[Diy_efi] Temperature/Pressure sensors

[Alex Garbino]

Hello,

I'm trying to build a data acquisition system to monitor various
temperatures and pressures. I've been looking at thermocouples, RTDs, and
thermistors; but they have widely different advatnages and disadvantages. I
was thinking of using thermistors to monitor air intake temperature &
pressure (on a turbocharged car, so I would like to monitor atmospheric,
pre-intercooler, and post-intercooler/manifold) as well as coolant temp, oil
pressure & temp, and EGTs, both before and after the turbocharger.
Thermistors seem the best choice for air intake, since they have a fast
response and are cheap; however, I cannot find good datasheets regarding the
linearization coefficients.

Does anyone have advice on a good way to capture data, as well as any tips
on the best way to mount these sensors (a modular system would be best, so I
could move sensors to different positions and switch them in and out with
minimum hassle)? Also, can anyone recommend a good source of cheap sensors?

The signals will be captured via a PIC18F series' A/D converters/digital
inputs, and relayed immediately onto an on-board computer. Please let me
know of any resources that would be helpful!

Regards,
Alex

For a more detailed discussion on what I'm trying to achieve, please see
http://www.mkiiitech.com/forums/viewtopic.php?t=903