02' c5z - which thermostat
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Joined: Jan 2015
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From: CA; Bay Area
02' c5z - which thermostat
Hi,
I'm replacing the water pump on my 02' c5Z and will also replace the coolant tank/cap. What rating thermostat should I replace mine with?
My c5Z is all original.
Thanks in advance.
I'm replacing the water pump on my 02' c5Z and will also replace the coolant tank/cap. What rating thermostat should I replace mine with?
My c5Z is all original.
Thanks in advance.
Last edited by jvmagic; Apr 17, 2020 at 01:13 PM. Reason: all info
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From: Redondo Beach CA
I would not try to out engineer the original engineers, so the stock part , designed to match stock engine systems would be my choice,
From reading here, some like to move the opening temperature on a stock engine, and it is no big deal, but the engine was tested to go 200, 000 miles with all the systems as designed.
From reading here, some like to move the opening temperature on a stock engine, and it is no big deal, but the engine was tested to go 200, 000 miles with all the systems as designed.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 101
Likes: 3
From: CA; Bay Area
I would not try to out engineer the original engineers, so the stock part , designed to match stock engine systems would be my choice,
From reading here, some like to move the opening temperature on a stock engine, and it is no big deal, but the engine was tested to go 200, 000 miles with all the systems as designed.
From reading here, some like to move the opening temperature on a stock engine, and it is no big deal, but the engine was tested to go 200, 000 miles with all the systems as designed.
What’s the stock thermostat rating?
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2020 Corvette of the Year Finalist (performance mods)
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stock or 180 at the lowest would be my choice, I am not a fan of 160s at all... if you want the car to run cooler at idle just have the fan settings adjusted in the tune, that's really all you need to do
Drifting
Joined: May 2007
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From: Mid Ohio
I know a thing or two hundred about this subject. (I am a OEM engineer, was a water pump engineer back in the 90s, and have tuning experience)
I am a fan of running a slightly cooler T-Stat. But you MUST adjust the tune and accept that the exhaust emissions will not meet the intent & calibration set by Chevy trying to meet government standards.
There are three benefits to running a cooler coolant temp.
1. Timing can be increased (more power is the only real reason people run a cooler TStat)
2. Underhood temps decrease which helps everything last longer. (a higher Δ T = ALL parts under hood also have larger thermocycles which reduces lifetime. Especially plastics and rubber parts)
3. AC performance will get slightly better.
Only go cooler than stock if the tune has been adjusted for it.
- In the tune there are settings for switching to closed loop (PCM uses 02 sensors)
- In the tune, a good tuner will adjust the temperature gradient scale so that timing and fuel is adjusted during the warm up time.
- The fans can then be adjusted to come on earlier and keep the coolant and engine room temps cooler.
Downsides are two.
1. Emissions might not meet gov standards.
2. Heater performance is diminished.
btw there is a rule of thumb for cooling. 20% of the heat produced goes into the air surrounding the engine, 40% goes out the tailpipe, 40% goes into the cooling system.
I am a fan of running a slightly cooler T-Stat. But you MUST adjust the tune and accept that the exhaust emissions will not meet the intent & calibration set by Chevy trying to meet government standards.
There are three benefits to running a cooler coolant temp.
1. Timing can be increased (more power is the only real reason people run a cooler TStat)
2. Underhood temps decrease which helps everything last longer. (a higher Δ T = ALL parts under hood also have larger thermocycles which reduces lifetime. Especially plastics and rubber parts)
3. AC performance will get slightly better.
Only go cooler than stock if the tune has been adjusted for it.
- In the tune there are settings for switching to closed loop (PCM uses 02 sensors)
- In the tune, a good tuner will adjust the temperature gradient scale so that timing and fuel is adjusted during the warm up time.
- The fans can then be adjusted to come on earlier and keep the coolant and engine room temps cooler.
Downsides are two.
1. Emissions might not meet gov standards.
2. Heater performance is diminished.
btw there is a rule of thumb for cooling. 20% of the heat produced goes into the air surrounding the engine, 40% goes out the tailpipe, 40% goes into the cooling system.
Last edited by wydopnthrtl; Apr 19, 2020 at 07:52 AM.
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Interesting, I never knew about the 20%, 40%, 40% rule.
Yes, I'd replace the coolant expansion tank while you are doing the job. The plastic tank gets brittle over time and usually starts leaking at the nipple. They are cheap. I'd also go with a new cap, get the 18 psi one.
Yes, I'd replace the coolant expansion tank while you are doing the job. The plastic tank gets brittle over time and usually starts leaking at the nipple. They are cheap. I'd also go with a new cap, get the 18 psi one.
