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i know it makes sense that if u have cold air running into the engine, it won't run as hot....but i didn't think it would b really that noticable...

with my stock box, my temp gauge is at about 5/8th the way up

i got a two piece integra CAI, chopped and put it pointing down (not in the wheel well, wouldn't fit, but have it coming straight forward and curved down to just below where the stock box used to b.....i'm going to make a splash guard yes)

now when idling or cruising below 80, my temp is still at 5/8th, 120 and it drops to just a hair over half, but 160 and it almost gets as low as 3/8th

is it normal to effect it THAT much??

So...
the faster you go, the cooler the engine coolent gets, it sounds to me like your themostat may be slightly bad. Even if its 15+, the coolent will still cool very quickly when driving at 160, thats if the thermo is bad.

But if the car never did this before the CAI, i wouldnt know what to tell you, but im sure someelse here can...

MOSES wrote:So...
the faster you go, the cooler the engine coolent gets, it sounds to me like your themostat may be slightly bad. Even if its 15+, the coolent will still cool very quickly when driving at 160, thats if the thermo is bad.

...

There's a 30 degree disparity between the temp the thermostat opens and the fans are activated.

hold on...a cai only keeps intake air temps a bit lower, not engne operating temp, that should be the exact same as without the cai

Dom wrote:hold on...a cai only keeps intake air temps a bit lower, not engne operating temp, that should be the exact same as without the cai

I believe you're correct on this. CAI was never intended to adjust overall engine running temps. Primarily it's intention is to draw in a cooler heavier air that will give a better overall fuel/air mixture for better combustion. I'm no science wiz, but i believe it has to do with the density of the air. That's why you'll see certain tests give corrected reading based on sea level barometric pressure 29.92" mercury. The cooler and denser the air incomming the better. That's why I keep harping on you numties not to put the cone filter of home made CAI down in behind the rad. All you're going to achieve is having the cooler outside air pass through a hot rad... get warmed up and then pass over the cone filter. Boys and girls, if we pass warm/hot air over to/through the cone filter do we still have a CAI? Class answer ==>>> NOOOOOOO. Solution ==> retain oem air box because it is a CAI designed system or route the CAI tubing to a filter that is not ... NOT resident in the engine compartment. Has anyone really thought why you see so many ebay CAI's come with aluminum/plastic/fiberglass deflector plates?? To isolate the cone filter from any possible heat source.
Not sure how many times it has to be explained or pointed out that the oem system has it's ducting routed to draw air in from a pinched sealed openning between the hood and the rad tubing. Sealing the joint between that tubing and the airbox itself will lend to a better overall system. Bottom line, air must be drawn from a cool source ====>> the engine bay is a hot air source. No brainer in my books.

so basically i'm looking at maybe a bad thermostat? i just had it replaced the day after the cai was installed cuz i overheated on the way home.

If the thermostat is stuck open, thatn I would expect your car to take longer at getting up to temp than it normally would.

ACtually, I had that happen on the 626, the thermostat got stuck open after it overheated and i had to get it replaced. That probably happened to you to

but it WAS replaced after i overheated. how common are defective thermo's?

i heard the "fail-safe" one's I've been told are unreliable and fail-prematurely.

Jack,

Good post. I've often looked at the CAI 's that seem to sit just in the engine bay and was always dubious of them. And I've looked at the intake on mine and it looks like its a good intake system- it rams from outside so thats the coolest you will get. I guess the only thing is the way its routed into the airbox at a maybe too sharp angle and obviously the filter in there. But if you say the OEM is good to keep wouldnt you just repalce the OEM airfilter with a K&N one that slots straight in? Also I did'nt quite get what you meant about sealing up the intake at trhe bonnet??Can you go over that again for us numpties.

so.....
lets get back to this posters' problem, why does his car get cooler the faster he goes, and he wants to know is it beacuse of his CAI,

answer should resemble the following....

YES------NO

and then explain why.

yes sir!..............

erm Moses , theres room enough for eveyone to play...

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Use to be the proud owner of a 323 w/auto-tranny. Overdrive circuit operated off of engine temp. Driving back from hunting camp the car would not go into overdrive due to faulty thermostat (stuck open) and dang near frose my butt off because we had no hot water in the engine ( temp guage registered just above [size=18][/size]COLD.[size=12][/size] I meant 'frozen' and fuel mileage went to 'nuttin'. used almost half tank to drive 76 miles back home. After rigging a piece of card board in front of the radiator everything went back to normal. Also new thermos are made by humans who have been known to mess things up at times. I would suggest re-replacing the thermostat.

I do believe cold air in the combustion chamber will make explosion even hoter than warm air.

Explanation: Combustion is quemichal reaction between oxygen and fuel, so more oxygen, more combustion. More combustion, more heat.

A good example of this is the use of EGR (hot exaust, less oxygen) to lower combustion temperature when power is not needed.

Would this be a valid theory? dont know if I read it someware or if just imagination.

wow...someone dug up an old thread!