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Black is better for dissipating heat apparently

Just to add, NO it is not just normal black paint haha

On my old R34 GTT I had my dumps and front pipe ceremic coated in black and proved the engine bay temperatures dropped by 15-"ish" degrees.

I had the cooling pro turn flow for my old R33 with basic mods: turbo back, 12psi, pods (if these even do anything), and flash tuned by toshi. Before the tune: car was laggy (maybe by 500rpms) but when the boost built up the car definitely performed better. After the tune: no lag, little bit more power but way better response and in general it does help your car stay healthy.

I'm planning to save up for a PWR intercooler for my GTR at the moment which is thicker than standard.

I had an r33 GTS-t which had no mods other than cat-back exhaust and pod.

I put in a big Hybrid FMIC, but unfortunately being a know-nothing chequebook mechanic at the time, it had an entirely unsatisfactory (in retrospect) piping setup whereby it dropped down from the guard in the usual way, went across the front, then had the return pipe snaking back over the radiator to hook up with the cross over manifold.

Don't make the same mistake I did.

Passengers thought it was better but it was just because it became laggier and the power delivery less linear. Boost would come on a lot more suddenly and crack the rear tires loose in corners.

It did stop the heat soak at traffic lights on hot days though.

If you are going FMIC, IMO the best way is to do the job properly and get a front-facing plenum, and set it up GTR style.

Yes, I know, the inlet runner length, I'll have my flamesuit on before the puter posts this up.

Just to add, NO it is not just normal black paint haha

On my old R34 GTT I had my dumps and front pipe ceremic coated in black and proved the engine bay temperatures dropped by 15-"ish" degrees.

I'm planning to save up for a PWR intercooler for my GTR at the moment which is thicker than standard.

yeah but i was talking about a thin coat of black paint on the intercooler not ceramic coated exhausts.

I'm looking at getting one too. I have a 3" turbo back exhaust running 9-10psi, K&N panel filter, dyno tuned to 168rwkw but had problems with my little intercooler heating up and giving us bad runs. I even felt it the other day and it was hot to touch... I wasn't even pushing it.

What gains could I expect... I hear maybe 5-10rwkw according to my tuner, but more so I look forward to reliable power. I don't plan to do a re-tune in the immediate future.

Edited by senilykSkylines

You don't need to get it retuned........wait until you have other mods installed that will affect the tune as well.

You may want to get it tuned???

The thing is, I won't be doing any more power related mods in the near future since the next step is going to cost big $$$; highflow turbo + supporting mods + aftermarket ECU (which is proving diffcult since I want to keep the auto gearbox).

So I guess my question should be: would the bigger FMIC change things sufficiently that a re-tune would get noticeable better results?

Since a basic SAFC 2 tune is only like $100ish, I probably get it re-tuned anyway in the end... :whistling:

Black is better for dissipating heat apparently

I got the black FMIC kit, got black instead of the usual polished metal colour mainly for stealth than anything else.

Edited by Mayuri Krab

The thing is, I won't be doing any more power related mods in the near future since the next step is going to cost big $$$; highflow turbo + supporting mods + aftermarket ECU (which is proving diffcult since I want to keep the auto gearbox).

So I guess my question should be: would the bigger FMIC change things sufficiently that a re-tune would get noticeable better results?

Since a basic SAFC 2 tune is only like $100ish, I probably get it re-tuned anyway in the end... :whistling:

I got the black FMIC kit, got black instead of the usual polished metal colour mainly for stealth than anything else.

yeah i got a black one thinking it was anodized but turns out ws powdercoat which i was advised was not good so I stripped it (that was fun) pretty sure it will make next to zero difference but boredom can do strange things to a man.

oh to the guy running 168kw , i was doing 185kw with stock cooler and no problems so dont expect a cooler to solve it, Id say you might have other issues

Convincing thread.....

....I'm going to remove my 100mm FMIC and just plumb the turbos straight to the intake.

