Engine Foxbody cooling and idling

Hi guys have a 89 5.0 5 Speed. Had my engine redone. 306 xe274HR cam, qualfast 195cc/68cc chamber heads, 24lb Injextors set at 43PSI, edlebrock upper and lower performer intake, under drive pullies, stock water pump
Trying to iron out some of the issues. I have the 3 row SVE rad and electric fan. It was sufficient on the stock setup. But it does not cool it down now. Thinking of making the switch to either a spal or flex a lite fan. I'm running a Holley Terminator X ecu on the car and I'm noticing the temps on the car are rising to near op temps within about 4-6 mins of idle. Goes from about 70f-175f before it slows down. The car has a 180 degree thermostat in it right now. Today in BC it was about 3C out and car still was warming up at idle really quickly.
My question Is how long is the fox in colder temps suppose to be hearing up?
2. I'd like to switch to a better fan, What are you guys running for fans? I've heard good things about dual SPAL fans and or a single flex a lite black magic 185
Just like some opinions and input
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I have a 3 core copper rad, Contour dual fans (set up to run dual speed) with fan controller sensing water temps in lower rad hose, 180* t-stat and stock water pump. My low speed fan comes on at 203*, high speed (if necessary) comes on at 215* - never gets that hot though.

Engine temps up to 205-210 would be considered normal. Don't forget stock t-stat is 195*.

When you did the engine switch, did you get all air out of the cooling system? What electric fan are you using? How are you controlling it? Sensor location?
It takes quite a while for my car to warm up. I have to drive about a mile, or more to show halfway up the factory gauge. From what you wrote I would check to see if your pump/water is even flowing.
I'm running the sve dual 12 electric fans with there 3 row rad and controller. The fan control temp sensor is in the water neck with a bung and that's is were the Holley reads it temps at. At one point the was one notch away from Max on the dash. When the Holly is reading 200 at the water neck. Dash gauage is reading 1 notch away from balf. The car has a 180 thermostat. The issue I'm having is while driving the fans don't seem to be really cooling and temps just creep more and more.
What is the temperature set point to trigger the fans?

The fan control temp sensor is in the water neck
Do you mean in the t-stat housing? If so, before or after t-stat?

The issue I'm having is while driving the fans don't seem to be really cooling and temps just creep more and more.
Can you manually trigger the fans to know they have not blown a fuse or something?

Do the fans have a shroud?

To be honest, when driving, there should be enough air flow to not need the fans (if you have the lower and side rad deflectors)

Pics always help.
Yes the T stat housing. Fans are triggered to come on at 184 F and shut down 179f. I have a manual switch as well and it confirms they are on. The fans have I shroud. But to test I removed the fans from the shroud and mounted them to the rad with a Hayden kit to free up some real estate. The shroud thaf came with the sve kit covered the whole back side of the rad


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Is the lower air dam still installed on the car ?
This helps with directing airflow while driving.
Not bad advice at all but I haven't had that on my car for 20 years. He also has underdrive pulleys which I'd definitely remove but his issue sounds more involved than either of these. Just my opinion which could in fact be completely wrong! :jester:
OP states just had engine work done, so does this mean the cooling issue has been going on since the
the overhaul was completed.
If so are you sure you've gotten all the air out of the system ?

For what it's worth I've been running a 2 row ebay aluminum radiator , 2000 Intrepid fans controlled by a Flexalite vsc33054 for quite a while.
I've had this set-up on my 302 with various superchargers installed and I now currently run it on my n/a 393w.
I've had good luck with it, the Intrepid fan shroud covers the entire width of the radiator and about 3/4 of the height.
Operating temps on my current 393w run about 190-195.
Re-reading the thread, I have some thoughts/ideas.

With a modified engine, do you have a wideband hooked up. You may be running lean at idle which would cause the rapid warm up. Not an issue, but something to think about with the tune (does the lean condition remain at greater RPMs).

Based on getting temp reading from t-stat housing downstream of t-stat should give accurate reading to your ECU of what coolant temp leaving the engine is. With set points as low as you have them (fans on at 184, off at 179) looks like you want a cold engine. Remember the stock ECU wants engine around 190-195.

So if your fans are actually coming on at 185 (at the engine) and you are still getting hot, then you are either not drawing much air through the rad (by the fans) or coolant is not flowing enough through the rad to be cooled sufficiently. If you open the rad cap and watch as you start up the car, can you see coolant flowing out of the tubes into the rad tank? If not flowing well, you may need a rad flush.

Another thing to look at is, when idling, is the lower rad hose collapsing? This would restrict the overall flow in the system as well. With a stock water pump I wouldn't expect this to be the case, but it can still happen. I know some have a metal coil in the lower rad hose to prevent this collapse. My car does not have one.
I have a wide band. The car at start and ideal jumps 14-15 afr and about 12-13 when driving. At start up the coolant doesnt rmove at all. After about 5 mins the level will drop and you can see the coolant flow then. I have the lower air spoiler. The car doesn't take coolant from. The over flow of that matters.
I used those lisle funnels to bleed the cooling system. Other thought I'm having is a bad rad cap?
The rad on the passenger side is warmer then the driver side when I check with a laser gun
Doesn't look like it's afr realated.
Those funnels usually work pretty well, I've used them to bleed reverse cooled systems with pretty good success.
Having a good radiator cap is a cheap investment , if the current one is suspect I would replace.
When engine work was done was the water pump replaced and if so was it replaced with the correct reverse rotation pump ?
The rad on the passenger side is warmer then the driver side when I check with a laser gun
That would make sense as hot coolant enters on the passenger side of rad, should get cooled as it passed through the rad, so driver side would be cooler.

After about 5 mins the level will drop and you can see the coolant flow then.
That would happen when the t-stat opens, thus starting flow through the system. Once the flow starts and fluid level in rad tank drops, I usually add more coolant, essentially topping up as air continues to burp out through the rad tubes. When coolant stops going down in the tank, you should be good to go. Overflow tank will catch the rest.

Out of curiousity, what were the temps you were seeing with the laser gun (thermo gun).
I have a stupid question. If I'm putting a napkin to the front of the rad should it sick it towards it or blow it forward? When I'm placing a napkin in front of the rad when the fans are on. The napkin is pushing it away and not ducking it into the rad