That boost patter looks about like mine,,I dont feel so bad now..thanks 4 the video.. I can spike to 16-17 in sixth on the heyway but boost levels look the same..I get 20 hg vacuum at idle and 22-25ish on decel..Looks like you where at almost 30..I need to get better lines as the advance auto black vacuum lines could be crushing/pinching under vacumm throwing off my gauge..I have a modded airbox so I get a touch more spike that u though..
What kind of Boost Levels are MS3 owners seeing?
- Thread starter redms3gt
- Start date
Aaron@Realtune
Member
That is pretty funny that you dropped the camera. (shocked)
Thanks for the video tho!
Thanks for the video tho!
Aaron@Realtune
Member
Looks like I will have my hands on an MS3 very shortly. A long time friend of my partners is buying one soon. Keep a look out for some insight from us soon (glare)
quiet desperado
Member
- :
- Mazdaspeed3
Just confirming that boost is down in 3rd to 12 psi max
I was playing with my boost gauge yesterday and I noticed that when going up an incline in 5th the boost was holding nicely at 16 psi. No spiking and settling down, just a nice solid 16 psi while the engine was under load. I then did several runs in 3rd-6th, going up hills steep enough to keep engine under load for several seconds each time. 4th-6th will hold 16 psi when going up an incline without any problem. It takes a pretty steep hill to test 3rd, but when I found one it showed that it will hold no more than 12 psi max. Whichever article it was that said boost was limited in 1st-3rd was right.
Also, wet pavement is not your drivetrain's friend under hard acceleration in 3rd. I won't be repeating this experiment on wet pavement again due to the wheel hop and other incidences of unpleasantness I experienced. By "unpleasantness", I mean it in the same way that a South Carolinian I used to know used the term to refer to the Civil War. I think anyone who unleashes substantially more power out of this engine will definitely need to replace the rear engine mount and check all the other mounts regularly. I should add, though, that torque steer was never a problem! But Mazda should have gotten the word out to all the car mag journalists that 3rd is in fact limited. Instead, I think it saw this interesting fact in just the one review, in an Aussie mag. Don't even remember which one.
I was playing with my boost gauge yesterday and I noticed that when going up an incline in 5th the boost was holding nicely at 16 psi. No spiking and settling down, just a nice solid 16 psi while the engine was under load. I then did several runs in 3rd-6th, going up hills steep enough to keep engine under load for several seconds each time. 4th-6th will hold 16 psi when going up an incline without any problem. It takes a pretty steep hill to test 3rd, but when I found one it showed that it will hold no more than 12 psi max. Whichever article it was that said boost was limited in 1st-3rd was right.
Also, wet pavement is not your drivetrain's friend under hard acceleration in 3rd. I won't be repeating this experiment on wet pavement again due to the wheel hop and other incidences of unpleasantness I experienced. By "unpleasantness", I mean it in the same way that a South Carolinian I used to know used the term to refer to the Civil War. I think anyone who unleashes substantially more power out of this engine will definitely need to replace the rear engine mount and check all the other mounts regularly. I should add, though, that torque steer was never a problem! But Mazda should have gotten the word out to all the car mag journalists that 3rd is in fact limited. Instead, I think it saw this interesting fact in just the one review, in an Aussie mag. Don't even remember which one.
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I posted about this somewhere else on this board but it also seems relevant here.
I bought my MS3 on Halloween. Sometimes it seemed like 3rd was flat. Like I wasn't getting the power I should have. Thought it was just me, since I had never driven anything with a turbo before. Well now I know it wasn't just me.
I have 1900 miles on it and Tuesday the CEL came on.
Friday morning when I was scheduled to take her to the dealer the CEL was off. I took her in anyway.
They ran their diagnostics and found that the Intake Manifold Runner Control Valve was the problem. He didn't tell me exactly what it does but from what I've read it is supposed to stay closed at low RPM. The computer thinks it stays open when it doesn't. So to fix it They elongate the hole that the screw fits in to that holds the valve on to the intake. This makes the springs tighter on the valve. That's how they explained it to me anyway.
They called Engineering and had it fixed in 1 hour 30 min. They are keeping the ticket open in case the light comes on again. He gave me a 70% chance that it won't come back on. He also said that he had to do the same thing to a CX-7 a while ago.
So back to my point: 3rd gear no longer feels restricted!! I imagine that this problem will effect most if not all MS3's. It's a design flaw.
Sorry if I couldn't explain it real well but I feel this is one if not the problem people are having with their MS3's just not feeling like they are at their fullest potential.
I bought my MS3 on Halloween. Sometimes it seemed like 3rd was flat. Like I wasn't getting the power I should have. Thought it was just me, since I had never driven anything with a turbo before. Well now I know it wasn't just me.
I have 1900 miles on it and Tuesday the CEL came on.
Friday morning when I was scheduled to take her to the dealer the CEL was off. I took her in anyway.
