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hood vents.

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My boss is now 2 days old,when I lifted the hood I noticed the underhood insulation covers most of the vents. Has anybody cut or removed some insulation to make the vents work better?
 
I saw that on a 5.0 that was in my dealers showroom. I figured they designed them that way to direct either the water away from an area or to assist the airflow out of the hood. I would find out the design intent before trimming it away. The engineers don't just do things haphazardly. There has to be a reason. I will be on track this weekend with a Ford engineer that has a 2013 LS and will ask him if he knows.
 
cloud9 said:
I saw that on a 5.0 that was in my dealers showroom. I figured they designed them that way to direct either the water away from an area or to assist the airflow out of the hood. I would find out the design intent before trimming it away. The engineers don't just do things haphazardly. There has to be a reason. I will be on track this weekend with a Ford engineer that has a 2013 LS and will ask him if he knows.

I dont think it to HELP air flow at all. I would guess they dont want the rain running on the motor.
 
jeepinocala said:
cloud9 said:
I saw that on a 5.0 that was in my dealers showroom. I figured they designed them that way to direct either the water away from an area or to assist the airflow out of the hood. I would find out the design intent before trimming it away. The engineers don't just do things haphazardly. There has to be a reason. I will be on track this weekend with a Ford engineer that has a 2013 LS and will ask him if he knows.

I dont think it to HELP air flow at all. I would guess they dont want the rain running on the motor.
Is that opinion based on the wind tunnel testing?
 
It seems to me that the addition of the hood louvers was not just a styling exercise. They made them functional. If they needed to be larger, that would have been done since it would have been no more expensive and would have had no net effect on the styling.

The fact that they chose to deflect water entering the louvers from directly pouring onto the coil covers was no accident. Routine exposure to direct water flow increases the rate of deterioration of electrical and metallic components. So here is a little example I just had with our BMW 740i: The gasket failed on the driver's side windshield washer nossle and was letting a small amount of water through directly onto the coil cover. Probably for years. The car was generally garaged, but a daily driver. The water worked it's way into the coil pack recess, collected around the coils and eventually corroded them and shorted two of them out. There was never any visible evidence of the leak or the damage until the engine began to misfire. The corrosion and shorting eroded the ground connection point on the valve cover requiring repair to that as well.

While Ford added hood louvers to the '13's, they are not nearly as large as the racing hoods. I would bet they help address a cooling concern in severe everyday use, but are only a small improvement to track cooling. If you track your car and it does not get wet (garaged or covered in wet weather, not driven in the rain) then the deflection for the louvers could be removed with no issue and might marginally increase the air flow out the louvers by straightening the path. It will never evacuate the underhood heat like the racing hoods do. Serious track cars probably need all of the factory mods used on their race cars (air to oil cooler, radiator, grill, louvered hood, etc.). For street use I doubt removing the louver deflectors would show any noticeable effect, but would expose the area of coil covers to water effects.

My '12 LS will show 220 in stop and go traffic, especially in summer heat with AC on. I am progressively addressing that in the order: 302s grill (done), Fluidyne radiator (on hand), then real oil cooler and racing louvered hood as required. I want the street temps at or under 200 at all times. If (when) I track the car, I'd accept 220 max. I noticed the LS I drove at the Boss Track Attack ran at 220 in mid 80's weather. It had all the mods I'm planning except the hood. If I had a '13, I'd be pretty confident I wouldn't need the racing hood to meet my objectives.

Mike
 
BossDuke said:
My '12 LS will show 220 in stop and go traffic, especially in summer heat with AC on. I am progressively addressing that in the order: 302s grill (done), Fluidyne radiator (on hand), then real oil cooler and racing louvered hood as required. I want the street temps at or under 200 at all times. If (when) I track the car, I'd accept 220 max. I noticed the LS I drove at the Boss Track Attack ran at 220 in mid 80's weather. It had all the mods I'm planning except the hood. If I had a '13, I'd be pretty confident I wouldn't need the racing hood to meet my objectives.

Mike
I'll be surprised if you can achieve that if you're really pushing the car to its limits on track. If you do, let me in on the secret. I have the following cooling mods:

302S grille
302S air-to-oil cooler
302S radiator
302S Tiger Racing hood
1 bottle Water Wetter

In 80s* ambient temps, I push coolant temps in the mid to upper 240s. In 90+ I have to remove my grille to keep it below 250, but have seen it as high as 255*. My oil tops out at around 235*. I have also driven LSs on track in 90* ambient and seen upper 240s on the water temps. This is on tracks between 1000 and 2000 ft above sea level.
 
