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Discussion Starter #1
Okay i hear alot of people on here that are very conserned with heat soak. A few member have gone to great lenghts to try and minimze heat soak. I do understand that a CAI is better that a SRI for HP but i cant see all that much differance in getting 3*-5* cooler air from a plastic tube vs metal. When the air is moving threw the intake it is cooler than standing air and once at speed the air is moving under the hood so how much hot air is really being sucked up by a SRI? These are things that were going threw my mind so lets see what everyone else thinks.

Also another idea i had, would it be a good idea to have a intercooler style filter hooked up to a CAI? moving air from the front of the car into a intake pipe? would that be something worth looking into.
 

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i wouldnt look into it...sounds like an expensive project with zero actual gain...not to be rude

as far as intake go ive had cai and sri...cant tell much of a difference but im running the cai as it "should" be better! maybe its a lil less boggy i guess!

most will tell you that the stock box, and a good panel filter is the way to go, but i spent the money so ill leave it the way it is!
 

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Contrary to belief the air isn't actually cooler once its moving. Air may feel cooler to the touch when moving but that is because as it goes by your hand it actually removes heat from it making your hand feel cold. Especially if your hand is wet. If you do any data logging you will see that when you press the throttle down at a stop the air intake temps don't get cooler. Its only when you start moving then they get cooler as fresh air from outside circulates in.

Honestly one of the best ways to deal with underhood heat is to remove the weatherstripping from the rear of the hood. Lets lots of heat out.
 

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I went to some trouble to reduce heat-soak, with my two extra fan setup. And I think it was worth the trouble. The main benefit.....the car doesn't have to be moving to get the benefits of the extra airflow. The under-hood temps were reduced about 25F around town, more so on really hot days.

The different methods to reduce the temps.....removal of the hood seal, raising the hood slightly, and the various air-scoop systems.....all have their negatives. They don't work very well at slow speeds, and they all result in more water splashing around under the hood......if you worry about hydro-lock, that is a major concern.

If you run a CAI.....heat-soak is less of a concern, but a hydro-lock is more likely. As far as performance is concerned, you probably won't notice much difference on the street no matter what type of intake you use.

How much heat-soak actually effects you...debatable, and probably not measurable, except on a dyno, or the track.
 

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What bluefront says about the fans is true IMHO. Heatsoak discussion so far has been confined to the intake systems. But no one so far has mentioned the cause of heatsoak. I.E. the engine and the fact that we have the main cat inside the engine compartment (duratec anyway). If you force the hot air out of the engine compartment continuously , then your not going to cause your intake or anything else not mechanically attached to the engine to get hot. End of heat soak issue. The trick is to do it as efficiently as possible. jetrinka prefers cutting the weather strip, which is a good idea, but brings along some problems with it you may or may not want to live with. Bluefronts fan idea is good as well, except that it uses power and that is something you pay for in fuel costs, plus the long term survival of the fans is still an unknown. Here is something you may not know although it has been mentioned by others. I measured the under hood temps after the car was fully warmed. At idle (stop light) the temps quickly (< 10 seconds) exceeded my meters ability to measure (160F. It was just a house type gauge but it has a really long probe wire). As soon as started to move, the under hood temps fell to ambient within 30 seconds. So the air flow through the engine compartment is not as bad as initially thought. Personally, I am going with Bluefronts fan idea. I will be using Comair muffin XL fans (very efficient). I will have 3, and the total average 'cost' should be less than 1 amp. (1.6 amps max draw). jetrinka idea is zero cost, until he blows a hose and drenches his car with hot radiator fluid, and tallies the subsequent cost for that (might be high, might be low. I'm just sayin! :) ) The reason I am going to try the fans is that a cooler engine will last longer, maybe make more power (more than what it uses), and I got the fans for free!
And an intercooler will do you no good. Intercooling works by heat transfer. If your incoming air is at ambient then there is way to further cool it.
 

