oil temp & oil press fitting location,

[Lude]

i was going to put my oil temp sensor into the sump plug,

 

using one of these

http://www.racingworks.com/images/greddy_oilpan_temp.jpg

 

 

and then using a T Piece, put the oil pressure sensor where the stock sensor is.

 

 

can i use a 3 piece T piece and put the Greddy oil temp sensor & Greddy oil press sensor where the stock oil pressure is?

 

 

or any other recomendations? is it a bit dangerous the oil temp in the sump incase car grounds? (or is the sump plug out of sight of the floor)

 

 

PS here is my T Piece, you can put 3 things into it (1 where the gold bolt is on the top, 1 where the braided line is, and 3rd on the end)

Edited August 24, 2010 by Lude (see edit history)

[David Reid]

An easier way is to use a spacer plate on the oil filter. I have one unfitted at home I'll get some pictures up.

 

I think the sump plug faces sideways so you will have no problem, just consider that actuall oil gallery temperature can be 15-25 degrees above sump oil temperature, so its not going to give you a true indication of actual peak oil temperature.

Edited August 25, 2010 by David Reid (see edit history)

[Lude]

ok, i read that the sump was the best place?

 

 

i had a sandwhich plate before on an old car and the gauges didnt get any readings there? or it had oil pressure but not temp,

 

that was on my 200sx, but if i put the gauge anywhere else it would?

 

 

going to just put my Greddy oil pressure where the stock one is (asume same thread size, was on my 300zx)

 

use my double adapter thing so can have the stock & aftermarket reading

[David Reid]

ok, i read that the sump was the best place?

 

 

Thats the internet for you, there is a reason why no OEMs use sump temperature and only gallery

 

If you have 3 ports on the T why not put them all in that?

 

I dont understand why your sandwich plate didnt work as if oil is passing the sensor it can't not work. Did you check to see oil was actually flowing through the plate?

[Lude]

no idea why the sandwhich plate didnt work before, i just sold it and got the triple adapter bit.

 

i wasnt sure if you could put the oil temp the same place as the oil pressure goes, as doesnt get the correct readings?

 

 

but if its ok il put them all in the 1 place

[Nic]

I'd use an Oil filter sandwich plate, GReddy do this one to fit 2 sensors.

 

http://www.trust-power.com/03electric/img/sensor_atach.jpg

[Chris Wilson]

Oil temp where sump plug is, oil pressure from a drilled and tapped stock oil filter housing bolt.

[David Reid]

Oil temp where sump plug is, oil pressure from a drilled and tapped stock oil filter housing bolt.

 

Chris why do you say sump plug do you assume an offset for true gallery temp?

 

I know I have had alot of problem with the manufacturer I work with using sump temperature, for Oil based VVT units oil temp makes a huge difference to the position control. We had lots of problems with control due to the error between gallery and sump temperature, so much so we had to implement a complex model to estimate gallery temperature from sump temperature with a load of other inputs.

 

At the time the problem was discovered it was too late to change the sensor location, but I know that it moved to the correct place for the next model year.

[Digsy]

For general use the oil pan is a fine place to put the oil temp sensor as it is a large mass of oil so the reading will be relatively stable. It will also probably be the hottest oil you will find as it will have "done its work" and just have dropped out of the engine. On an engine like the 2JZ with its oil / water cooler this will certainly be the case as the moment the oil gets into the engine proper it will have a few degrees knocked off it as it passes through the cooler.

 

Checking oil temp for variable valvetrain, where the response characteristic is linked to the oil temperature is a special case which I agree would require a sensor in a gallery somewhere close to the VVT pulley or oil control valve.

[Chris Wilson]

I recommend that place as it involves only a 4 quid adaptor, no drilling, risk of swarf or expensive sandwich plates with possibility of leaks. As Digsy says, it's, AFAIK, generally the hottest oil that's easily probed, too. In what way does oil temp affect VVTi? Is it the viscosity and leakage around the plunger piston?

