to those with aux water temp gauge - cluster vs aux readings??

[Sh3rpak!ng]

Is your sender for your temp gauge threaded into the head? I try to shoot the IR right next to the sender on the head to see if my gauge is reading correctly. The thermostat cover is also generally pretty accurate once you reach operating temp.

Did you get a big temp difference between the hot side and cold side of the rad?

yup, temp gauge sender is in the head. Unfortunately there's stuff in the way to get a clear shot at the head next to the sender. Also, with the big radiator, and already tight clearances, it's also nearly impossible to get a clear shot at the thermostat housing.

It's also difficult to get an accurate reading on the all aluminum radiator. Apparently it has something to do with emissivity. I wonder if striping areas with black electrical tape would help get a better reading. That said, I seemed to get a decent? reading from pointing it at the face of the radiator.

I'll attempt some more readings tomorrow and report back.

[RoccoB517]

Is your sender for your temp gauge threaded into the head? I try to shoot the IR right next to the sender on the head to see if my gauge is reading correctly. The thermostat cover is also generally pretty accurate once you reach operating temp.

Did you get a big temp difference between the hot side and cold side of the rad?

[Sh3rpak!ng]

My gauge generally shows 200-210 when the cluster needle is dead center, but my standard operating temp on the track is 180-190 and at those temps the cluster needle is showing at roughly 1/4.

hmm so that sounds about right with what I'm seeing, aside from your standard operating temp on track...

I just don't get it. In my e36 I have a stock radiator, stock water pump, 80c thermostat and I see a pretty solid 180-190 on the aux gauge in that car. I would think with the cooling upgrades in the e30s52 temps should stay rock solid around whatever the thermostat temp is.




Additionally, I let the car idle at operating temp yesterday, took readings with an IR gun and checked both gauges to see where they settled.

Idling, cluster gauge showed a needle width to the left of dead center. Aux gauge showed about 203-205F and I measured a myriad of temps depending where I aimed the IR gun. The aluminum radiator seemed problematic to measure temps on... the hose inlet measured 210+ as did the radiator face.

[RoccoB517]

My gauge generally shows 200-210 when the cluster needle is dead center, but my standard operating temp on the track is 180-190 and at those temps the cluster needle is showing at roughly 1/4.

[Sh3rpak!ng]

I have an s52 swapped e30 with a stewart water pump, 48mm radiator, 88c thermostat, no clutch fan, spal pusher 1600 cfm

with this combination I would expect to see the aux gauge reading a solid 190F during daily driving but it does not.

I see a solid 200-210F on the aux gauge, and as high as 220F. The cluster gauge reads either dead center, or one needle width to the left of dead center. I have never seen it pass dead center. And this is with all types of driving, stop and go, highway cruising, canyon carving and IIRC even at autox it was solid at those numbers.



What do your aux gauges read when the cluster gauge shows the needle dead center/one tick to the left of dead center?

I'd like to try to determine if the gauge is reading accurately or not before I start pulling stuff apart.