454 Coolant Temp - What should it run

[Gorgi S.]

Seen several discussions on this and my main question is what should a 1972 454ci coolant temperature be at with normal driving.

I know this question will get mixed response but in general most cars are setup with a temp range (usually based on thermostat) that they will run between. Seems like the 72 454 is 160-200 in normal driving at 60s-70s outside temp.

Reason I ask is when I bought the car 15years ago it was late Oct (in the 30's) and when I drove it home it ran great and stayed below the 200 mark on the guage. A few summers ago, and since I only was driving in summer I switched from a 180 thermstat to 160 because the car was running closer or over 200 in 90degree plus outside temp. The 160 got me back below 200 on nost hot days.

I have not driven the car in cold weather (anything below 50) in a long time and I just took it out over the weekend (30's outside) because I had to switch garages and the car stayed below 160 while driving and just over 160 when parked (IR verified). Also the car just did not run that great.

I figure the reason is because I put the 160 thermostat in there and now the car wants to run closer to that mark vs the 180.

Since I don't plan on doing much winter driving I'm leaving the 160 in the car but

was wondering if anyone knew the temperature range that the 454 was designed to run at?

[Joe L.]

Re: 454 Coolant Temp - What should it run

Seen several discussions on this and my main question is what should a 1972 454ci coolant temperature be at with normal driving.

I know this question will get mixed response but in general most cars are setup with a temp range (usually based on thermostat) that they will run between. Seems like the 72 454 is 160-200 in normal driving at 60s-70s outside temp.

Reason I ask is when I bought the car 15years ago it was late Oct (in the 30's) and when I drove it home it ran great and stayed below the 200 mark on the guage. A few summers ago, and since I only was driving in summer I switched from a 180 thermstat to 160 because the car was running closer or over 200 in 90degree plus outside temp. The 160 got me back below 200 on nost hot days.

I have not driven the car in cold weather (anything below 50) in a long time and I just took it out over the weekend (30's outside) because I had to switch garages and the car stayed below 160 while driving and just over 160 when parked (IR verified). Also the car just did not run that great.

I figure the reason is because I put the 160 thermostat in there and now the car wants to run closer to that mark vs the 180.

Since I don't plan on doing much winter driving I'm leaving the 160 in the car but

was wondering if anyone knew the temperature range that the 454 was designed to run at?

Gorgi------


I'm surprised that the 160 degree thermostat did you any good. A thermostat only controls the LOWEST temperature that an engine will operate at (after warm-up). Actually, I don't recommend the use of a 160 degree thermostat under any circumstances. Using one can cause too wide a temperature swing under certain operating conditions.

For the most part, I would expect your engine to operate in the 180-210 degree range. In very hot ambient temperatures and/or extended idling/slow traffic and/or long uphill grades, the temperature might even get a little above 210.

For the above to apply, your cooling system has to be in good condition. That means a radiator in very good condition, all radiator/shroud seals in place and in good condition, 50/50 coolant mixture, and a properly operating fan clutch. The lack of the latter is the problem that MANY cars suffer from.

[Jim T.]

Re: 454 Coolant Temp - What should it run

Seen several discussions on this and my main question is what should a 1972 454ci coolant temperature be at with normal driving.

I know this question will get mixed response but in general most cars are setup with a temp range (usually based on thermostat) that they will run between. Seems like the 72 454 is 160-200 in normal driving at 60s-70s outside temp.

Reason I ask is when I bought the car 15years ago it was late Oct (in the 30's) and when I drove it home it ran great and stayed below the 200 mark on the guage. A few summers ago, and since I only was driving in summer I switched from a 180 thermstat to 160 because the car was running closer or over 200 in 90degree plus outside temp. The 160 got me back below 200 on nost hot days.

I have not driven the car in cold weather (anything below 50) in a long time and I just took it out over the weekend (30's outside) because I had to switch garages and the car stayed below 160 while driving and just over 160 when parked (IR verified). Also the car just did not run that great.

I figure the reason is because I put the 160 thermostat in there and now the car wants to run closer to that mark vs the 180.

Since I don't plan on doing much winter driving I'm leaving the 160 in the car but

was wondering if anyone knew the temperature range that the 454 was designed to run at?

When your 72 454 was running over 200 and it was 90 degrees plus, was this at a constant speed on the interstate 70-80 mph or was it in city stop and go traffic?

