Heat reduction hoods
- Thread starter LBarr2002
- Start date
Should you wrap the header and cats??
I dont think a Computer fan would last too long under the hood of a vehicle.
I dont think a Computer fan would last too long under the hood of a vehicle.
I read a lot about header wraps trapping mud and moisture against the header and rusting them out quicker. I can't afford to replace that catted pipe...
Yeah, would need something sealed...
I just installed one of PSC's louvered panels on my Yj and noticed a drop on my temp gauge. I have not checked underhood temps yet but I will say that the hood is way cooler to the touch. With the louvers and the TNT fab fenders I have plenty of underhood ventilation.
~Jeff
~Jeff
Years ago I met a guy who stuffed a Chevy Vortec 8.1 into a Jeep TJ. It was impressive. However he had a lot of heat issues.
He ended up using a couple of small 12v fans to help get hot air OUT of the engine compartment. It really helped.
Now one thing I want to ask, is this on a carb'd vehicle or a EFI vehicle? Because on an EFI vehicle, you should be able to "flush" the evaporated fuel out and get clean fuel in just by running the fuel pump for a few moments. However on a carb, you are screwed.
He ended up using a couple of small 12v fans to help get hot air OUT of the engine compartment. It really helped.
Now one thing I want to ask, is this on a carb'd vehicle or a EFI vehicle? Because on an EFI vehicle, you should be able to "flush" the evaporated fuel out and get clean fuel in just by running the fuel pump for a few moments. However on a carb, you are screwed.
It's EFI. Stock '04 TJ 4.0. The system does not have a return to the tank. Once fuel is in the rail, the only place for it to go is out the injectors. With a return system that is true that you could key on a few times and circulate new fuel, but not here.
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So, If you switch the key on and off a couple times before you start it will the fuel pump prime the system and have better results? IE compress the vapors more and pack more liquid fuel in the rails? Sorry we have gotten off topic.
I doubt it. The vapor will compress some but the initial run of the fuel pump when key is on should bring the system up to the regulated pressure, whatever that is for a tj. I doubt additional runs of the pump would increase the pressure, it will just circulate fuel from the regulator back to the tank.
I also read somewhere that the injectors will not open for the vapor, they have to have liquid fuel at the injector to function. Don't know if that's true or not though.
The samurai has a couple slots in the side of the hood right in front of the cowl. I wonder it that was the intent of those? Although it's no where near as sealed up under the hood and it has 1/3 the size motor generating heat...
With the hood louvers, how much of the under hood heat will get sucked in the vent intake just below the windshield? I would assume if you have a valve cover oil leak or anything else that makes unpleasant smells under the hood, that would get vented and pulled into the cab also...
With the hood louvers, how much of the under hood heat will get sucked in the vent intake just below the windshield? I would assume if you have a valve cover oil leak or anything else that makes unpleasant smells under the hood, that would get vented and pulled into the cab also...
Any thoughts on this? Dad rode a little in a jeep with the full poison spyder louvered hood and said the dash vents felt like the heater was on.
you will probably just have to put it to always use cabin air for the inlet, or lock it that way mechanically. Really no need in a jeep to not use full cabin recirculation anyway. Your other option is to not worry about the temps and replace the fuel rail with a flow through system. Then the fuel has a chance to be cooled and to clear a vapor lock.
I think his louvers are pointed so they act as a cowl induction pushing air into the engine compartment. What If you flipped them around, they would just act as a vent... Heat rises....
To actually act as cowl induction and get fresh air pumped in through the vents they would need to stick up a couple of inches to get out of the low pressure zone over the hood. As air comes up over the grill it creates a low pressure zone over the hood which is why water on the hood doesn't just get pushed off as soon as you start moving. Plus he is trying to get heat out once he is parked and everything starts to heat soak due to the lack of air movement. At that point the vents are only allowing hot air to rise anyway. It is amazing the spike in engine bay temperatures once you park a warm vehicle. I have seen diesel engine bays climb upwards of 30°C over where they were with the engine just idling.
You could always setup a vacuum based vent cover if you are really worried about your AC inlet getting to hot. I used one on my old buggy that would actuate a vent based on engine vacuum.
You could always setup a vacuum based vent cover if you are really worried about your AC inlet getting to hot. I used one on my old buggy that would actuate a vent based on engine vacuum.
I like the vacuum opening idea, but you're getting wayyyy to complicated.
It looks like the poison spyder thing has the majority of the louvers open to the back and the few rows at the back edge of the hood open to the front... don't know if there's some science behind that or if they just thought it looked cool. Maybe it creates a vortex!
Anyway, heat will radiate out either way when stopped. When moving, I would think open to the back would be better to keep crap and water from entering.
It looks like the poison spyder thing has the majority of the louvers open to the back and the few rows at the back edge of the hood open to the front... don't know if there's some science behind that or if they just thought it looked cool. Maybe it creates a vortex!
Anyway, heat will radiate out either way when stopped. When moving, I would think open to the back would be better to keep crap and water from entering.
With mine you can see the heat coming out of the louvers on the hood. The hood and fenders stay cool to the touch now to. As for the heat going into the cowl I cannot say because I have a cowl block off plate. I got tired of having to clean the drain out every couple of weeks.
~Jeff
Just noticed he has a actual 2 inch tall scoop that is mounted on that windshield vent.