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26 Posts
Discussion Starter · #1 ·
my 454 likes to sit around 210 degrees until I idle at a red light for 2 minutes in traffic and it creeps up to 230.

I want to get her down in the 180 - 190 range and I'm going to add a shroud and likely a better radiator, but I have a feeling the culprit may be timing as well. I haven't messed with timing before, and I've got a case of beer in it for anyone who wants to meet up and help me out in the LA / San fernando valley area.

· Registered
9,084 Posts
Hi guys,yup,a fan shroud with proper fan and spacing is a MUST ,that's for sure.

My 69 with mild perf bbc /4spd/331's /4 core rad/772 7 blade cluch fan and HD fan clutch run just where you want,180-185deg @ cruise & 190 deg on hot days at cruise,190-195 deg when in traffic in warm but not real hot days and on hotter HHH days @ 85-90+ deg 200 deg max when in traffic for approx 10-15mins on hot days.


* are you running a 180 deg stat?

* Is temp gauge mech type with temp sender in head by ex port that typically reads 10-15 deg hotter then if itsin the intake?

* If running temp sender in head with metal cable is it insulated from from excessive ex haet from head to firewall ? If not that can heat soak the metal calbe in traffic wich can falsely increase temps by 6-10 deg at times depending on setup.

* are you running a hi flow water punp or a stocker?

* is coolent mix 50/50 or approx 30% coloent/70% water?

* what fan setup are you running?

* If running a fan clutch is it std duty or HD that does a considerably better cooling job with bbc in traffic?

* Is idle mixture set correctly which can add to cooling issues at idle if set too lean?

* are you running enough octane for setup?

*How old is the radiator and is it 2/3/or 4 core?

* if running auto trans is there a external trans cooler in front of rad bloking considerable fresh/cool airflow?

*Are you running avc adv and if yes is it hooked to full int vac all the time or ported vac with no vac for vac adv at idle ? No vac adv esp at idle or when at lower engine speeds can in some cases cause increase in idle temp.

* Timing,since its built as you put it in your sig whats base & total timing?

To start with running a perf cam,16-18 base + 20 deg mech in dist for 36-38 total with vac adv thats fully activated at idle & gives max of 12-14 deg additonal timing .

Base timing gets set with vac adv unhooked & pluged along with ildle low like 600-650rpms max to keep mech adv in dist from partially activating when setting base timng messing it up.

I guess thats enough for you work on/chk out for a while/LOL!!!!!

Let us know how all that chks out and what if anything you try decreses the temp and by how much for us to all learn from with your experience.


· Registered
26 Posts
Discussion Starter · #4 ·
When I say built 454, I mean mildly. its a 1974 2 bolt main that's been put together for street use. Race heads, bored .30 over to make sure everything fits nicely, new pistons, mild cam, etc. Nothing that'll call for race fuel but enough to get me into a considerable amount of trouble.

I have maybe 500 miles on it so everything is just wearing in, perhaps creating a little more heat?

I'm running a 190 T-stat.

There may be some sort of play in the gauge because a few minutes after shut down it'll read 250, but no water / coolant mixture boils out of the collector (though it does fill past full).

coolant mixture is probably closer to 30 / 70

fan is 7 blade steel, no shroud. I have NO idea if the fan clutch is heavy duty or not (how do I find out?)

I'm running 91 octane, and that is definitely enough.

I'm not running lean.

Radiator is about 4 years old and is a 3 core.

Trans is a muncie 4 speed so no trans cooler.

I haven't the mechanical expertise or know-how to tell you the rest, I just recently picked this car up and am sorting it out while using it as a learning experience. I've never fussed around with timing and could definitely use some help in this area and the avc advance and vacuum.

also, since you guys are so helpful, my idle is high until I blip the throttle. gets sort of annoying at every single light. what should i be checking out?

· Registered
94 Posts
I had the same problem with mine and ended up with a 160* thermostat and now it stays right around 180 until I get into traffic, then its up around 210. I do have a shroud, 4 core radiator and flex fan, but also have small dual trans coolers on the front of the radiator.
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