They ran their diagnostics and found that the Intake Manifold Runner Control Valve was the problem. He didn't tell me exactly what it does but from what I've read it is supposed to stay closed at low RPM. The computer thinks it stays open when it doesn't. So to fix it They elongate the hole that the screw fits in to that holds the valve on to the intake. This makes the springs tighter on the valve. That's how they explained it to me anyway.
They called Engineering and had it fixed in 1 hour 30 min. They are keeping the ticket open in case the light comes on again. He gave me a 70% chance that it won't come back on. He also said that he had to do the same thing to a CX-7 a while ago.
So back to my point: 3rd gear no longer feels restricted!! I imagine that this problem will effect most if not all MS3's. It's a design flaw.
Sorry if I couldn't explain it real well but I feel this is one if not the problem people are having with their MS3's just not feeling like they are at their fullest potential.
It would be interesting to know how many cars have the PZEV option. It is required in California, Massachusetts, Maine, New York and Vermont. However it may be installed on other cars too. I'll bet it has different controls and may limit the boost in 3rd where the non-PZEV version may not. Just a thought. How do you know if you have this "option"?
quiet desperado
Member
- :
- Mazdaspeed3
Vixen said:
I think I've read something about this somewhere. Interesting, but can you get a boost reading post-fix to see if it's pushing more than 12 psi? You want a gauge anyway don't you? I can provide detailed instructions on the install if you pull the trigger.
all gears...http://www.driveclean.ca.gov/en/gv/vsearch/cleansearch_result.asp?vehicletypeid=16matsuda said:
Scroll down to the Mazda 3.
http://www.carsdirect.com/build/options?zipcode=94062&acode=USB70MAC221B0&restore=false
Check under "Other Options"
I just measured my boost pressure using Auterra Dyno-Scan. Here are my first results:
Temp: 34 deg. F
Barometric Pressure: 29.6 in Hg(from Car PCM), 30.43 (from www.nws.noaa.gov)
Humidity: 90%
Altitude: 535 Feet
Drag Start (shift at 6000 RPM in each gear):
1st gear: 9.578 psi (peak)
2nd gear: 15.570 psi (peak)
3rd gear: 14.391 psi (peak)
4th gear: 16.699 psi (peak)
Punched in each gear from 3000 RPM to 6000 RPM:
1st gear: 9.725 psi (peak)
2nd gear: 13.212 psi (peak)
3rd gear: 13.654 psi (peak)
4th gear: did not measure cause radar detector went off!
I also have power/torque curves in each gear, but here are the peaks:
Note: these are taken from the rubber on the road, not at the crankshaft, so they will look wierd.
1st gear: 127.1 HP @ 5000 (peak) / 139.5 Ft-Lbs @ 4600 (peak)
2nd gear: 184.9 HP @ 5300 (peak) / 184.3 Ft-Lbs @ 3600 (peak)
3rd gear: 197.6 HP @ 5500 (peak) / 211.9 Ft-Lbs @ 3400 (peak)
4th gear: 226.2 HP @ 5100 (peak) / 244.4 Ft-Lbs @ 4500 (peak)
I will try more runs (especially 5th and 6th gear) when I get more time. I did an initial acceleration run as a sanity check on the power ratings and got 6.8 seconds 0-60, but I missed 2nd gear sync.
Temp: 34 deg. F
Barometric Pressure: 29.6 in Hg(from Car PCM), 30.43 (from www.nws.noaa.gov)
Humidity: 90%
Altitude: 535 Feet
Drag Start (shift at 6000 RPM in each gear):
1st gear: 9.578 psi (peak)
2nd gear: 15.570 psi (peak)
3rd gear: 14.391 psi (peak)
4th gear: 16.699 psi (peak)
Punched in each gear from 3000 RPM to 6000 RPM:
1st gear: 9.725 psi (peak)
2nd gear: 13.212 psi (peak)
3rd gear: 13.654 psi (peak)
4th gear: did not measure cause radar detector went off!
I also have power/torque curves in each gear, but here are the peaks:
Note: these are taken from the rubber on the road, not at the crankshaft, so they will look wierd.
1st gear: 127.1 HP @ 5000 (peak) / 139.5 Ft-Lbs @ 4600 (peak)
2nd gear: 184.9 HP @ 5300 (peak) / 184.3 Ft-Lbs @ 3600 (peak)
3rd gear: 197.6 HP @ 5500 (peak) / 211.9 Ft-Lbs @ 3400 (peak)
4th gear: 226.2 HP @ 5100 (peak) / 244.4 Ft-Lbs @ 4500 (peak)
I will try more runs (especially 5th and 6th gear) when I get more time. I did an initial acceleration run as a sanity check on the power ratings and got 6.8 seconds 0-60, but I missed 2nd gear sync.
desperado-c
Member
- :
- Mazdaspeed3
Speedy3 said:
That's interesting data, but I think the 4th-6th gear roll on boost is the one we all want to see. Also, since those figures are higher than most of us have seen, I assume that "peak" is equal to "spike". Can your data logger show what psi the boost settles at after the spike?
desperado-c
Member
- :
- Mazdaspeed3
Speedy3 said:
Fantastico!