[Digsy]

In what way does oil temp affect VVTi? Is it the viscosity and leakage around the plunger piston?

 

In my experience its more to do with the point at which you can safely / reliably demand a change to the cam timing and expect it to happen within the required timescale. As you know oil pressure changes with oil temperature, as does flow rate at a given pressure. Its the oil pressure that gives the "oomph" to actually move the cam pulley, and but the flow rate that gives the response time, so you can imagine when asking for a cam timing shift just after a cold start you may have the pressure to do it but not enough flow to move the pulley fast enough.

Its a can of worms for the calibration guys, but it depends on how clever the control software for the the VVTi is trying to be and under what conditions you need to be able to control the cams. Its not quite the same thing but I believe the switching tappet that Porsche uses is allowed to switch to high lift almost from engine start, but not allowed to switch back again until after the oil has reached a certain temperature because switching back relies on the oil getting out of the tappet and allowing it to compress again, which is difficult when the oil is cold and thick.

[Chris Wilson]

This is very very interesting to me, would you say on a VVTi 2JZ-GTE engine a change of cam to one with more duration and lift and stronger valve springs could significantly change the loadings on the pulley mechanism and alter the way it either functions or responds? Thanks.

[Tricky-Ricky]

I can see where David is coming from, working with the engineering side of a fluid mechanism, he is going to see a different side of things to us guys with just a view to getting a reasonable overall view of oil temps, especially when running big single turbos etc.

 

I was always under the impression and experience that the gallery temps on the Supra tend to be around 10-12C higher that the sump oil temp.

[Digsy]

This is very very interesting to me, would you say on a VVTi 2JZ-GTE engine a change of cam to one with more duration and lift and stronger valve springs could significantly change the loadings on the pulley mechanism and alter the way it either functions or responds? Thanks.

 

Possibly. It all depends on the maximum acceleration on the valve. You mention a cam with a higher lift and a longer duration, which makes me think that the maximum acceleration might not be effected because there is more time (duration) to move the valve from rest to MOP and back again. However, the fitment of stronger valve springs suggests that for some reason more spring cover is needed so the accelerations (or the mass of something else in the valvetrain) must have changed.

Assuming the accelerations or masses (and hence forces) have increased then there will be a change in the average drive torque on the cam pulley, which might well affect the phaser operation. In a vane-type VVT pulley, if the forces increase the phaser will retard faster than it will advance due to increase friction in the system. However the 2JZ uses an old-skool double-helix phaser which should be less senstive to being driven backwards directly by the camshaft drive loads.

But in summary, anything that increases the valvetrain drive torque will affect the phaser operation to some degree. Actually assessing how much is a bit long winded and requires details of the cam profile and accurate valvetrain masses (which is easy to get) and also some inside knowledge of how much torque the phaser produces per bar of applied oil pressure. The latter can only come from either the phaser supplier or through stripping down a phaser unit and working it out from first principles.

[Digsy]

I was always under the impression and experience that the gallery temps on the Supra tend to be around 10-12C higher that the sump oil temp.

 

Do you mean the main gallery, or higher up in the head? The main gallery is immediately after the oil cooler so I would hope that it was cooler here than the oil in the pan. Of course I haven't measured it myself, so if you are going from experience its a bit surprising!

[Tricky-Ricky]

Do you mean the main gallery, or higher up in the head? The main gallery is immediately after the oil cooler so I would hope that it was cooler here than the oil in the pan. Of course I haven't measured it myself, so if you are going from experience its a bit surprising!

 

I am referring to using a sandwich plate/filter spacer for the temp probe, and i was using a highly accurate thermocouple, when i changed it to the sump i was seeing that sort of drop in average temperature, i can only surmise that although the cooler kind of does its job, because of its proximity to the cylinder walls and head there is still a lot of heat transfer,

it surprised me, however i have seen this also reported by others.