Any mechanical gauges scaled in ABS vs Vac + Boost?
#1
Retired Mech Design Engr
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Any mechanical gauges scaled in ABS vs Vac + Boost?
For no particular reason, except for a single scale and units: Are there any commercially available "Boost" gauges that are scaled, like 0 - 270kPa, which would be at about 100kPa at engine off; rather than -30" Hg to "0" to 25 psi?
It would be the same physical gauge, just scaled to correspond to the values we see on Tuner Studio.
Obviously, there is not enough action on MT.net to satisfy my addiction, so I pose this question.
DNM
It would be the same physical gauge, just scaled to correspond to the values we see on Tuner Studio.
Obviously, there is not enough action on MT.net to satisfy my addiction, so I pose this question.
DNM
#2
AutoMeter is one brand that does.
AutoMeter boost gauges
Edit: Sorry, now see you want kPa instead of PSI. The ones I could find were either 0-200kPa or 0-1000kPa [Defi brand]
AutoMeter boost gauges
Edit: Sorry, now see you want kPa instead of PSI. The ones I could find were either 0-200kPa or 0-1000kPa [Defi brand]
Last edited by bahurd; 05-21-2019 at 02:54 PM.
#3
Interesting request DNM lol. A style of gauge I've never thought of. It seems there are no actual off the shelf options of that in my super quick search.
Closest thing I found was this https://www.extremepsi.com/store/pro...roductid=19825 but it's not quite as detailed as I assume you are desiring. Only goes up to 200 kpa as well, so not for a ton of boost.
Looks like you just need to make a digital dash so you can have it in kpa right in front of you
Closest thing I found was this https://www.extremepsi.com/store/pro...roductid=19825 but it's not quite as detailed as I assume you are desiring. Only goes up to 200 kpa as well, so not for a ton of boost.
Looks like you just need to make a digital dash so you can have it in kpa right in front of you
#4
I've never seen a mechanical absolute pressure gauge. I'm sure it's possible (perhaps by having a reference chamber that's in a vacuum), but probably expensive/unreliable.
--Ian
#6
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Actually, it wouldn't be the same physical gauge. Cheap mechanical boost/vacuum gauges measure relative pressure (or "gauge pressure"), with the reference being the ambient atmospheric pressure, while the Tuner Studio value is absolute pressure. If you were to rescale it at sea level and then go up 5000 feet in altitude, it'd show 100 kpa MAP when it's actually 80-ish.
I've never seen a mechanical absolute pressure gauge. I'm sure it's possible (perhaps by having a reference chamber that's in a vacuum), but probably expensive/unreliable.
--Ian
I've never seen a mechanical absolute pressure gauge. I'm sure it's possible (perhaps by having a reference chamber that's in a vacuum), but probably expensive/unreliable.
--Ian
DNM
#7
In my mind it would be the same gauge, but you make the correct point that it would not be accurate. I guess the gauges that now exist will always show boost vs ambient, which are also incorrect vs the MAP reading in boost that is true absolute. If I have my EBC set at 15 psi equivalent ((202 kPa), then at high altitude, my Boost gauge will show like 18 psi, and the re-scaled one I mention would show 222 kPa. Both equally inaccurate vs the true MAP.
DNM
DNM
The boost gauge is telling you the truth when shows 18 psi for a 200 kpa MAP at altitude. Technically it should probably have "psig" (g for gauge) on the face instead of just psi, but that's implicit.
--Ian
#9
There are a few to choose from. One from Apexi and one from HKS. Also there is a DIY on here from a member. I'm sure there are more, these are just the first I found.
https://www.miataturbo.net/diy-turbo...e-53870/page2/
https://www.extremepsi.com/store/pro...roductid=19825
https://www.kseriesparts.com/HKS-44004-AK002.html
https://www.miataturbo.net/diy-turbo...e-53870/page2/
https://www.extremepsi.com/store/pro...roductid=19825
https://www.kseriesparts.com/HKS-44004-AK002.html
#11
https://perfecttuning.net/en/gauge/5...uge&results=52
#13
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Six. Yep, those would certainly work. Electronic gauges that work right off a MAP Sensor. Not sure how one would run them as gauge pressure with a single sensor, however.
#15
A fun option would be to get a custom MAP gauge face for a cheap mechanical vac/boost gauge from Revlimiter or somewhere. You could even DIY RTV seal the case at sea level if you really care about how absolute your pressure is
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