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extremely high intake temp need some suggestion.. help appreciated

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Old Jan 24, 2007 | 02:53 PM
  #26  
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Would putting a fan behind an upgraded SMIC and a vented hood help remedy heatsoak in traffic? That way the hot air is being sucked out from the SMIC and vented out of the hood vents. I'm just brainstorming here
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Old Jan 24, 2007 | 03:50 PM
  #27  
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Originally Posted by dabigesii
Would putting a fan behind an upgraded SMIC and a vented hood help remedy heatsoak in traffic? That way the hot air is being sucked out from the SMIC and vented out of the hood vents. I'm just brainstorming here
That has been discussed and done already by a few people. Do a search and I'm sure you'll find some threads on it.
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Old Jan 24, 2007 | 06:52 PM
  #28  
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Originally Posted by Mahjik
Maybe, but your not on boost so it's not really an issue (especially due to the richness that our cars idle at).
It may be an issue to the thread starter, who has not mentioned at what times he is experiencing high intake temps.

Originally Posted by Mahjik
Yes, Adam was exaggerating a little but I know what he was getting at.. Its just not really that big of an issue unless like Rynberg mentioned, someone is tuned to the edge.
Actually, I was not exaggerating. If you are stopped in traffic, and your coolant temps are 200 degrees, everything in the engine bay (including the air) is going to heat soak to that temperature.
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Old Jan 24, 2007 | 07:48 PM
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Originally Posted by Mahjik
Things to keep in mind, you are using ambient air to cool your intake air. If your ambient air is in the 90's (like it is in Malaysia), then you are already starting with high temps. Add in the fact that the stock IC is a little small, you instantly have high intake temps.
90's is in Farenheit, hot days are like 35 degrees celcius... normal days are 30 degrees celcius impossible the ambient air is 90 degrees... my blood will boil ....

coolant temps are around 100 on the hot days... 90 on normal days...

BTW, my car is sucking in radiator air the hot hot ones because the intakes is just right above the radiator fan.....relocating to the place where my overflow tank was doesn't help at all ? should be better than sucking in those more than 90 degrees air above the radiator right ?

at least gives me 10 or 20 degrees difference then i slowly source for a larger intercooler...
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Old Jan 24, 2007 | 08:00 PM
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wow..i'm amazed on how much help i get here...

okay.. let me tell more stories about my intake temp...

let's say i start my engine with intake temp at around 35 to 38...degrees
then i go on the road... the intake temp start raising... it's a very hot day... water temp at around 103... the intake temp raising... keep rising until 50's... once in a traffic or slow moving... the raise is faster.... after some traffic... some long drives combination of idling.. the temp hits 80......

stopped for awhile... and goes back on.. due to the heat soak it hits 90... and stayed constant around 85 to 90.... unless i pop the hood and let it breath and pour water on it.
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Old Jan 24, 2007 | 08:01 PM
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i'm estimating.... the air that i'm sucking in... so called radiator air... should be i guess... 90 degrees due to my water temp is 100....

