Anyone got pics of how they drilled their t-stat? I need to get my car running cooler and don't really wanna buy a new tstat when this one is new.


Thanks Nate

you uhhh.. drill a hole in it.


-justin

Don't do four. That'* summertime hot-climate stuff. Drill two 1/16" diameter holes across from each other, so the rubber seal won't overlap them. De-burr with a larger drill bit, top and bottom, and rinse well before install.

These are 1/8" holes. This is HOT DRAGSTRIP thermostat material. Your holes need to be smaller.

That was a much better explination than mine.


-justin

:?: Anyone care to expound their theory on what the holes are supposed to do? :?:

uhh.. let coolant through. It helps to keep the temps down in warming of the engine, taking slightly longer to get up to temp when cold. However, I believe it also lets more coolant through once the tstat opens up, allowing for better cooling.


-justin

The holes allow for a slower warmup, helping to prevent initial heatsoak. It also allows more to pass when the therm is open as well, but not much.

Thanks for the info guys. How much of a difference does drilling the t stat make vs buying a 180 or 165 t stat? Are the holes worth 15 bucks?



Thanks,

Nate

the drilled theremostat also helps prevent hot spots in your heads. if you plan on doing a pulley on your car then get a 180* thermostat. they cost like $6-$7 at advanced auto and drill it yourself like the picture that willwren put up. this is an easy do it yourself job

The aspect that some forget is this:

Until the thermostat opens, the coolant in the engine near the thermostat isnt moving. Convection (hot rising, cool falling) means that the coolant right around the thermostat must pick up to AT LEAST (and then well past) the thermostat opening point before it reacts by opening. By the time it opens, the coolant is over that rated temperature - meaning it has to play "catch up". For proof - next time you jump in the car with the engine cold and then get it up to operating temperature, you'll see the thermostat open (late, higher than its rated temp), then the coolant temp falls down below its rated temp, then it swings back higher again and finally settles on its happy place. It doesnt seem to matter whether its a standard stant or Robertshaw type, they all seem to do it.

Drilling a hole in it does marginally lower the temperature rating, but it allows coolant to flow past the thermostat and allow it to react to cold-start warmups without the temperature swings. I've never drilled one and not been happy with the way it operated. I can't say the same for ones straight out of the box.

Older thermostats (ones that were made up into the 80s) had a small passange made into them for this purpose, but its not there anymore from my checking.


My opinion is that thermostats are trying to establish a miminum operating temp for the engine rather than trying to regulate a maximum temperature.