If your 72 has the TCS solenoid controlling when your vacuum advance functions try bypassing the TCS solenoid completely. Connect full time vacuum advance to the distributors vacuum advance. Full time, not ported vacuum advance 100% of the time should provide for a cooler engine temp in city stop and go traffic and better gas mileage.

[Duke W.]

Re: 454 Coolant Temp - What should it run

The OE thermostat is 195F nominal opening temperature, and the normal operating temperature range is 190-230F.

Emission controlled engines are designed to operate in this range!!!

A lower range can be implemented with a 180 degree thermostat and modifying the spark advance map to something approaching the L-36, which would include, as a minimum, replacing the VAC with the L-36 VAC and bypassing the TCS concurrent with a change to full time from ported vacuum advance. It may also require modifying the centrifugal curve for more advance at a quicker rate.

Do some archive research if you want specifics. A 160 degree thermostat on an emission controlled engine with OE spark advance map and control system is a useless crutch.

Duke

[Gorgi S.]

Re: 454 Coolant Temp - What should it run

My cooling system is working great, (using stock rad, new fan clutch, all the shrouds in place, only thing that could be better is the actual fan) I also have disconnected the TCS and timing is correct.

I spent several years getting it to the point where the car will not overheat. The only time I even see the temp climbing high (over 230+) is when I'm idling for a long time (30mins or more) in stop & go on a hot day(Dream Cruise). For this I put a pusher fan in and I'm good.

The car just seemed to be running hot above 210F on 90+ weather just crusing at 40-50mph with no stops. That's why I decided to try a themro swap. Figuring I'd get the system circulating sooner.

When I put the 160 stat into it, I got down below 200 in the same conditions.

If the car is supposed to run 190-230 or 180-210 then even the 160 stat is getting me there, it's just taking longer. I will likely put the 180 back in.

[Jim T.]

Re: 454 Coolant Temp - What should it run

My cooling system is working great, (using stock rad, new fan clutch, all the shrouds in place, only thing that could be better is the actual fan) I also have disconnected the TCS and timing is correct.

I spent several years getting it to the point where the car will not overheat. The only time I even see the temp climbing high (over 230+) is when I'm idling for a long time (30mins or more) in stop & go on a hot day(Dream Cruise). For this I put a pusher fan in and I'm good.

The car just seemed to be running hot above 210F on 90+ weather just crusing at 40-50mph with no stops. That's why I decided to try a themro swap. Figuring I'd get the system circulating sooner.

When I put the 160 stat into it, I got down below 200 in the same conditions.

If the car is supposed to run 190-230 or 180-210 then even the 160 stat is getting me there, it's just taking longer. I will likely put the 180 back in.

Gorgi you mentioned that you have disconnected the TCS. After doing this did you connect a vacuum hose to the vacuum advance and to a full time vacuum connection. A ported vacuum advance connection will not give the best vacuum when your car is at idle.

[Michael F.]

Re: 454 Coolant Temp - What should it run

160 degree is too cool. You get possible accelerated engine wear under 180.

[Edward J.]

Re: 454 Coolant Temp - What should it run

Gorgi, Alot of useful info, I would like to add alittle to it all, I would also find that a 160 deg. themostat, may end up being a problem on a car that may have a underline cooiling system problem,( Not saying you have a problem) By using a 160 deg. themostat there maynot be enough time to cool the engine down properly before the themostat opens, and if there was a problem with blockage in the radiator, It may just makes things worst. I would say if the factory themostat was 180 or 195 use what they say, if your living in a hot climate the 180 would be the lowest to go.

200/220 Degrees in traffic situations or not a problem, but crusing speeds should be back in the normal operating range, 180/190.

[Gorgi S.]

Re: 454 Coolant Temp - What should it run

I believe I'm on a full time vac, off the carb, but I may need to check that again as I did do a carb rebuild a few years ago.

I agree 160 is to low but it worked and it was my last straw. I'm use to cars running 180-200 but it seemed like the 454 was always running over 200 on the hot days of summer , when I drive most. Figured there were only 1-2 solution left #1) Al rad, #2) Electric Cooling - was not going to do that since the car mostly original. So I tried the thermostat.

Not sure why it worked but when I drove it last weekend (mind you it was barely above freezing in Mich) it seemed like the temp was tooo low.