if i relocate into cold intake.... i guess.... 40's.... at least not above my radiator...
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Old Jan 24, 2007 | 08:25 PM
  #32  
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Originally Posted by adam c
Actually, I was not exaggerating. If you are stopped in traffic, and your coolant temps are 200 degrees, everything in the engine bay (including the air) is going to heat soak to that temperature.
If there's little to no air movement, conductive heat transfer from cooling system and other hot engine parts to the underhood air slows considerably. And by the time the underhood air gets anywhere near that temperature, the radiator fans will come on, keeping temps from reaching that point.
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Old Jan 24, 2007 | 08:32 PM
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Originally Posted by NAN777
stopped for awhile... and goes back on.. due to the heat soak it hits 90... and stayed constant around 85 to 90.... unless i pop the hood and let it breath and pour water on it.
That's about right for the stock IC in hot weather.
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Old Jan 24, 2007 | 09:14 PM
  #34  
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that was fast nan777. we hooked up the datalogit to nan777's car and we managed to bring the knock levels down which was our primary purpose for tuning. i was shocked to see ait at 90c, for a while i thought that was the water temp. the problem mow is as follows - at 84c i've set the pfc to retard 6degrees. when the car is cool and we gunned the car it was very smooth in trasition but after 3 runs when temps went up to 86-93 lots of its performance went down the drain.
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Old Jan 24, 2007 | 10:02 PM
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Originally Posted by Kento
If there's little to no air movement, conductive heat transfer from cooling system and other hot engine parts to the underhood air slows considerably. And by the time the underhood air gets anywhere near that temperature, the radiator fans will come on, keeping temps from reaching that point.
With stock fan engagement, fans won't come on until 220 degrees, at which time they will move out hot air. However, if sitting for a while before fans come on, engine bay air temps can easily go to 200 due to radiant heat from engine & turbos.
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Old Jan 24, 2007 | 10:30 PM
  #36  
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Originally Posted by dabigesii
Would putting a fan behind an upgraded SMIC and a vented hood help remedy heatsoak in traffic? That way the hot air is being sucked out from the SMIC and vented out of the hood vents. I'm just brainstorming here
I can't add anything scientific to this debate but my fathers bronco has a cowl hood on it. When driving with a partially frosted (or fogged) window there's always a streak of clear window right behind the cowl and tapering up to the top of the windshield.

I don't think the solution is to keep doing what you were doing before. You need to get better ducting to your intercooler & log your IAT's after driving around. If your intercooler is heatsoaked wait till the airflow (that you're not getting now) cools it off- then you'll have lower IAT's
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Old Jan 25, 2007 | 05:26 AM
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of all thinkings and brain storming and asking around...

stuffing the intakes at the oil cooler side will draw water.... too much water will kill my motor... so... bin that idea....

i'm getting the IC upgrade.... to a frontmount.

can i have an example of what a good front mount setup looks like ?
i need to focus on the inlet and outlet pipes.... don't wanna cut it and seal it replacing it with another one on top etc.... vertical inlets or horizontal inlets ?
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Old Jan 25, 2007 | 05:36 AM
  #38  
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oh yeah... how big or how small should i get.... i need a rough estimation to ask my supplier to source it out.
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Old Jan 25, 2007 | 09:41 AM
  #39  
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Originally Posted by adam c
With stock fan engagement, fans won't come on until 220 degrees, at which time they will move out hot air. However, if sitting for a while before fans come on, engine bay air temps can easily go to 200 due to radiant heat from engine & turbos.
Radiant heat only transfers to solid surfaces (basically light rays converting to heat). Heating air (which is conductive heat transfer) requires a lot of surface area, continuous airflow, and major differences between the two mediums. It's why a pocket of still air is such a good insulator (a thermos, or why people can survive blizzards in a snow cave).

Even if you were "sitting still for a while", it would require a considerable amount of time (and a lot of surface area with actual temps much, much higher) for the "still" underhood air to reach that temperature. The radiator fans will come on far before that point.
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Old Jan 25, 2007 | 09:50 AM
  #40  
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Originally Posted by NAN777
stuffing the intakes at the oil cooler side will draw water.... too much water will kill my motor... so... bin that idea....
How will it "draw" enough water to "kill your motor"? Are you planning on doing some amphibious driving?
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Old Jan 25, 2007 | 09:58 AM
  #41  
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i don't know that's what the mechanics say... it killed a RX8 by drawing fresh air during rain time... you never want to know how heavy is the rain in my country... just imagine your shower tap... that's what u get when it rains...
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Old Jan 25, 2007 | 10:16 AM
  #42  
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Originally Posted by NAN777
i don't know that's what the mechanics say... it killed a RX8 by drawing fresh air during rain time... you never want to know how heavy is the rain in my country... just imagine your shower tap... that's what u get when it rains...
I wouldn't even worry about. You can play with your intakes all you want, but unless you get that IC changed your intake temps are going to stay the same.

