Please analyze by boost gauge data (VIDS)

[DRKNYTE]

So I recently installed a DEFI Imperial 60MM Boost Gauge and DEFI Controller in my vent. I have a few questions....

1. Does it look like I`m leaking boost?

2. I get that all the readings on the boost gauge above 0 is boost pressure, but what are the readings below 0? (The opposite of boost would be vacuum right?)

3. I`ve seen as low as 10 psi on some 1st, 2nd, 3rd, and 4th gear pulls and have seen them as high as 19 psi. Is that range normal?

4. What causes such variations in boost pressure?

5. What should a typical mazdaspeed 3 be boosting?

6. What will give me more consistent boost pressure? (Aftermarket BPV i.e. HKS SSQ or an AP or both)


Please analyze these vids and tell me what you think (All pulls were done with traction control off, stock bypass valve, CP-E CAI and TIP, CP-E RMM, Engals ETD)

First recording: http://www.youtube.com/watch?v=fF4FlXoGYA0
This is 2nd, 3rd, and 4th gear pulls.

Second recording: http://www.youtube.com/watch?v=SZCkWzF1-FU
This is 1st, 2nd, and 3rd gear pulls.

Third recording: http://www.youtube.com/watch?v=pOlRzd8A7KA
This is 2nd, 3rd, and 4th gear pulls.

Fourth recording: http://www.youtube.com/watch?v=AQNanI_B97U
This is the highest boost level I`ve reached since the gauge was installed.


Thanks guys!!

P.S. Sorry for the side ways videos

 

[mr_mazda329]

Well.. looks like your BPV is leaking pretty bad. I just discovered that my Forge BPV was leaking and i was only holding like 13psi. I put my stocker back on and it hold 14.5 psi

 

[DRKNYTE]

Can you explain why you think it's leaking... I just want to see if I`m seeing what your seeing when looking at the boost gauge.

 

[mr_mazda329]

Can you explain why you think it's leaking... I just want to see if I`m seeing what your seeing when looking at the boost gauge.

the stockers are notorious for leaking. A leaking valve will spike, and then taper off the boost slowly. plus... only 12 or so psi... thats no good.

 

[hugador]

Man your car is quite with those mods. I'm starting to think that factory bpv don't leak none of them do they're just made crap. A stock bpv may not handle an upgraded Intake or TIP. You should be around 15 to 14 psi. Could be the gauge not working properly. Nice gauge by the way. What ever the cause may be you should get an aftermarket bpv. May I suggest you the Turbosmart Bypass Valve Kit just install it with standard spring and done.

 

[DRKNYTE]

I`m not actually driving, the control unit for DEFI gauges records data so I made a recording of the recording

Can I get some answers to some of my other questions please.

Thanks!

 

[DRKNYTE]

Come on fellas, were are the smarty pants... I have questions and need answers....

 

[Silver Ecstasy]

To be completely honest, I did not have a boost gauge when I was stock.

I installed a MSCAI then eventually got the Dashhawk and hardly watched boost religiously. Then I installed the Forge BPV and noticed I'd almost never hold 15psi ever. I'd maybe briefly touch 15psi then it'd taper down to 12. I've noticed this in 3rd, 4th, and 5th. 6th gear will actually be the most consistent gauge for high 14's PSI.

I removed the Forge and installed my stock BPV. The car seemed to pull stronger but my Dashhawk was saying the same inconsistent #'s.

SO...my post may be total fail (in helping..) but i've experienced the same exact thing. I got tired of obsessing over Boost, or the lack there of (with my mods), so I decided to remove the BPV and go back to stock.

FWIW, i've been in other MS3's that have BPV's and Intakes and hold 15psi and 16psi NO PROBLEM and pull like ***** apes. Mine makes absolutely no sense and I've gotten tired of analyzing it.

 

[coyfish]

^^^^^ weird. Not saying you did but many people don't use the correct spring with thier forgies. Or have other boost leaks not associated with the bpv.

Anyhow I spike up around 20 and hold anywhere from 16.5-19 depending on how my car is feeling that day / conditions. Depends on many factors.

The reading below zero is vacuum pressure which is normal unless you step on the gas and hit boost. During DD I don't go into boost. When you idle it should be around -19 to -21.

If your holding 10 psi in 3rd gear at WOT then you have a problem. Start by checking boost leaks.

Variations in boost pressure in this car are pretty common but within a certain limit. They are due to temperatures, humidity, altitude, how your car is feeling that day . . .