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Discussion Starter #8
maybe i explained the intercooler idea worng. i was thinking of putting some type of air filter in the place of an intercooler, similar to what S0C0nFused did but with more space for the air to hit. and yes i relive that this would be a huge water log problem in riny season, but i am getting a new daily driver so i'm thinking why not.
 

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GreyRice WOoT!
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its a good idea, but that ammount of air being sucked in by your throttle body isnt going to pull in more due to a larger filter, yes it will be cooler air, but theres a chance of bug guys as well and it may break the filter if u hit an animal lol
 

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i have seen a civic with that filter I posted up the link to and it comes with a shield.

but lol it looks funny with the wana be intercooler haaha
 

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I had no idea they made such a thing (PumkinSvt <> link).
norcalfocus01 >> This 'intercooler filter' thing presents more problems than it solves IMHO. I would not use it personally. 8-P
 

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Discussion Starter #13
thats close to what im thinking im going to draw it out in the next few days and post a pic, like i said it would be for summer driving and track type use
 

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thats close to what im thinking im going to draw it out in the next few days and post a pic, like i said it would be for summer driving and track type use
I've done many experiments with air temps, going all the way back to my 71 240z. a few years back, I installed an inside/outside thermometer device with the wire and small pod, one under the hood near the tb if my 2.3 duratec, and one where the air is ingested behind the grill. There was a consistant 40-50 degree difference while driving, and up to 70 at idle. someone can check, but my memory says 1% power change for each 7 degrees, but that's a 70+ year old memory. Remember, at the lite, that plus 70 is what goes into the engine.....
 

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I have the brackets done and ready to mount the fans. What I need is a temp range for the controller. Using a 3 speed model, what would be the desired low temp, middle temp and high temp (refers to fans spinning slow, mid and high speed).
I was thinking (probably wrongly) that 105f would be a good low speed start point, but maybe that to low. So next sensor is 122f. Would that be better? What do you all think?
Thanks

ACK! Never mind. Forest from the trees moment.
 

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Discussion Starter #16
id think the low 100 would be good you wana keep on top of the heat dont let it build up to high before the fans come on and then them not catch up
 

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SOCOnFused... it depends of the amount of airflow you'll be getting, and the exact points under the hood where you want lowered temperatures. When I built my two-fan setup, I wanted mainly, to lower the temps at the location of the Steeda air-filter. I was having no real problems, but it's quite obviously a benefit to have lower intake air temperatures.

I run my fans at full speeds all the time.....except when it's raining (turn off the lower fan). I'll probably be able to turn off both fans in the winter. I was wanting to keep the air temperatures at the point of the Steeda filter, around 100F max around town. The fans made that possible.

Without the fans, I was seeing temps around 135F driving slowly. I don't get any water splashing under the hood....ever. That's another benefit of fans, rather than simply "venting" the hood.
 

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norcalfocus01 >> Heat won't build up. Bet a Coke on it! :)
viney266 >> Good thought. My primary objections to that were 2 reasons. 1: Cost. 2: Persistent Drag.
bluefront >> +300CFM on high. 'Eyeballing' it, I think we have ~6cu.ft. (which equals total air change out of 50 times per minute, or 1.2 times per sec ). Which also addresses norcalfocus01 question. Note: This is rate on HIGH switch. The goal is to provide total airflow over/around the engine. Basic flow test I conducted showed it worked.
Pics coming soon. Controller stuff should arrive next week.
Now I need you all to think about something and please give it some thought. The downside to fans is this. If you have an engine fire. I have a incorporated a thermal cutout in the design, but where to mount? Front, Back? And just how hot is a engine fire? 500f? I am happy to say I have never had one, so input appreciated.
Thanks
 

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Leave it stock?
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if you got a reverse style scoop there wouldn't be any drag really. I like my roush scoop though, drag doesnt surpass cool factor increase lol.
 
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