Here are some various core sizes for FMIC's:

Blitz:
length: 58cm (23.2") (not including endtanks)
height: 34cm (13.6")
thickness: 10cm (4")

Greddy 2-row: 276mm x 600mm x 76mm
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Old Jan 25, 2007 | 10:42 AM
  #43  
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With the weather you have, I'd be more worried about coolant temps than air temps. By going to front mount, you decrease the car's cooling capabilities especially in stop-go traffic or low speed situations.

If you get a FMIC, you will need to spend time sealing/ducting it in order for overall cooling to be effective.
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Old Jan 25, 2007 | 01:33 PM
  #44  
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I would try to change the degrees that the radiator funs turn on using the datalogic for the Power FC. That way the fans will turn on sooner and keep your water temps lower. Malasia sounds like a very hot and humid place...and I thought Louisiana was bad lol. As far as the air intake temps I agree with everyone else and say get an upgraded intercooler. My personal opinion would be to go with a nice SMIC or a Vmount (if your funds allow you to go that route) because with the heat in your country you want as much air flowing to your radiator as possible FMIC block most of the air going to your radiator. Also do you have an upraded radiator?
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Old Jan 25, 2007 | 01:50 PM
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Listen to Mahjik, you need an upgraded IC.
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Old Jan 25, 2007 | 03:27 PM
  #46  
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Originally Posted by NAN777
i'm estimating.... the air that i'm sucking in... so called radiator air... should be i guess... 90 degrees due to my water temp is 100....

if i relocate into cold intake.... i guess.... 40's.... at least not above my radiator...

wait ... first of all... DO you have a factory IC duct ???? Maybe your cooling your Intercooler with your hot radiator fan ??? .... It doesn't matter how or where you relocate your intake. ALL turbo car's intake air depends on your Intercooler. The air filter just make sure its clean and working.

having a SMIC the duct is the most important.

2ndly... factory SMIC should go into the trash or ebay as soon as you get the car. The core is tiny as hell, nice way to dissipate hot air temp with such a small core... NOT!!!
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Old Jan 25, 2007 | 03:48 PM
  #47  
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okay... i still have my ductings.... still it's hot as hell
i heard about radiator temp raising due to reduced air going to the radiator. i don't have an uprated radiator... but i'll sort with the intercooler first... water temp later to deal with...

BTW, is the intercooler thicker the better ? ehehehehhe
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Old Jan 25, 2007 | 03:54 PM
  #48  
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Originally Posted by NAN777
BTW, is the intercooler thicker the better ? ehehehehhe
If you have enough air flowing through it, yes.

As far as a SMIC verses a FMIC, they have their trade offs. Generally speaking:

SMIC: Doesn't block air to the radiator. However, it's located under the hood so it can and will heat-soak while the car is idling and not moving.

FMIC: Just the reverse of SMIC.

Also, SMIC are generally more responsive when it comes to the turbos. This generally has to do with the amount and bends of the piping. In the Corky Bell book he talks about the performance loss due to the length and bends of IC piping. For my needs, the SMIC is a better choice since I don't do drag racing where heat-soak would be a problem.
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Old Jan 25, 2007 | 05:53 PM
  #49  
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I'm backing off my prior FMIC suggestion, best for charge temps but not for AC. Also, only the old obsolete apexi fmic (not gt) did not seriously obstruct the front bumper opening.

All considered, I think the ASP medium smic and duct, with a fan, would be the best option. Open intake could be shrowded for cold air pick up. This is the set-up max pictured here:

http://www.maxcooper.com/rx7/how-to/ic_fan/index.html

I'd also make a shroud on back of IC, where fan is not. And relay IC fan to come on when main fans do (adding manual switch for main fans). Otherwise rad fans will cause hot air back flow through SMIC, helping it to heat soak.

Also, get a fluidyne (alum) rad and alum AST, and change all rad caps each year ... pressure is critical in preventing overheating.

For more intake air cooling, water injection systems have been used with success on several FD's.

This path is relatively well beaten.

If I were in Malasia, I'd want a very good AC system.
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Old Jan 26, 2007 | 04:51 AM
  #50  
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nice.... thanks for all the input... really appreciated....
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