I recently received the magnetic oil plug I ordered from LN Engineering, and a brochure was included in the package which describes a low temp thermostat that has my interest. Arkansas gets HOT in the summer, and the oil temps are steady at around 200+ indicated. It seems like lowering the temps on the engine oil to 25 degrees less would be beneficial in the long run toward engine and oil longevity. Does anyone have experience and or comments pro/con regarding these LN Engineering low temp thermostats and the benefits of having one installed? How would this affect the heater temps in the winter?

 

I'd think you would want the oil to stay above 212 degrees so you can boil off any water in the oil. The thermostat mostly regulates water temp anyway, that may be beneficial depending on the heat, but unless you track the car or live in the middle east, you would think that the car would be OK with the stock thermostat.

Lots of sitting in traffic might be a consideration, but I don't know what your area is like in that regard.

 

The thermostat i not something i recommend changing. What we want is the oil to get to operating temp in fastest time possible. The oem thermomdoes this now if you lack cooling capacity and oilmgets too hot the thermostat is not the answer. You need a third radiator .

 

Harteg says the cylinder cracks/block failures are due to rapid spikes in temperature not steady state overheating like you might see on racetrack. 3rd radiator will keep overall temps down but he says wide open throttle with thermostat not full open causes heat spike which cooling system is slow to respond to. Thus lo temp 'stat which is open earlier. I think for the street that it is important to get to runnung temps asap. For track 3rd rad is good. I don't know what to make of the thermostat change but imo longer warmups cannot be a good thing over the life of a street engine.

 

Thanks for your inputs, guys. All good points. I think, since I won't be tracking this car or running it really hard, that I'll stick with the stock OEM thermostat. I also haven't experienced any overheating, and the dash gauge warms up to a constant indicated within about 5 - 7 minutes with no indication that additional cooling or lower temps will be any advantage.

 

I have both the third radiator & the LN low temp thermostat. Adding the radiator did not lower the coolant temperature and had little to no effect on warmup time. The thermostat had the effect of lowering the oil temperature 10 to 15 degrees, with no change to coolant temperature. Lower is better.

The coolant gauge is known to read out temperatures less than maximum in the engine. 175 gauge can be 200 elsewhere in the cooling system.

The engine oil and coolant are actually interconnected thermally, there is a heat exchanger on top of the motor that provides a quicker warmup of the oil. For hard core racing, this can be removed, a special fitting (LN has one) installed, extra oil lines run and a second oil radiator with fan installed in the nose.

 

michael summed it up perfectly. oem thermostat stays and if you need extra cooling use 3rd rad. however i doubt if changing the thermostat will not affect warm up time. it will as it opens earlier and the engine has to contend with warming up more water before it gets to its proper operaiting temperature or course this is relative to the oem or any higher set thermostat.

 

Slight misunderstanding. You do need the low temp thermostat for lower oil temperatures. Its effect on warming time is minimal. No drawbacks with this part. The third radiator by itself did not lower oil temperatures.

 

my mechanic has this opinion: motor is optimized to run at particular operatinng temperature - and this is 190 degrees. 160 deg thermostat may do some help reducing coolant temp but it will do more damage keeping block cooler than it was intended to be. you definitely must have 3rd radiator installed if you do not have it - this will lock coolant pretty much to 191 deg and it will rarely get any higher and it should be sufficient enough to avoid 6th cylinder overheat.

 

The engine temperatures are well above the indicated 175 degrees in parts of the motor. The 160 degree thermostat may reduce these. The reason the higher temperature stock (180-185?) part is used is to speed up engine warmup for meeting emission standards. Seconds are hours here.

Cars set up for heavy duty usage will frequently have the low temperature thermostat, third radiator, deep sump and/or oil system improvements.

One oil system upgrade is the "Accusump", which is a pressurized reservoir of oil that is let into the oiling circuit if the pressure falls in heavy cornering (there are scavenge pumps in both cylinder heads for this reason & 4 pump aftermarket conversions can be fitted). Sometimes used for short tracks or autocross.

The stock heat exchanger above the motor, which interconnects coolant and oil systems thermally, can be removed. It is replaced by an adapter, which is fitted with oil lines running up to the front of the car. A second oil cooler, with fans, is rigged near the stock oil cooler. This setup can reduce oil temperatures significantly, but greatly increases time to fully warm up. A real benefit is increased oil capacity, probably gets it to 12 quarts. Not commonly used for street driven cars.

 

somebody got to explain to me how a 160F runs cooler than a 190F thermostat ?

once water temp hits say 190F (normal optimum wt for a gas combustion engine is around 200-220), both thermostats are now fully opened. what difference does it make ?

 

I'm w you here. The vendors theory is that the thermostat is fully open sooner and therefore more able to provide full cooling flow should there be a sudden temp spike to the cylinder head. Since the motor is designed to run steady state at 210 or so whats the advantage? Is it more opener? As for the reduction in running (water) temp, the oil temps should be in the 200+ range to boil out condensation and operate properly. A third radiator should not lower normal running temps because that is not a good thing; ergo it does nothing unless you are tracking the car.