Cooling for my V8

[DrC]

Last week at Beaver Run I had some heat issue since I removed the heater unit in my 95 Mustang.

Most of the cooking system is Stock,

 

My questions are :

Is it better to run with no thermostat or run with one rated at 165?

If free flowing does the liquid have time to dissipate the heat from the motor and the radiator?

 

Which does a better job Cooling?

- Water and antifreeze

- Water and say Red Line Water Wetter?

[nape1548534725]

I run a thermostat so that the car will come up to temp faster on the colder April/October events.

 

The biggest problem with running hot is not ducting air through the radiator. Whichever way you are picking up air needs to have a sealed box to the radiator so that the air has to go through it, not around/underneath/above.

 

With a proper duct and radiator air deflector, I could push the car 10/10 with a stock radiator in my AI car (~300RWHP) and it would run 230* in clean air and 240* in traffic on a high 80* day.

 

I know a certain CMC2 Firebird still running the stock radiator, but ducting is key.

 

Also, if the radiator has never been out and sprayed inside and out to clean out the gunk, that can also cause it to run hotter then necessary. Water Wetter will help vs. straight water and I would figure out your setup based on that. No antifreeze allowed in race classes, so it's time to figure out how to do without it.

[Trevor571548534737]

I have no heater core stuff inside, and have had no problems with all stock parts, with an aluminum radiator. In fact I have no idea what the temp rating of the thermostat is, or what pressure my cap is rated at.

[92MNstanger]

Removing the cooking system should cool things down.

 

On my old AI mustang, I took off the front clip and built a box around the radiator and put it back together. You can do this on a CMC legal car without too much exense/effort and no cutting of the stock core support.

 

 

On the CMC car, I used water pipe insulation along side the radiator to seal it off as TJ suggested.

[RichV]

OK, read my story. I just finished the biggest headache with my 'heating system' as you call it.

 

89 Mustang, stock water pump, big aluminum radiator (3 core), no thermostat no heater. Electric fan with thermo switch.

 

Car has allways run a little hot, maybe 210-230 coming off the track. At a track event before 2010 Hallett I noticed temps in the 240+ range after a couple of laps. Concerned I kept tracktime minimal that day, got home did a complete flush, water wetter, had it fired up in the garage and was able to maintain whatever I set the electric fan controller to.

 

Hallett 2010, morning session was fine, came off the track 220-230, thought it was OK. Next session, back in the 240-250 range. Getting nervous. Boxed the front end as much as I could with cardboard and aluminum tape. Spoke to M.Mosty and was told to extend the lower chin spoiler under the radiator support. Got some hard plastic material and attached it to the small stock unit. Helped, but the last Sunday race temps were still 250ish, so I was just hoping I did not hurt the motor.

 

Last weekend at PPIR, did another big flush, watter wetter, anti rust additive, higher pressure radiator cap. Ran cooler in the morning session, but again hot later in the day. Ran the Saturday race at 250, didn't let up because I was running in 2nd place . Sunday I thought I'd try something with that lower chin spoiler extension because my thought was it was folding under the car at speed. This was it. I made some temporary supports and in the 30 minute afternoon race #71 did not get above 200 degrees!!! What a difference!!

 

 

You can see my tape supports under the nose.

[KiMifan]

My SN95 never ran over 200 degrees, and that was idling in the paddock with no fan (never installed one). On track, it rarely went over 190, and on cool mornings was often close to too cool (150-170). Building ductwork out of airdam plastic to direct all air through the radiator along with the lower spoiler are key, as well as a good radiator. Make sure you seal off the top of the radiator along the core support and the sides behind the bumper cover. I always ran a stock Ford pump and a 160 degree T-stat with straight water and some water pump lube just to cut down on corrosion.

[Redding CMCer]

Rich; If you seal off the engine compartment, i.e. no holes that could let air in or out...will help with cooling also. I didn't believe that would make a big difference until I had that problem and Brady's dad told me to try sealing up the engine compartment and my car never has run hot since. I just used duct tape to seal the holes at the track and that was good enough. You are correct about the low spoiler...That is another key to cooling. It creates a vacuum in the engine bay that draws the air through the radiator. Gary

[liebbe1548534713]

Regarding low chin spoilers, make sure they are above the minimum height rule. These were checked in Texas last year or the year before. I'm assuming the rule still stands but haven't checked it lately.

