Acceptable engine temp

[Bleep Bleep]

‘69 road runner 383 bored .060 over and 22” radiator. The 3 gauge cluster temp is reading climbs up to a high of 195-200 after 30 minutes or so of moderate driving - averaging 2300-2400 rpm. It can get a little hotter if I’m pushing it harder.

It then holds steady around just under 200. Creeps up to ~205 in stop and go traffic.

I understand over-bored motors tend to run a bit hotter but want some comfort 200 is not going to do any damage.

For what it’s worth, oem gauge needle reads between first mark and 12 o’clock. So that looks pretty normal I assume.

Thanks!

 

[Jerry Hall]

I think it's safe at 205. I wouldn't push it much higher. Comfort enough?

 

[toolmanmike]

It's not overheating or not really getting hot. 195° thermostat?

 

[dadsbee]

I certainly wouldn't be complaining about 205! Water boils at 212 with no pressure cap.

 

[toolmanmike]

I certainly wouldn't be complaining about 205! Water boils at 212 with no pressure cap.

And every pound of pressure raises the boiling point 3°. A 15# cap raises that 212° to 257° at sea level. The pressure cap, altitude, and coolant mix adjusts those temps but not by much.

 

[Sixpactogo]

You didn't mention it but if you are not running a shroud and thermo clutch 7 blade fan properly installed and the core support to hood seal, those improvements could help drop those temps a bit but other than that, your temps seem to be ball park for a big block.

 

[Doorkicker]

hmmm... interesting responses so far. I start getting uncomfortable at 190°

Here's another thread you might find helpful...

Question on engine temp. How hot is too hot?

I have a 400 bored and stroked to 512. I have a 3 core Aluminum rad with dual 10” pushers and a 18” puller, so lots of air flow to help cool. Perhaps this is a non-issue, but being I have a few $’s in this engine I don’t want to burn it up. I have been concerned because the heat gauge is much...

www.forbbodiesonly.com

 

[dadsbee]

hmmm... interesting responses so far. I start getting uncomfortable at 190°

Here's another thread you might find helpful...

http://[URL]https://www.forbbodieso...tion-on-engine-temp-how-hot-is-too-hot.55307/

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Why? I run 180 or 190 stats in every car. They run just above them, but hot day in traffic they may go to 220. Still don't puke...

 

[Dennis H]

Ambient temperature? Mine to this day doesn’t like extended idle. 440. At sea level and about 70 ambient it can creep. Recently pulled into the carport and just let it run for 15 minutes ac on. Crept to 207, then dropped to 203. 180 Stat. Move off, and it drops. August, Reno, 5k feet it can go to 210 and noticeably unhappy. Shroud, wetter, up you name it it’s been done.

 

[451Mopar]

I don't like over 210-215 F. Sort of a warning at those temps, and I will pull over and stop if it get to 230 F.

 

[MWbirdLOVER70]

‘69 road runner 383 bored .060 over and 22” radiator. The 3 gauge cluster temp is reading climbs up to a high of 195-200 after 30 minutes or so of moderate driving - averaging 2300-2400 rpm. It can get a little hotter if I’m pushing it harder.

It then holds steady around just under 200. Creeps up to ~205 in stop and go traffic.

I understand over-bored motors tend to run a bit hotter but want some comfort 200 is not going to do any damage.

For what it’s worth, oem gauge needle reads between first mark and 12 o’clock. So that looks pretty normal I assume.

Thanks!

I had a 2 row 22’ and had shop go to 3 row and 170-180 now. 383 30 over and 11.5 compression

 

[PurpleBeeper]

‘69 road runner 383 bored .060 over and 22” radiator. The 3 gauge cluster temp is reading climbs up to a high of 195-200 after 30 minutes or so of moderate driving - averaging 2300-2400 rpm. It can get a little hotter if I’m pushing it harder.

It then holds steady around just under 200. Creeps up to ~205 in stop and go traffic.

I understand over-bored motors tend to run a bit hotter but want some comfort 200 is not going to do any damage.

For what it’s worth, oem gauge needle reads between first mark and 12 o’clock. So that looks pretty normal I assume.

Thanks!

I’d say you are borderline ok.

 

[Dennis H]

I’d say you are borderline ok.

You mean RJ?

 

[WileE]

Don't forget, in order to satisfy emissions requirements back in the day, the automakers used 195deg thermostats. So your operating range is fine.

 

[cosgig]

I run a 195 thermostat, the recommended thermostat for my car. Never goes above that. There’s nothing wrong with 200 temp, big block Mopars like to run a little hot.

 

[Bleep Bleep]

Thanks for the input everybody. New car to me so I don’t know what temp thermostat. Does the cap indicate what #pressure the cap is?

 

[oldbee]

Yes it should. My recommendation is 13# for cap. Little less pressure is good for the hoses.

 

[Bleep Bleep]

Yes it should. My recommendation is 13# for cap. Little less pressure is good for the hoses.

Thanks!

 

[Tony Tee]

If your temperature keeps climbing up in slow traffic. Or when you are stomping on the gas. You don't have enough cooling capacity.
Get a better radiator or waterpump. My vehicles get up to temperature and stay there. And i live in Florida. Can you drive it like roscoe or Steve McQueen is chasing you? with not having to constantly look at the temp gauge? Just my opinion.

 

[WileE]

If you're concerned, Perhaps get the radiator boiled out and rodded, to restore it to original efficiency. A common job we had back in the garage, once done, vehicle back to operating as usual. If not already equipped, I'd recommend a shroud.