AHHHHH

Car runs around 212-215 while on highway and gets into upper 230's when driving around 35-40 mph. But when I come to a stop and both fans kick on high, the temp starts to drop.

I have 160 thermostat, Lt1 radiator, spal extreme 16" fan (3000 cfm), and 8" spal fan.

I am running 60% water and 40% antifreeze and a bottle of hyperlube. I have bled system multiple times and can't get anymore air out.

I guess I need to buy a new thermostat and see of that fixes it.....any other suggestions?

 

are you fans wires correctlY ?

 

How is airflow into the front of your car? Pictures? Sounds like a classic case of restricted airflow, which fans can't really make up for. Does it freeze where you live? You could easily go to pure water (distilled & deionized, easy to get from supermarket) and Redline Water Wetter (or hyperlube, don't know it) for the summer. Pure water cools a lot better than antifreeze. Make sure you bleed your cooling system with the heat on high in the car and the car warmed up. Test your thermostat easily with a cheap candy thermometer and a pot of water - put the heat on and watch the stat open around 160, turn the heat off, watch it slowly close. As he said above, make sure you fans are moving air in the right direction.

Jim

 

yea it sounds like a blocked radiator, or your fans arent kicking to high setting soon enough. they should be on high well before 230 degrees. might want to check your fan settings and check for blockages. also could be a thermostat sticking possibly.

 

This is why I got out of the FI game. I just got tired of chasing problems.

 

are you running both an upper and lower radiator shroud?

 

Wouldn't 100% water also boil sooner too? Doesn't sound like a good idea to me

Also, is the AC on when you are overheating? If so, when you turn it off, how hot does it get?

 

If you have modified/removed the stock shrouds/air dam you will have problems. My "fix" was to try to make some type of shroud and air dam, so the air is directed to the radiator.
Something else that I tried was having my fans controlled by BS3, so that way they aren't turning off once the car reaches a certain MPH like they do with the stock PCM. It seemed to help. Only problem with that is that they require alot of amps to run and thats not a good thing when the car is going WOT and other things require lots of amperage as well.

 

100% water is way better for cooling than a mix,just sucks to change when temp is less than 32F.

 

Whats gonna stop the water from boiling tho?

 

Yes fans pull through radiator

High fans kick on at 204, low kicks on at 194

Yes, I have the plastic shrouds and air dam on the car

A/c was off



I am going to check thermostat in the morning

 

The boiling point of water goes up under pressure, so your typical pressurized system helps that. Throw in generous airflow and an properly-plumbed overflow/drainback tank and you should be set. The Water Wetter is a surfectant like soap which prevents bubbles from forming by reducing the coolant's surface tension, and can help prevent localized hot spots and steam pockets.

But the best coolant in the world will not make up for poor airflow, and airflow doesn't just mean exposure of one side to the air, the air has to have someplace to go after it absorbs its bit of heat, too. I've seen setups that look like they would flow killer until you see them almost completely blocked at the rear by a crossmember and motor stuff.

Pictures of your setup (front and rear of rad) would help here.

I would turn on the low fans at 175 and high at 190, see what happens.

Jim

 

Agree with all of the above.

There is essentially no free flow of air to the radiator with the system as it is designed. All air flow that reaches the radiator has to go through the AC condenser first. So parked or in slow moving traffic you essentially have no air flow.

As a test to prove my theory I removed my Becool radiator and installed a new SLP 97 style radiator I had purchased prior to the install of the Becool. I have an ATI DISC and have been experiencing overheating from the get-go.

I also installed two 12 inch pusher fans (about 1800 cfm) on the front side of the AC condensor. Both come on when I start the car. I also removed the plastic AC condenser shrouds aft the hood latch and in front of the AC condenser.

I have driven the car this week in some very hot Kansas weather (90's). So far the temp has not reached 225 or higher (98 temp gauge).

Yesterday after a 5 mile highway cruise at 70, I parked the car in my driveway in the sun and let it idle for 20 minutes with the AC running at max. When I parked it the temp guage was at 190. Sitting idling with AC on at max it never got over 225.

Performing the same test with the Becool before the installation of the two fans - the temp has pegged on the red mark on the temp guage.

With the Becool I was not able to drive in traffic with AC on either. The temp would climb to over 230 and eventually peg at the red mark at which point I would have to turn off the AC and turn on the heater.

It defies logic that the smaller stock radiator is maintaining cooler temps than the huge Becool - but it is. And the only thing I can attribute this to is because of better air flow due to the addition of the two pusher fans.

Why? Because they are constantly pushing air through the condenser thereby keeping it cooler while at the same time pushing and assisting the puller fans backside of the radiator to pull more air through the radiator.

Result - the coolant stays at a lower temp while idling and in stop and go traffic.

I'll keep testing for the rest of the summer and if this works then I will replace the two cheaper Hayes fans with better quality and higher capacity Spal or Permacool fans.

The cost to make this fix was less than $130.

Note: As for the Becool radiator. Because it is so thick IMO it actually reduces air flow out of the engine bay. There is hardly any space between the radiator and ATI fan shroud after air exits the rear of the radiator for air to escape out of the engine bay. As a result underhood temps are extreme.

Since the addtion of the two pusher fans I have also noticed that underhood temps are down too. The stock fan and ATI shroud projects nearly 4 inches less into the engine bay compared to the Becool. With the stock fan there is some space for air to exit on the passenger side. The driver side is still blocked by the ATI charger.

I also have an UltraZ hood with a fresh air inlet. It lets some fesh air into the engine bay and I removed the cowl seal so air can escape from the engine bay.

 

i would not run pure water because rust can form inside the radiator.

 

not with distilled and deionized...also its all aluminum block and heads

 

Thermostat looks fine......starts opening right after 160 and looks wide open by mid 170's.......

 

Thanks for the explanation of that DeltaT

dlandsvZ28- Did you try the becool with the shrouds off and pushers on too? If not, sounds like you are comparing apples to oranges...

 

What water pump? I had a failing EWP that whooped my *** for months trying to figure it out. Now my **** runs cool, but I have done everything you can imagine. Aluminum radiator, spal 9", new EWP, etc.

Kick the fans on early, no need to wait till it gets hot. Mine comes on at 16x and doesn't shut off. I run the 9" on a switch, I can keep the car well under 200 in the heat with a 408.

 

stock water pump....I am going to flush radiator and bleed it again and see what happens

also, kicking fans on earlier won't help temp when driving down highway at 70mph.....so there is another problem

 

This makes perfect sense, a tighter fin count on the radiator such as the Be Cools or Ron Davis units will reduce air flow through the radiator. Sure they will dissipate more heat, but they won't keep the car cool if there is not enough airflow through the core. The F-Bosy is just a handicap in this regards. I think the real key is airflow (pusher and puller fans)

It would have been interesting to see the same fan set-up on the Be Cool radiator.

The OP's issue sounds like a coolant flow problem (pump or radiator) un-related to airflow from what is described, that is if the problem just cropped up. If it is only related to higher outside temperatures it may be an issue of being undersized on the radiator core.