220 in everyday driving? Yikes! I rarely see over 200 in mine driving around town and with my CJ grille I haven't seen over 220 at the track. I'm sure you guys are pushing harder than me but 220 on the street seems really high.
 
He said stop and go with the AC on (is out AC electric? I never even looked). I'd believe it, but I doubt any venting would help as the air will not be moving anyways other than the fan which should be able to vent enough anyways. On our ranch Jeep, the tranny would overheat constantly due to crawling in high heat at altitude, and adding a good sized oil cooler for the trans helped a lot. We were getting constant CTLs (check tranny light, they added those due to the common issue) before and have not gotten one since. So for stop and go, from my experience, I would suggest larger cooling surface rather than improved venting. At speed, the venting would probably be more useful. Though I have not talked to anyone at the track who has really solved the issues. I still think a water spray system for the radiator would be either a cure or at least a big improvement, based on dealing with heat soak in intercoolers, and there are some fairly easy home built solutions that I may try if I end up tracking the Boss a lot. Though that would not solve the trans or oil heat issues still. But creative routing of the system may help with that.

Has anyone seen any sort of heat sink that can be attached to the trans and hangs down into the scoop?
 
cloud9 said:
jeepinocala said:
cloud9 said:
I saw that on a 5.0 that was in my dealers showroom. I figured they designed them that way to direct either the water away from an area or to assist the airflow out of the hood. I would find out the design intent before trimming it away. The engineers don't just do things haphazardly. There has to be a reason. I will be on track this weekend with a Ford engineer that has a 2013 LS and will ask him if he knows.

I dont think it to HELP air flow at all. I would guess they dont want the rain running on the motor.
Is that opinion based on the wind tunnel testing?

No it's based on the small ass slot the gets the air out after making a 90 degree turn ::)
 
Cloud9,
You've got the track experience that I don't so I appreciate your detailed observations. While I'd like to figure out how to get it down to 220, I could live with 240 as long as the oil temps stayed at 235 or lower, especially since it won't get on track very often. Looks like I need to get the cooler and hood ordered. I believe I'll go with a larger oil cooler than the 302s kit has as well. I will be retaining the AC so that is a restriction I have to acknowledge as well.

The Track Attack LS did run 220 on the track at 6500 feet, mid 80's. Since hp was down a little due to altitude, that may explain why it didn't run hotter. The AC condenser was removed. I couldn't detect any other mods that would explain how they kept it that low.

CaliMR
The 302s grill, higher heat transfer radiator and hood louvers will make the existing fan more efficient moving air through the engine compartment by reducing restrictions to the air flow and the air to carry more heat energy. That works at every speed. The engine oil cooler will also help reduce heat in the motor, but that heat transfer has to be exhausted by the same airflow. The biggest limitations are the restricted grill opening area and the tortured air path to exit the engine compartment. Difficult to get major reduction in those limitations. A bigger lower grill area would be a big help and isolating the oil cooler air path from that of the radiator would also help. The only way I see to significantly increase exhaust of the airflow is up through the hood. An additional vent duct just behind the radiator in the hood similar to the GT500's have would be a likely candidate.

I guess the biggest reason I've pretty much decided not to go for any major power increases is I'm not sure how to handle the increased thermal load with the cooling design limitations. I'll be lurking as I try to absorb the experience of those who are working through the cooling issues. Keep the data coming.

Thanks,
Mike
 
BossDuke said:
I guess the biggest reason I've pretty much decided not to go for any major power increases is I'm not sure how to handle the increased thermal load with the cooling design limitations.
That's been partly holding me back as well. However, I'm not sure that opening up the exhaust via headers and an offroad x would generate more heat since you're allowing the exhaust to flow better, even though it adds hp. ??? Advancing spark timing would obviously generate more heat and from what I've seen there's not much left on the table in that area anyway......which might be why the Boss runs on the hotter side to begin with ;)
 
If you do headers, you can wrap them to keep heat in. That might help a little. You can also wrap the motor in gold foil ;D

I suspect that the emissions stuff is part of why they run hot, modern cars are designed to run hotter to cut emissions and also it is why they have throttle hang and a few of the other annoyances. I suspect you would need an aftermarket tune and change the thermostat to get the car to even aim for a lower temp.
 
ive been saying that for years. and people just dont get it. send them headers to polydyn, then wrap them once they get there coating. then add a blanket. i bet you cut down heat then.

aint nothing going to change coolant temps much if the t-stat is commanding it to stay in the area of 203-215 ect.


steve
 

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