Stock boost in a speed 6 is 15.6 psi I think I read. Would be the same in a 3 aside from the 1st / 2nd gear limit.


Buy a bpv. The new turbosmarts are nice. Forges are popular and cheap. The new forges apparently dont make the "ping" that some people dislike. Down the road I think its a good investment and if you dont like it . . . sell it. You will get most of your money back. HKS's are nice and you can run VTA if you feel like it. Granted thats not advised but if I had one I would play with it. Its pretty expensive though.

As for tunes. The AP is a good way to manage boost as well. Many people have had success tuning at a certain boost level such as 18. Others still have trouble.

 

[hugador]

^ there you go

 

[Silver Ecstasy]

The most consistent boost I had was when I had borrowed a Cobb AP for 2 weeks. I'd hit 19psi and HOLD it in 6th gear! It didn't feel..safe. After I uninstalled, I started getting regular KR when the car was cold and in part throttle boost. Since then, i've stopped using 6th gear in cruising on the highway until it's further warmed up, to reduce load.

I've checked the inlet (actually had a PG inlet installed and removed it), boost tubes, my intake. I've checked everything and all the connections are good and tight. I may end up re-installing my Forge BPV (always ran blue spring, no shims), but we're rapidly approaching colder weather and I won't have the opportunity to "test" out WOT boost runs.

My car definitely seems to have it's strong and weak days, but like i've said, i've stopped obsessing over the #'s. I will say that even though I didn't consistently see 15psi with the Forge, I wouldn't lose boost after 5500 rpm like I do with the stock BPV.

 

[DRKNYTE]

^^^^^ weird. Not saying you did but many people don't use the correct spring with thier forgies. Or have other boost leaks not associated with the bpv.

Anyhow I spike up around 20 and hold anywhere from 16.5-19 depending on how my car is feeling that day / conditions. Depends on many factors.

The reading below zero is vacuum pressure which is normal unless you step on the gas and hit boost. During DD I don't go into boost. When you idle it should be around -19 to -21.

If your holding 10 psi in 3rd gear at WOT then you have a problem. Start by checking boost leaks.

Variations in boost pressure in this car are pretty common but within a certain limit. They are due to temperatures, humidity, altitude, how your car is feeling that day . . .


Stock boost in a speed 6 is 15.6 psi I think I read. Would be the same in a 3 aside from the 1st / 2nd gear limit.


Buy a bpv. The new turbosmarts are nice. Forges are popular and cheap. The new forges apparently dont make the "ping" that some people dislike. Down the road I think its a good investment and if you dont like it . . . sell it. You will get most of your money back. HKS's are nice and you can run VTA if you feel like it. Granted thats not advised but if I had one I would play with it. Its pretty expensive though.

As for tunes. The AP is a good way to manage boost as well. Many people have had success tuning at a certain boost level such as 18. Others still have trouble.

That's what I`m talken about coyfish... Thank you

How about the waste gate....it controls boost right? Can you get a better waste gate that can regulate boost more effeciantly?

See I come from high reving N/A Honda Motors, and since I switched over to the turbo side of things, I`ve noticed that the amount of power these cars produce is very inconsistant. In my Honda I new exactly what I would get when I punch it, very consistant power, it never suprised me. With MZR it still takes me by surprise sometimes. So anyway I`m just trying to figure out how to better control boost.

I got the boost gauge before the BPV to see if going with an after market BPV really makes a differance. I`ve pretty much made up my mind with the HKS SSQ w/ the CP-E adapter. I`m just waiting on funds now.

I think I`ll go through all the boost related tubes and hoses to make sure everything is good and tight.

Just so I`m clear on that topic it would be the boost tubes on the intercooler to turbo and intercooler to throttle body, TIP to turbo and TIP to CAI clamps, recerculation hose from TIP to BPV, and what else?

Thanks!

 

[Silver Ecstasy]

Well, that's the thing. The Wastegate is (in my imagination) over-protective. It'll let a spike slip by but it quickly reels Boost back in.

I've heard mixed reviews on the HKS. I've heard more consistently happy reviews with the Forge.

 

[coyfish]

I wouldn't mess with the wastegate. That would be better for people who are overboosting and need help keeping it in line.

Welcoem to the world of forced induction turbo's. This car is just like a chick. Never know whats going to happen or how shes feeling. Part of it is the intercooler. With my TMIC my car became "more" consistant.

Sounds like your good on checking for leaks. Also check that your T (for the boost gauge) is nice and snug.

 

[DRKNYTE]

Copy that! Thanks!