Boost Targets Q

[spd frk]

Just wanted to see other Canada members with boost guages, how do your boost patterns look in the cold weather. My car is stock right now except for an RPMC inlet. I put in an autometer boost guage in December.

I noticed I have not yet run a steady 15.6psi. I imagine because of the cold weather the ECU reduces the boost target.

Today is 2C in Toronto, in 4th gear I get a spike to 19psi, then it drops to 15 and holds for a bit then about 4000rpm it starts dropping off to 12psi and holds there (yes I know this is base wastegate pressue).

A different day it was -19C and I spiked to 14psi, then it dropped off to a steady 9psi allthrough 4th gear.

Is this typical behaviour for our weather. I don't imagine I have a 3psi boost leak.

J

[alhope34]

With the Cobb AP stage 2+ 93 v103 map I peak 22.8psi, hold 18.9psi till 6000rpm and it drops to 16.5psi by 6700rpm. It doesn't matter what the temperature is it will still hold this, but below -8 my car gets fuel cut like crazy in 4th and up. Also, upgrading the stock BPV will help a lot with holding proper boost. The stock one leaks at higher psi and rpm. I got the Forge. Its cheap and works well.

[spd frk]

I already run the HKS SSQV, and RPMC inlet pipe. No other mods yet. I find it is bizarre boost behaviour, but like I said I can't imagine I have such a hueg boost leak as the car seems to run 100% normal, and I get great mileage.

[Mazda3X2]

I just installed my gauge a couple days ago so I haven't seen all that much yet. Here's what I have noticed.

Car is running stock right now as far as engine, intake and exhaust are concerned.

I am only peaking at about 15psi, holding at around 13psi and then dropping to 12ish by around 6k.

I thought I would see a little more boost than this to tell you the truth. With the CAI will that make much difference?

[spd frk]

Anyone is free to correct me. But I think the stock electronic boost control solenoid is set to manage wastegate duty cycle to maintain 15.6PSI at some standard temperature and pressure. Maybe standard air pressure of 14.7psi and 80F or something. Since it is so much colder outside right now (in TO anyways) this map is actually reducing boost to a point where we see less than 15.6psi due to the cooler temps. I imagine when it gets back to summer and temps are 20+C, then the psi will be right on.

[alhope34]

Well, I never had a boost guage before I got the AP so I have no idea what my stock tune was like. But, I also has the MS CAI (in SRI mode with air straightener for the winter), RPMC inlet pipe, Forge BPV, TurboXS DP, and CP-e cat-back. I had all these parts before I got the AP, so when I tune the car back to stock for my next oil change I will see what kind of boost patterns it gets.

[5_Alive]

my car has been an absolute monster lately.. pulling all the way past 6500rpm in every gear, and pulling hard..
all i have is an injen cai, greddy type-s and the factory resonators removed.. the car also has 49k on it now, so its in its prime..

[alhope34]

I'm just at 50,480km right now on my 08 after my drive home from MTL. I thought about 50k kms is where the engine starts the real wear and tear? lol.

[5_Alive]

^lol I hope not hahaha! If that is the case, how long before our cars go BOOM BOOM?!

[Pilzz]

^lol I hope not hahaha! If that is the case, how long before our cars go BOOM BOOM?!

LOL my car went BOOM @ 68K. Got a new motor tho!!!!