 

Here it is from the 2010 CMC Rules

 

 

7.5.5 No body component with the exception of the radiator air deflector shall be lower than 4†measured

vertically from the ground. Radiator air deflectors shall be no lower than 2 inches measured vertically from

the ground.

[mitchntx1548534714]

Be careful putting bracing on the back side. Go agricultural, bend them back and you very well could be below legal height limits. Been there, done that.

 

Now, I have a 1/16" stranded cable attached to the chin and forward to the bumper cover mount.

[BADVENM]

Got me digging through the rules when I saw the picture Rich...you're good (legal)

 

As long as it doesnt make you go faster

[TurboShortBus]

Is it better to run with no thermostat or run with one rated at 165?

If free flowing does the liquid have time to dissipate the heat from the motor and the radiator?

My brother runs his Factory Five Challenge car sans thermostat (primarily because it's "one less part to fail") and sans fan (although the radiator isn't a stock-style Mustang unit) and has no cooling problems unless the car idles for too long on the grid, which is understandable.

 

I have no specific temperature data to offer, but my mostly stock 2004 GT (235 rwhp, all HVAC removed, no ducting other than the OEM chin deflector) may or may not have the OEM electric fan running by the time I get back to my pit after a 25 minute session. In hotter weather during the summer, even if the fan is running when I get to my pit stall, it will cycle on and off as it idles. I believe that the ECU has been reprogrammed to have the fan turn on sooner (somewhere in the 190*F range, if memory serves me correctly), but I am still using the original thermostat that came with the car.

 

Are you still using the original 1995 radiator, or have you replaced/upgraded it lately? If it's the former, then there could be years of mung in there that could be hindering flow.

 

Mark

[TurboShortBus]

Which does a better job Cooling?

- Water and antifreeze

- Water and say Red Line Water Wetter?

Use water and Water Wetter, because:

 

15.18 Engine Coolant

Ethylene Glycol-based antifreeze and other additives that may cause a slippery condition if spilled on track are prohibited. Other water additives such as Redline Water Wetter may be used.

Mark

[DrC]

I will be going to the water and Water Wetter after the winter and hope to take the Comp Class first thing next year.

 

I would like to see some pictures of what you have done to channel the air flow to get the best results. I am doing all the work myself so I am relying a lot of your failures and mostly your successes. You guy down in TX I know have beat the heat with the temperatures there.

 

So far I have removed the Thermostat due the the current temperatures. For next year I will go with the water and Water Wetter and 160 degree .

Now I need to look at the Air flow around the radiator which is a new stock. Did not have a heat issue until I remove the Heater core. My Radiator cap is rated at 16lb.

 

I am going to get the car up in the air and take picture of what I have, At this pint I have little or no Air Dam on the bottom.

 

Was doing some reading and found this – is it legal?Bronco II or Ford Ranger Air Dam

This is the air dam fresh out of the plastic package from the Ford Dealership (Ford Part Number: E3TZ-10001A06-B). Some modifications were necessary to fit it under a Fox3 or SN95 Mustang and still have a factory appearance.

 

Thanks everyone for your help.

[CMC#11]

Dan, putting an air dam on will help big time, an easy 30-40 degrees.

Here is a link to a the Ranger air dam I use.

http://www.chuckbrazeau.com/mustang/airdam.htm

 

I also run a 20 lb. thermostat.

This with a boxed in radiator should cure any problem.

[DrC]

That was the site I was reading, and I found another note on a different site that it would also work on my can. As long as it is Legal that is the way I will go.

[mitchntx1548534714]

I also run a 20 lb. thermostat.

 

Is that so you can make weight?

 

I bet you mean a 20psi radiator cap. Whats the rule of thumb ... 1pound of pressure equal 3 degrees elevated boiling point, at sea level?

 

I would take whatever cap you have to a radiator shop and have them tested. Most I've gotten are 2-4psi below rating. I have a rated 24psi cap on my car because it tested at 21psi.

[KiMifan]

Did not have a heat issue until I remove the Heater core.