----

Look it's as simple as this. When you move large amounts of air, it heats. What??!?! Yes. Ever felt the air coming from a vacuum? Or compressor piping? Turbo charge follows the same princible. Now as you compress more and more air, it gets hotter. Sure, physically hot turbos are also a factor, but lets put that aside for now.

Now, cold air has a higher density. So more oxygen atoms can fit in the same cubic foot of air. Since the limitation of power is (usually) how much air we can fit in the engine, having a cooler charge temperature will increase power once you tune the fuel map to reflect the change in oxygen density. In a sense, it's like upping the boost by a minute amount.

Also, having a cooler intake charge will mean you can somewhat advance the timing, and again, make even more safe power.

If your intercooler isn't up for the job. The heated charge air will be hotter going in, hotter during combustion, and hotter coming out. This physically heats the turbo, and the charge air is now hotter again. That hot air goes back in, becomes even hotter, etc. I proper sized intercooler will stabilise this. You don't buy an intercooler to make big power, but to make safe big power.

It's that simple.

In regards to black intercoolers it's simple thermal dynamics:

If your heat sink will work in the air flow of a fan, the contribution of radiation will be extremely small, compared to the effect of conduction. So, it's best to leave the aluminum bare, as any layer of black paint, with its lower thermal conductivity, will hamper the conduction of heat from aluminum to air more than it may help by increasing radiation.

In other words, don't paint an intercooler if you want the best results. It's a well known fact aluminium oxidizes and corrodes over time, and paint can increase longevity. So why don't the smart, highly paid engineers paint them?

In other words, don't paint an intercooler if you want the best results. It's a well known fact aluminium oxidizes and corrodes over time, and paint can increase longevity. So why don't the smart, highly paid engineers paint them?

Painting it black helps its heat sink characteristics. The r32 GTR's had black painted intercooler cores (at least up to ~1992). I don't think it was until the 34 that they started making them raw alloy. As to the why - why do people do anything? why do idiots remove the nice, lightweight, forged alloys from their cars and replace them with big stupid chrome rims that are heavier and redice handling? Because of aesthetics. Big alloy coolers look cool hanging out the front of a bumper, and manufacturers know this.

THe vast majority of *factory* coolers I have seen are painted black.

Convincing thread.....

....I'm going to remove my 100mm FMIC and just plumb the turbos straight to the intake.

----

That's why the VL turbo was so amazingly powerful ph34r.gif

yeah i got a black one thinking it was anodized but turns out ws powdercoat which i was advised was not good so I stripped it (that was fun) pretty sure it will make next to zero difference but boredom can do strange things to a man.

oh to the guy running 168kw , i was doing 185kw with stock cooler and no problems so dont expect a cooler to solve it, Id say you might have other issues

I have an auto so apparently if it was a manual it would be doing 190ish... All I know is when the cooler is cold it pulls hard right through (and with the knock sensor turned off) but when it is hot it literally stops accelerating at 4000rpm and then suddenly carries on (knock sensor turned on). Tuner thought it was the hot intercooler causing detonation and the knock sensor was kicking in. He tried multiple variations of afr but it came down to the intercooler we thought. Sometimes he would get 130rwkw on the dyno and the other time got 168rwkw depending on the temp of the intercooler and the knock sensor kicking in.

Better not be something else : l

Painting it black helps its heat sink characteristics. The r32 GTR's had black painted intercooler cores (at least up to ~1992). I don't think it was until the 34 that they started making them raw alloy. As to the why - why do people do anything? why do idiots remove the nice, lightweight, forged alloys from their cars and replace them with big stupid chrome rims that are heavier and redice handling? Because of aesthetics. Big alloy coolers look cool hanging out the front of a bumper, and manufacturers know this.

THe vast majority of *factory* coolers I have seen are painted black.

