New AMC 360 Installed - couple questions

[JR74CJ5]

Sure - no harm in that. I’ll post some up tomorrow

 

[lowcountry]

So restricting flow until in-block temp is higher before introducing cooler fluids into it doesn't help with warm ups, or maintaining warmer operating temps in cold climates?

https://auto.howstuffworks.com/how-does-the-thermostat-in-a-cars-cooling-system-work.htm

https://auto.howstuffworks.com/cooling-system8.htm

And some of the hottest climates run no thermostats right? Why when a higher temp one would help keep their engines cooler? I'm not sure this is the most efficient idea (no thermo) but it's been done quite a bit.

Again, not arguing, looking for schooling there. I'm really only wondering how the increased temp rating of the thermostat would assist in maintaining a lower over-all operating temp. If what you said above was true completely, I'd just want a lower thermostat rating, all things otherwise considered...

Yes, getting the temperature up as quickly as possible is a good thing. That is just one benefit of a thermostat. Even more important, is making sure the temperature is not too cold or too hot. This is what a thermostat does. After completely opening, it will start to close as the temperature falls back down. It will continue to cycle this way to maintain the temperature in a specific 'range'. It is not smart enough or efficient enough to maintain an 'exact' constant temperature throughout the entire engine. Engine temperatures can vary significantly from one area to the other.

I'll throw one other wrench in this discussion by saying that from a thermodynamics point of view, the wider the difference is between the ambient temperature and the internal temperature of the engine, the more efficient the engine is. This of course has a limit, but theoretically speaking...

The higher temperatures also help to burn off unwanted chemicals/deposits.

Years ago, common thermostats were 160-180. Thinking has changed. Most engines now run higher than that. My 2015 Silverado runs 210+ all day long...

 

[Lumpy Grits]

LG

 

[JR74CJ5]

Thanks lowcountry - appreciate the follow up.

Hoping to do some work on this tonight and get some vac gauge readings / tuning done. Will be looking at getting that shroud back in, swapping the temp sending unit / probe swapped over from old intake to new one, and taking some IR readings in different areas for actual numbers.

May look into getting a 190 thermostat later but want to take the time to check out tuning, etc first to see if my problem is elsewhere.

Does excessively advanced timing add a factor in for additional heat? Is 14 degree initial advance "excessive"?

I'll post some findings tomorrow (as long as I don't get lazy in the afternoon heat again... lol )

 

[Lumpy Grits]

Yes-on the advanced timing and heat issue.
What's OEM timing for that engine?
You running premium, or regular grade gasoline?
LG

 

[JR74CJ5]

I don't think OEM timing matters as the distributor swap changed that... I think it was 5 or 7? I'd have to check... DUI recommends 12 degrees advanced, the engine, cam upgrade, and tuning I did last night seems like 16 degrees is the best for vac reading and smooth running, starting, and idle / acceleration.

Fun regular - not plus or supreme octane.

The vac gauge reads 17 when I finished tuning @ idle 760-780 rpm. Climbs up to 20 when around 2k RPM hold.

Found a vac leak where the old heat tube connected to the choke on the carb. Plugged it.

Can't install the shroud. Between the 1" body lift, and the engine sitting a bit lower in the front from raising the trans and transfer case up to belly, the shroud will not fit even with heavy modification above the lower radiator hose and fan still clear the inner edge. The radiator would need to be dropped, but I'm not sure it will drop enough with the power steering box lines there. So for now, staying with no shroud.

Swapped the temp probe with the one I had on the 304 instead of the one that came with the new intake off another parts 304 I bought. Temp is staying @ or below 210 degrees now like it did with old 304. Didn't check with the IR gun yet, but seems to be doing fine.

Starts with simple key bump turn (very quick fire) and runs great with no detonation I can hear, even with regular octane level fuel.

Oil pressure higher than it used to be, and maintains even @ idle a bit higher than before.

All in all - she's running very smooth and great now. The idle still has a slight shake, but I did put in a upgraded cam too (lost the details on it right this second...)

All in all good steps forward.

Plan to look into a custom shroud / radiator drop, throwing in a 190 degree thermostat later, and keeping a eye on the actual temp and measuring accuracy of the gauge moving forward.

 

[Lumpy Grits]

At the next fill-up-Get premium gas.
I had similar shroud/radiator clearance issues after my 1" body lift.
Re-drilled the rad. mounting holes to lower the radiator, and did the same for the shroud. Well worth the effort.
What is your ASL altitude where you live?
What is the vacuum reading now, after the leak fix? How much 'needle-dance' do you see on the vacuum gauge?
Hope you are keeping a log book of this, for future reference when CRS creeps in. :laugh:

LG