82]

I want to preface by saying my car is running great with no issues... That being said, my car is a 2018 Si coupe with only one modification being a MAPerformance CAI. I just went out for a drive and I hit 22 psi on the gage. It’s 56 degrees where I am and this is the first time I’ve ever seen 22psi, but I’ve normally seen 20 and 21 psi several times. This seems uncommon, any thoughts on why? Is my gage just wrong?

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[Drake]

Did you buy your Si used?

 

[gtman]

If you bought it used, my guess is the previous owner sold/traded it with a tune on it. No way you'd see 20-22 psi on a stock Si. Most you'd see stock is probably 17-18 psi max.

 

[360glitch]

I would be curious to see what your fuel trims are.

 

[wolfgang82]

If you bought it used, my guess is the previous owner sold/traded it with a tune on it. No way you'd see 20-22 psi on a stock Si. Most you'd see stock is probably 17-18 psi max.

I bought it used in January, there were no previous mods to the car everything on it was kept stock. I know most people see the 17-18 are in Cali where it’s regularly hot and heat soak easy, so my guess is temperature is a big part of it.

 

[wolfgang82]

I would be curious to see what your fuel trims are.

I get 93 octane and average 30mpg.

 

[wolfgang82]

I get 93 octane and average 30mpg.

Also don’t know exact trims

 

[Drake]

I bought it used in January, there were no previous mods to the car everything on it was kept stock. I know most people see the 17-18 are in Cali where it’s regularly hot and heat soak easy, so my guess is temperature is a big part of it.

An ECU reflash is a mod invisible to all those without the right equipment to detect a reflash

 

[wolfgang82]

An ECU reflash is a mod invisible to all those without the right equipment to detect a reflash

? I haven’t considered that, ecu flashes seem atypical for these cars but I guess it’s still possible. What equipment is needed to detect one?

 

[360glitch]

? I haven’t considered that, ecu flashes seem atypical for these cars but I guess it’s still possible. What equipment is needed to detect one?

Actually an ECU flash is probably the most common modifications for these cars. If done properly, it's not a bad thing. The best way I know to check would be to record a datalog. Of course to do this, you would need to have an ECU flashing device. (borrowing would be fine for testing purposes)

If you are running an MAP intake you are fortunate if it is has a matching tune. Those intakes typically run a bit on the lean side without a proper MAF scale. However if you put the MAP intake on the car yourself it is unlikely that any previous tune would match it.

 

[wolfgang82]

Actually an ECU flash is probably the most common modifications for these cars. If done properly, it's not a bad thing. The best way I know to check would be to record a datalog. Of course to do this, you would need to have an ECU flashing device. (borrowing would be fine for testing purposes)

If you are running an MAP intake you are fortunate if it is has a matching tune. Those intakes typically run a bit on the lean side without a proper MAF scale. However if you put the MAP intake on the car yourself it is unlikely that any previous tune would match it.

Well I actually have been planning on ordering a Ktuner this week from phearable so maybe I can datalog soon

 

[gtman]

I bought it used in January, there were no previous mods to the car everything on it was kept stock. I know most people see the 17-18 are in Cali where it’s regularly hot and heat soak easy, so my guess is temperature is a big part of it.

Temperature plays a part. Elevation plays a part. But mostly, you simply won't be seeing 22 psi untuned, ever. Technically, Honda has the tune peaking at 20.3 psi but I honestly haven't heard of anyone with a stock Si seeing that regularly. Or even close to that.

I have a non-Si turbo. Honda says it's 16.5 psi. Reality is that untuned, the max I saw was 13-14 psi under rare and perfect conditions and no, I don't live in California but in a state that sees below freezing temps often.

And 360glitch is right about the MAPerformance intake. Derek Robinson said it's the worst intake in terms of getting the MAF scale correct to keep fuel trims where they should be.

 

[ValkenDnB]

I'm completely stock here in California and I never see above 17-18 even when it was winter (boost season). 40F-50F weather. Your car has a tune on it for sure.

 

[danfg2]

You bought a car that is tuned.

 

[wolfgang82]

Update, not that anyone necessarily cares, my car did not have a tune on it. As stated I have a MAP CAI on my car, which has an improper MAF housing design. I am going to be ordering the PRL with the race MAF and Phearable 1.5R tune to go with it.

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