Temperature sensors-real time type
 

I have a Porsche 914-8 conversion project going. It has a hot Chevy 327 and I am having overheating issues. We are trying to debug the system. I was wondering if anyone knows of temp sensors that can be taped or attached to various locations and have some sort of readout in the cockpit.

I know there are data acquisition devices but some of these get really expensive. Plus I only need it attached during the testing phase so a permanent installation is not needed.

Does anybody know of a relatively cheap, reliable system that can handle multiple sensors?

thanks
Fred

well i have no idea about multiple readouts but what about doing a test run and then bringing it back in and reading various places on the block with a laser thermometer.

We did that and about the best we can calculate is the temp drop across the radiator. I am hoping to find hot spots in the cooling system. The block is basically the same temp all around, and the heads are way hotter than the coolant ever gets. Ideally I would put the sensors along the hose that runs from the block to the front (radiator) and back again.

Another idea was to try and measure the liquid flow through the system. I am thinking a flow meter would create too much of a restriction. And if I was really creative, I would put pressure sensors in various spot in the front trunk to make sure we are venting the radiator air properly through the wheel wells.

How about a number of senders/gauges and some dude writing it all on a note pad?

Hope he can keep up! :)

I am not sure an infrared reading is the best, I think a sensor strapped to the hose is better, but not ideal. The best would be a sensor in the water flow itself, but you don't want to start sticking in a bunch of connections in the system you can screw a probe into.

I am open to suggestions. Mainly I am shooting for something that can be read while driving with the engine at various RPMs. I know there are home kits you can build and tie into circuit boards, but I am hoping for something between that and an expensive data acquisition system.

Take a look on Ebay and see what type of temp gauges they have. I often find this type of gear fairly cheap on Ebay. Lots of stuff coming out of Asia.

Has no one ever built a small block to your specs before ? Certainly cooling one of these motors has been done many times before...I know that a 914 is a small place to put a small block, but wouldnt a set of EGT meters or Air/fuel ratio meter do the same job you are looking for ?

What, other than a lean or rich condition, would cause "hot spots" at one rpm and not another ?

Perhaps a trip to a chassis dyno would let you load the engine while looking for problems with the infrared.

-John

1. How many temperature channels do you really want to read at (essentially) the same time?

2. Is datalogging important?

3. Do you have a Windows laptop that you could use as part of the test?

Good questions. EGT might tell me if the engine is too hot but not too much about the cooling system. I am looking for different heat output at various speeds, not necessarily a specific RPM hot spot. There may be a speed where the cooling system can't keep up and then when you are below that, it takes a long time to come back down.

4-6. I would like inlet and outlet of the radiator, inlet of the water pump and outlet of the block.

Logging is not critical.

I could get a laptop, no problem.

thanks
Fred

I don't know if it falls in the realm of "really expensive" or not, but I'd bet you could do a lot with something like this 8-channel USB thermocouple interface from Measurement Computing.