MS3 Stock Boost Pressure?

hanzo040107

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07 Mazda MS3 GT Black Mica
I was searching the net for specs for the MS3, I can't seem to find one that says the stock boost pressure. I found max boost pressure of 15.6 PSI. If anyone knows it, can you post it here or provide a link to somewhere that shows it. Thanks.
 
its like 11-12 psi in 1st and 2nd gear and around 15.5 in all the rest. BTW even in stock form the ms3 will spike up to around 20psi in third then settle down to 15 or so. Get a boost controller and you can hit 17-18psi in everygear!!
 
My car hit a max of 13psi and fell off to 10psi. Maybe 15psi spikes in 5th. Must me my altitude. 2700ft.
 
i have never experienced this.

mine did this everytime i shifted into 3rd gear while driving it hard with just boost gauge and deleted 2nd cat, maybe the deleted 2nd cat had somthing to do with it, its very comon if you search ms3 boost spike you will see that many people experince a 19-20 psi spike even when the car is stock.
 
i have never experienced this.

also i bet that your using the small crappy nylon line for your boost gauge, if so you will get a very slow responding boost reading, i would upgrade to a regular rubber or silicane vacum line for your boost gauge so that you can actually see the true boost reading.
 
Cool, thanks. I guess that 15.6 I saw was right, thought it seemed a bit too high though. Thats always the question I'd get, how much boost does it run? I'd always have to say I didn't know & give out HP & Torque specs. :)
 
my car never held 15.6 either. Maybe for like a second or two. It usually held 12-14 which fell to 10 by 6k
 
I switched over to to better vac line after running the shiz they give you, and the guage reacts 100x better.
 
I run the supplied line and i dont beleive there is anything wrong with it, i hold 16 all day with no noticable spikes or poor reaction time. Just lucky i guess- touch wood (rubs his head)
 
Here is a current log of a WOT run in gears 1-3.

I spike to 14 psi in 1st, 17.3 in 2nd, and 18 in 3rd @ 4680 RPM. In 3rd, I'm down to 11.2 psi by 6K RPMs. At 6500 RPM I'm down to 6.1 psi.

Now its a different story if I start off say in 4th gear at a low RPM and then mash it. In the 2nd log, I spike to 20.6 psi at 3500 RPM and hold about 15.8 psi until 4650 RPM.
 

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This is why cars with turbos make me pull my hair out. I like consistent power. I love turbocharged cars but I don't think I could stand it if my neighbor and I bough the same MS3 and his stock boost was higher than mine. I know that there are a lot of variables that go with forced induction but dang! ranges between 13-16psi?
 
This is what it does, it actualy creeps up to 17 in 5th and 6th then settles which i had not noticed before.



 
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This is why cars with turbos make me pull my hair out. I like consistent power. I love turbocharged cars but I don't think I could stand it if my neighbor and I bough the same MS3 and his stock boost was higher than mine. I know that there are a lot of variables that go with forced induction but dang! ranges between 13-16psi?

I bet the variences between 2 different MS3's is more due to the location, weather, altitude etc.

I have compared my MS3 with 2 other people and in my area the mS3's are consistant.

someone up north with colder weather will probably get more/less boost than someone in the south.

i know for my Other turbo car, the boost controller varies due to weather, colder i get more boost, hotter weather gives me less boost for the same boost setting. about a month ago i popped a HG on my SVO due to the weather change in dallas. one month it was nice and warm, one month later when i came home it was cold and i over boost to 34ish psi or so. it was set on 25 psi so i got a hell of a jump. changed the HG and retuned the MBC and its all good now.

but of course this is just my theory, not proven by any means.
 
This is what it does, it actualy creeps up to 17 in 5th and 6th then settles which i had not noticed before.

Nice set up by the way!

For reference I have the Prosport E-boost gauge.

Loading up the motor in 5th and 6th (never good) that is where your crazy spike is coming from.

I had a similar issue while I was using the supplied clear hose they give you with the gauge kit. I just recently trashed it and used a 1/4 in rubber vac (im not saying this is your problem im just saying that it helped me!) line and under proper load the gauge does not spike or bounce or jump At WOT it runs right up to 16 and holds true until the Great And Powerful OZ shuts her down at 5500 rpm. Man I can’t wait till my Fuel pump gets here (yippy)...

I’m sure you checked but incase you didn’t take a look at the install and make sure you have no crazy coils, kinks or pinches in the vac line.

Maybe you got a crazy ass freak motor.
 
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