SiZzOuRcE

Did a quick search to see if anyone has done this, and couldn't find much.

Anyways, I used to own a Dodge Ram Hemi before my xB. One of the mods I used when spraying my truck with nitrous (to be on the "safer" side) was a cooler thermostat to keep the motor a bit cooler when running it hard.

The temp of the stock thermo was 215 I believe and the one I put in was a 180 degree. The best example of this is starting your car cold, compared to running around for about 20 mins. From my experience, cold start ups usually feel a little peppier.

Has anyone tried finding a cooler thermo for our cars? I plan on running a 50 shot on the box and using a cooler thermo should help keep the engine temp down.

XD40tC

Agreed about the start up and go fastness of any car. It feels like 20 more hp lol until it warms up. I would like to run a cooler tstat in my box mainly so things last longer.

ScionFred

iTrader: (1)

I installed a <$10 Stant 14077 (170F) stat in place of the oem 180F stat when I installed my turbo. There is also a 160F TRD stat for the SC kit but I bet it costs an arm and a leg from the stealer ($25 for a gal of Toyota antifreeze?). I drilled a 1/8" hole where the oem 'jiggle valve' is to allow air to bleed out a little faster. Probably not necessary but not harmful either.

TrevorS

iTrader: (1)

I was wondering about that! It's hard to believe there's no aftermarket product that will satisfactorily approximate the same job.

Beyond that, I switched from a 190F Stant to a 180 Stant in my Eclipse, and if there's a resulting difference, I haven't detected it.

ScionFred

iTrader: (1)

Stant also offers a oem style stat complete with jiggle-valve but only in the oem 180F. The 14077 falls into the "fits" category. +/- 10F won't make much difference but if you follow the "every little bit helps" philosophy, it might be enough to keep a bit richer afr and timing advance on hot days.

FWIW, the oem stat appeared to be much higher quality than the Stant replacement. Perhaps the TRD stat is worth the extra $ but I doubt that many (if any) dealers stock it and 160F might be too cold for most NA apps.

curtislo9

I will be installing a 170 degree one on my car tomorrow

ScionFred

iTrader: (1)

My only advice is to take your time bleeding out the trapped air after changing the stat. I drained 1 gal, added 1/2 gal and thought I was okay to "drive out" the remainng air. Wrong! My engine overheated within a few miles and I limped it home with the temp gauge pegged on HOT. It was pretty scary.

What I learned was to let the tank overflow as the system pushes out coolant ahead of the trapped air. It makes a mess and wastes coolant but it works eventually. I lost about 1/2 gal of 50/50 Toy AF/distilled water while purging air.

Be sure to use distilled water!

curtislo9

So follow this, even when replacing the radiator?

ScionFred

iTrader: (1)

All I can say definitively is that my XB was the most difficult vehicle to purge trapped coolant system air from that I've yet encountered. In my case it was made harder by the replacement radiator hose/pipe included in my turbo kit. I would recommend measuring how much coolant you drain vs how much you add to determine when it's safe to "drive" any remaining air out. I think that a difference of 1 qt or less would be okay.

The recommended "driveway" procedure seems to be to let the engine idle with the overflow tank cap removed until the trapped air is purged through the overflow tank. Just keep adding 50/50 water/coolant until the air is purged. There are also special tools available but I'm sure it's cheaper to lose some coolant.

A-snell

iTrader: (4)

there should be a purge valve somewhere. so you don't get any air lock. it should be at the highest point in the coolant system. I haven't looked for it yet, but it would seem that there should be one...

ScionFred

iTrader: (1)

There should be but I couldn't find one, my dealer didn't know of one and the closest thing I found was the heater core hoses. There is a purge/drain valve on the bottom of the thermostat housing but it's far from the highest point in the system. The coolant temp sensor looks promising but I didn't try it.

SiZzOuRcE

If it's really only a difference of 10 degrees, I'm not sure how much benefit it would have but I guess every little bit counts. I might look into doing this sometime this weekend. If I do it, I'll post a diy.

ScionFred

iTrader: (1)

10F isn't much but the mpg and hydrogen guys claim that 10F is the optimal temp offset for leaner afrs when modding the CTS. Of course they're modding for a hotter temp reading and leaner afr, you're going the opposite direction.

FWIW, I think I've lowered my coolant temp by 10-20F with the Stant stat. It not only opens sooner, it opens further than the oem stat.