KenRudd

I would like to begin monitoring / logging my oil and brake pressure while on the track, sending data to my on-board logger. ( Also considering water temp, oil temp, diff temp)

Has anybody else added secondary sensors for these systems?

I see this from Lindsey racing for a secondary oil sensor, anybody used it?



What about brake pressure, best solution to install a sensor in that system?

For all these systems, but especially brakes and oil, must be dead on reliable, no reasonable chance of leaks or interference with function.

Simple is better.

Bambalam

Hi Ken,

Sorry for the late response here but I have been putting a drawing together for my ideas on an oil temperature sender adapter, I also like to monitor the oil pressures and temps - amazing how much longer it takes for the oil to warm up than the water.

I bought one of those Lindsay adapters and it appears to work very well to run an oil pressure gauge. Initially I thought I could run a temperature sender from here as well with a modified VDO adapter but there wasn't an oil flow to really get a good idea of the temp. I prefer to measure the temp at the inlet side of the oil cooler and fortunately I have a 90 S4 with the external oil cooler and in the past I have turned up a up a piece of brass hex bar to run between the block and the oil cooler line.

Drawing below shows the piece I will get a shop to turn up for me this time (don't have access to a lathe anymore) out of 32mm brass hex bar. I might have to modify the cooler line to fit but my biggest issue is where my piece will screw onto the adapter from the block. As shown as well the oil cooler has a conical end to fit in the taper but this will be impossible to turn into the internal thread in the hex bar (hope this makes sense - otherwise I will add a few more photos.

More than happy to share the drawing for anyone else and any comments or ideas would be appreciated especially if any of the dimensions are wrong (apologies for the metric dimensions).

Hope this helps, I will post some more pictures once the adapter has been made.

Simon

KenRudd

Simon,

I like your idea and it looks straight forward. It makes me wonder that if somewhere buried on an obscure page in the McMaster-Carr catalog, that part does not already exist...

Please keep up posted. I was working on the assumption that since the oil cooling was essentially an intercooler into the water cooling system, that once things got to temp, oil temp would never likely get too far out of line from water temp, unless something was very bad, but that could be just wishful thinking.

In any case, oil pressure is my tier 1 main focus because of the potential issues around that system. Tier 2 will be water temp and transaxle temp, and if your adapter works and is easily replicated, I'll add oil temp to that monitoring.

KenRudd

"I might have to modify the cooler line to fit but my biggest issue is where my piece will screw onto the adapter from the block. As shown as well the oil cooler has a conical end to fit in the taper but this will be impossible to turn into the internal thread in the hex bar (hope this makes sense - otherwise I will add a few more photos."

What if you also just made a quick female-to-female plug that sat inside your joint, like cutting the tip of two oil cooler hoses and joining them together, should be easy enough to turn on a lathe. Pardon my crude drawing, but this should help:

Bambalam

Hi Ken, good idea there - you have me thinking, I wondered about some type of "onion" I think they are called and maybe that is the way to solve the sealing problem with the connector to the block - I will draw something up and talk to my shop. A quick thought I also had here was that with the thermostat for the oil cooler system maybe we wont get a temp reading until it opens - is there a better location for the sender.

I also think that monitoring the oil pressure is critical as it is gives an instant reading to any problems, I just find that the oil temperature gives a better indication as to when the engine has reached operating temp especially on a racecar but also is interesting to compare the water and oil temp - I think the oil temperature gauge is the more critical reading.

Good analogy on the oil cooler being an intercooler for the system - I agree. I have made a couple of these and also surprised I cant find anyone that makes these as well - good to see Lindsay Racing making the temp adaptor.

I am also looking into an alternative location for the water temp monitoring - wondering if I can use the plate on the head that sits opposite the heater tap location.

Good to see someone else is interested - I will keep you posted.

Simon

KenRudd

Simon,

Instead of tapping into cooling line, why not take advantage of the existing cover and opening on the front of the oil pan:



That cover could be tapped pretty easily to accept sensor.

Challenges:

I don't know if that would actually have the sensor submerged in oil. When I get a chance I will eyeball oil level based on dipstick held up next to tube and pan to get a feel of how high oil comes into oil pan, but even that won't be accurate, as the oil level will drop by some amount as motor is running, and my oil pan has a spacer, so it may not match yours.

If that location does not get the sensor adequately submerged, you may be able to machine a "cup" to set the sensor farther down into the hole, similar to this:



This would still require some time on the lathe, but it looks to be an easier part to turn that the original hose adapter.

Plus, there is much less chance of a leak. With the initial design, you are adding two more spots that oil could leak under pressure. Using the oil pan access, pressure would not be a factor, it would be easier to seal and any leak would be a weep.

Bambalam

Good idea Ken, unfortunately my car doesn't have that plate but there is a flat blank section there that I could certainly work with and as you say it isn't under pressure so reduces the chance of a leak.
I was talking to my shop yesterday and there are also alot of difficulties with the location of my adapter due to the tight space and therefore having to modify the oil cooler line to fit, they had some good ideas but would require cutting up the line and adapting it in the flexible section to accommodate a sensor location - my thought was to get another line from a breaking yard that was damaged anyway to try this as I dont really want to cut things up.
This has also raised the question of what reading I will get due to the thermostat on the oil cooler, I have attached a diagram of the flow around the filter and thermostat and it certainly indicates that I will not get a reading until the thermostat opens, in fact from looking at this I think that the best idea would be a sandwich plate at the filter (although I think the filter is bypassed until some temperature is reached as well).

So your option is a good idea - I have run the sender in the sump plug before and you do get a good indication of the operating temperature of the oil - I was just hoping to get a reading in the actual flowpath but maybe that is not necessary.
There is a very similar plate that I was going to tap for the water temperature on the head opposite the heater tap - I wonder what that will yield in comparison to the water bridge.

Anyway good to study up on isnt it - good to have someone else interested - thanks Ken.

Simon

PS - I hope I am allowed to reprint this picture mods - I will take it down if necessary.