TB removal and then some!!!

[XfireZ51]

Sorry Marty, but there’s no way GM would allow the car to run at anything below the point where the ECM is not LEARNING and modifying the fueling for BLMs. No matter what the conditions. That’s part of what cold weather testing is all about.
The coolant needs to be at >80C for that. Anything below that for other than warmup is not what the calibration is looking for. That doesn’t mean it won’t run but it defeats the whole point of Closed Loop operation.

[Jagdpanzer]

Never been a fan of drilling holes in thermostats.


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[Mystic ZR-1]

Probably the thermostat was stuck open, be thankful it wasn't stuck shut.
Rather have it run too cool then too hot...
Replacing it should solve the problem?
Other than this, Happy New Year Tom!

[Ccmano]

Not sure I would immediately believe the gages. Hook up a scanner, Tech1 or such or get a reading from the other sensor via the HVAC display. Even if the thermostat stuck fully open I would still expect to see correct operating temp once the engine is fully warmed up, even in cold ambient temps.
H

[Roadster]

Originally Posted by Jagdpanzer

Never been a fan of drilling holes in thermostats.


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To my knowledge Phil....I don't think the thermostat has been drilled out.....but don't know for sure.....enjoy those wings.....

Originally Posted by Mystic ZR-1

Probably the thermostat was stuck open, be thankful it wasn't stuck shut.
Rather have it run too cool then too hot...
Replacing it should solve the problem?
Other than this, Happy New Year Tom!

I hear you there Doug.....didn't feel like a tow home would be in order today.....lol was much easier turning around and driving home.....a thermostat replacement may be in order......and a Happy New Year to you also Doug!!! have fun......

Originally Posted by Ccmano

Not sure I would immediately believe the gages. Hook up a scanner, Tech1 or such or get a reading from the other sensor via the HVAC display. Even if the thermostat stuck fully open I would still expect to see correct operating temp once the engine is fully warmed up, even in cold ambient temps.
H

Lol....and I had the Tech 1 with me....but was more concerned about getting home....lol And both the digital and the analog gauges were reading the same....whether high or low....so I would doubt the readings were false.....but good idea on the Tech 1.....why didn't I think of that.....lol It's just strange that at highway speeds the temp would drop 40*.....and local driving it appears to be normal....but really is not as the temp was dropping at least 10* when driving locally....but then return to normal when sitting at a light....hmmmm....need to sleep on this one.....lol a later afternoon snooze may be in order.....lol

[secondchance]

Tom,

About 4 years ago I installed a thermo stat with 3 1/8" holes drilled on the flange. It worked fine during the summer months resulting in about 10 degree drop. As soon as we hit cold weather, at highway speed, she was running at 140. Idling, temp would get up to 190 to 200. I would suspect you have a drilled thermostat also.

[Dynomite]

What deg thermostat do you have? Check Coolant Temp using digital readout #16 fan speed. Do NOT drill holes in thermostats.

It does take a long while to warm up all coolant in radiator. The thermostat can get confused during that initial warm up when radiator coolant is so cold. I do not see a problem.

Happy New Year



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[XfireZ51]

I installed a Fluidyne several years ago trying to address overhating innsummer w AC on. We put in a 180d thermo w 4 holes. It did as u described. Temps dropped to 150 or so when cruising in 30d ambient. Finally, settled on 2 1/8” holes using 180d thermo. Works perfectly in warm or cold. Hot weather driving,
temps are easily kept within the 187- 198d range. Fans come on at 190 and 192.
Cruising temps are below that. My cal for fans is set so temps are always in
Closed Loop Learn range.

[HAWAIIZR-1]

Originally Posted by XfireZ51

I installed a Fluidyne several years ago trying to address overhating innsummer w AC on. We put in a 180d thermo w 4 holes. It did as u described. Temps dropped to 150 or so when cruising in 30d ambient. Finally, settled on 2 1/8” holes using 180d thermo. Works perfectly in warm or cold. Hot weather driving,

temps are easily kept within the 187- 198d range. Fans come on at 190 and 192.

Cruising temps are below that. My cal for fans is set so temps are always in

Closed Loop Learn range.

Hey Dom,

My new garage is built so my car is coming home tomorrow. One of the first projects is the Fluidyne radiator I bought before moving here last year. What if I leave the 180 degree thermostat stock w/o drilling even two holes? Did you try your Fluidyne radiator with stock thermostat?

Thanks,
Craig


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[XfireZ51]

Craig,

My interest in better cooling was due to use of AC in hot weather traffic. Otherwise not much issue. Plus, w ~550chp, the motor is generating more heat than a stock motor. I would simply install a stock thermo w the Fluidyne. Should be fine.