 

There's a clue. What method did you use to remove the heater core? It's possible you introduced an air pocket into the system somehow. Did you maintain the bypass hose from the water pump to the T-stat housing? The best way to rework the cooling system routing on a 5.0L is to completely remove the heater manifold from the intake, remove the second hose bung in the pump (which needs to be pressed or drilled out), then drill and tap the hole and plug it with a 1/2NPT plug. It takes a little work to do this but it results in a cleaner, simpler setup with fewer potential leak passages.

[cmc35]

Dan - I use the same Ranger air dam on my '94 Mustang. Works just fine.

 

-chris

[CMC#11]

I also run a 20 lb. thermostat.

 

Is that so you can make weight?

 

I bet you mean a 20psi radiator cap.

Oops, yea radiator cap.

[BADVENM]

Dan - I use the same Ranger air dam on my '94 Mustang. Works just fine.

 

-chris

 

Sweet, Chris' secret weapon is finally revealed!

 

Its on my list of things for next year.

[Redding CMCer]

In response to TurboShortBus' brother's thing about not running a thermostat because it is one less thing to fail...I drilled a couple of 3/8" holes in the one I use. This allows the thermostat to work plus slowing the water down so the radiator can do it's job. I tried no thermostat and the water/water-wetter still got hot. Slowing the flow down helped as well as the things I described in my earlier post. Gary

[DrC]

That was the question on my first post:

If free flowing does the liquid have time to dissipate the heat from the motor and the radiator?

 

The Part is on order and should be here in time for Mid Ohio.

I will show some before and after pictures and the results.

[TurboShortBus]

This should tell you everything you need to know. Pay particular attention to the paragraph below the picture of the thermostat.

 

http://www.stewartcomponents.com/tech_tips/Tech_Tips_3.htm

 

We strongly recommend NEVER using a restrictor: they decrease coolant flow and ultimately inhibit cooling.

A common misconception is that if coolant flows too quickly through the system, that it will not have time to cool properly. However the cooling system is a closed loop, so if you are keeping the coolant in the radiator longer to allow it to cool, you are also allowing it to stay in the engine longer, which increases coolant temperatures. Coolant in the engine will actually boil away from critical heat areas within the cooling system if not forced through the cooling system at a sufficiently high velocity. This situation is a common cause of so-called "hot spots", which can lead to failures.

 

If you are running without a thermostat and the coolant is getting too hot, then your problem is elsewhere.

 

To completely eliminate "air pockets" in a 302, remove the coolant temp sensor from the driver's front corner of the lower manifold (I'm presuming EFI here), pour coolant into the radiator until the coolant reaches the bottom of the sensor threads in the manifold, reinstall the sensor, then top off the radiator and puke tank. Start car and drive.

 

Again, which radiator are you using, and how old is it?

 

Mark

[Glenn]

Just an FYI here, you cannot run an LT1 w/out a thermostat. Due to is design you will have a major flow issue.

[Adam Ginsberg]

I would take whatever cap you have to a radiator shop and have them tested. Most I've gotten are 2-4psi below rating. I have a rated 24psi cap on my car because it tested at 21psi.

 

Mitch is spot on - test your radiator caps. I bought a coolant pressure tester a few years ago (Stant 12270) when I was trying to diagnose an issue, and it's been worth every penny I spent on it. It ALWAYS goes with me to the track.

 

I've had caps fail during a race before, causing wild temp swings (it's happened more than once). At Buttonwillow last year, I lost BOTH caps during a race, and thought I'd blown a HG. Once things cooled down, I realized it was only a set of bad caps.

 

FWIW - on a Mustang, get a ~24psi cap. Mid-90's MBZ 190 sedans used the same cap, rated @ 24psi. When you walk into the parts store to buy some (never buy one, always buy 2 or 3 for spares), test them right infront of the parts guy. For every 5 I test, ~2 or more don't work correctly. They either don't hold ANY pressure, or they hold ~20% (or higher) less than they are supposed to.

 

Remember the old saying - "Just because it's new doesn't mean it's good".

 

To completely eliminate "air pockets" in a 302, remove the coolant temp sensor from the driver's front corner of the lower manifold (I'm presuming EFI here), pour coolant into the radiator until the coolant reaches the bottom of the sensor threads in the manifold, reinstall the sensor, then top off the radiator and puke tank. Start car and drive.

 

You can also install a second cap in the upper radiator hose using an inline filler neck (for a pushrod 302). This allows you to fill the coolant system at the highest point, and helps eliminate the airpockets Mark mentioned.