ST215w MAP sensor output - Graphable from this?

[TWSTD]

I need a graph (or equation) that describes the output of the ST215w caldia GT-T MAP sensor. Without a test bench to do the testing myself, is this enough information to make such a graph? Is it a linear curve? Has anyone else plotted the output of this sensor?

[Malcolm]

http://gtfour.supras.org.nz/mapsensor.htm

info there on the gen 2 and 3 map sensors. No good reason why the gen 4 shouldn't have the same linear output (not necessarily with the same values though)

[TWSTD]

Thought i had seen that before - thanks. I will check the part no on my GTT map sensor (which ive been told may be 2.6bar) and see if its the same unit as the gen3 tested there.

[strx7]

i wonder where you got that map sensor from

[vvega]

I need a graph (or equation) that describes the output of the ST215w caldia GT-T MAP sensor. Without a test bench to do the testing myself, is this enough information to make such a graph? Is it a linear curve? Has anyone else plotted the output of this sensor?

its is linier
all map sensors are
i belive there 26/28 psi

least thats what the one a had on my haltech was and that was off a gt-t

v

[TWSTD]

Seems the caldina sensor is not the same part as the Gen3 sensor tested here: http://gtfour.supras.org.nz/mapsensor.htm

P/N 89420-17030 This sensor is fitted to the 89-Oct93 MR2 Turbo and also (using a different P/N) the ST185.

P/N 89420-17050 This sensor is fitted to the Oct93-99 MR2 Turbo and also (using a different P/N) the ST205.

Caldina:
89421-21010

Maybe I now need to somehow setup a bench and test the output of the caldina sensor. I have a multimeter to measure voltage - anyone hav suggestions re accurate pressure source and pressure meter? Would a digital tyre pressure gauge and a large inflated tyre be suitable to obtain accurate results? I would have to make some kind of attachment to the valve to allow a feed to the map sensor...

[RunningRich]

A tyre gauge won't be very accurate, +/- 2 psi at best I'd guess.

I used (doing the graphs referred to here) a calibrated digital pressure meter, like a Fluke multimeter for air I guess! Worth about NZ$1000. PSI to two decimal places. Awesome.

Pressure source was a vacuum/pressure pump, used for testing EFI systems. It stuggled over 40psi though but did the vacuum well.

[TWSTD]

Would you be keen to repeat this testing procedure with 1 or 2 other map sensors Richard? Assuming you still have access to the equipment?

[RunningRich]

I don't have the gears any more

[TWSTD]

Damn. Anyone else here have access this this kinda equipment?

[MasCam]

Just a thought but couldn't you use a boost guage from a car just hooked up to a battery temporarily?

As you would have to make some conections to the map sensor for pressure you cold put the guage into the same system, the tyre for a pressure vessel is a good idea, the larger the vessel the less pressure variations you would have when trying to pump it up.

I can't think of any reason why you couldn't use a manual foot pump which would give you plenty of control over the pressure increases. It might take a while but if you had an accurate boost guage it should work fine. The only thing is I can't imediatly think of a good way to get the vacum.

[TWSTD]

from my experience theres no such thing as an accurate boost gauge - particularly to a decimal place or two!

[TrouserFxGt]

Damn. Anyone else here have access this this kinda equipment?

yes, send me a pm.

[vvega]

from my experience theres no such thing as an accurate boost gauge - particularly to a decimal place or two!

mitatoyo have oeb thats accurate 2 .001 i belive
its about 700 bucks

v

[Inane]

from my experience theres no such thing as an accurate boost gauge - particularly to a decimal place or two!

mitatoyo have oeb thats accurate 2 .001 i belive
its about 700 bucks

v

in theory any good electronic boost gauge should easily be accurate to a couple of decimal places.

[vvega]

cant really say that without knowiig the specs there built to
its not uncomon for a boost guage to only be acureate to 1 psi give or take .5

and very few are electronic
v

[Inane]

I know very few are electronic,

and the other problem is, do you want a boost gauge that is

A) precisely accurate
or
b) doesnt bounce around constantly shaking like an epileptic being electrocuted.

because thats the main reason boost gauges are inaccurate, built in buffer zone to stop the needle bouncing like a background dancer in a missy elliot video.

[MrOizo]

Go into dick smith electronics. order the bit you want (fluke meter with PSI meter) - they're resellers of the fluke range.

when you're done just take it back and say it wasnt what you needed. they have a 7 day right of return...

i used to work there and i even did it on a $3k laptop that we used over a weekend - got it on the friday and had it returned on the monday

just make sure with the store that you get it from and you can take it back and take it back to the person that agreesto do it all

they might not be too keen as its a order only bit but worth a shot

chur chur.

[fivebob]

Seems the caldina sensor is not the same part as the Gen3 sensor tested here: http://gtfour.supras.org.nz/mapsensor.htm

P/N 89420-17030 This sensor is fitted to the 89-Oct93 MR2 Turbo and also (using a different P/N) the ST185.

P/N 89420-17050 This sensor is fitted to the Oct93-99 MR2 Turbo and also (using a different P/N) the ST205.

Caldina:
89421-21010

Maybe I now need to somehow setup a bench and test the output of the caldina sensor. I have a multimeter to measure voltage - anyone hav suggestions re accurate pressure source and pressure meter? Would a digital tyre pressure gauge and a large inflated tyre be suitable to obtain accurate results? I would have to make some kind of attachment to the valve to allow a feed to the map sensor...

I believe they have the same output, because the have the same fuel cut level (or very close) and that is usually determined by voltage output not actual boost level. e.g. all 3S-GTEs will fuel cut at the same voltage level (approx 4.7v), but different boost levels according to which sensor they have.

If you're going to use it with an aftermarket ECU then in reality it doesn't matter if the curve is exact, you're tuning the engine to the sensors not to the exact pressure

[TWSTD]

If you're going to use it with an aftermarket ECU then in reality it doesn't matter if the curve is exact

I actually intend to use it with a factory ECU in a vehicle that uses a 2 bar sensor from factory