What I posted wasn't off the top of my head. It's fact. Actually, a line or two I pulled from another document relating to thermal dynamics. Painting aluminium flat black will increase it's ability to themally radiate. Yes, you're right there.

But.

In coating aluminium in paint (even a thin layer) you reduce it's ability to thermally conduct. Aluminium heatskinks (including intercoolers, they are part of this family) are designed for thermal conduction, not thermal radiation. The only time a heatsink uses thermal radiation is if there is no airflow. Nobody cares how many kW you're gonna get idling in heavy traffic. Thermal conduction begins when the car moves... And I'll guess most of the time you're on boost will be with the car moving.

Having a black intercooler achieves a much more standard, factory look. It does NOT increase cooling efficiency trhough conduction. Back then the majority of cars had painted black copper/steel radiators. Now we use unpainted aluminium. We didn't see the radiator before, we hardly see them now, so why the change? Copper is even better at thermal conduction than aluminium too, but price and weight, it's not worth the extra 20% conduction you get from it.

Another example is oldschool hot water radiators people would have outside to generate heat. They'd paint them black to absorb the radiant heat, which creates more heat. It also helps to block thermal conduction, again, increasing the heat further.

Have a read on thermal dynamics, it's got all the info right there.

I have an auto so apparently if it was a manual it would be doing 190ish... All I know is when the cooler is cold it pulls hard right through (and with the knock sensor turned off) but when it is hot it literally stops accelerating at 4000rpm and then suddenly carries on (knock sensor turned on). Tuner thought it was the hot inter-cooler causing detonation and the knock sensor was kicking in. He tried multiple variations of afr but it came down to the inter-cooler we thought. Sometimes he would get 130rwkw on the dyno and the other time got 168rwkw depending on the temp of the intercooler and the knock sensor kicking in.

Better not be something else : l

You still got the stock R33 SMIC or a upgraded R34 SMIC?

If it is still the R33 (tiny) SMIC, it would be heat soaking pretty bad with the upped boost.

My car is auto as well & before I got my black FMIC installed, I had a R34 SMIC in there with the usual bolt on mods (exhaust, POD, boost TEE) + SAFC 2 & the car made ~180rwkw on a average temperature day in Perth (that was about 1.5 years ago though).

Edited by Mayuri Krab

What I posted wasn't off the top of my head. It's fact. Actually, a line or two I pulled from another document relating to thermal dynamics. Painting aluminium flat black will increase it's ability to themally radiate. Yes, you're right there.

But.

In coating aluminium in paint (even a thin layer) you reduce it's ability to thermally conduct. Aluminium heatskinks (including intercoolers, they are part of this family) are designed for thermal conduction, not thermal radiation. The only time a heatsink uses thermal radiation is if there is no airflow. Nobody cares how many kW you're gonna get idling in heavy traffic. Thermal conduction begins when the car moves... And I'll guess most of the time you're on boost will be with the car moving.

Having a black intercooler achieves a much more standard, factory look. It does NOT increase cooling efficiency trhough conduction. Back then the majority of cars had painted black copper/steel radiators. Now we use unpainted aluminium. We didn't see the radiator before, we hardly see them now, so why the change? Copper is even better at thermal conduction than aluminium too, but price and weight, it's not worth the extra 20% conduction you get from it.

Another example is oldschool hot water radiators people would have outside to generate heat. They'd paint them black to absorb the radiant heat, which creates more heat. It also helps to block thermal conduction, again, increasing the heat further.

Have a read on thermal dynamics, it's got all the info right there.

Volumetric efficiency, Thermal efficiency and Mechanical efficiency are all good reads especially in relation to engines, IMO. :thumbsup:

236 was exhaust pod and boost tee. stock 33 cooler

266 was 6 months later but only change was Hybrid FMIC

was while ago so cant remember exact but think run after run was 236,218,210. after cooler 266,264,264

feeling was noticable on the road.

unfortunately scale is slightly different

post-24655-0-51236200-1301057890_thumb.jpg

post-24655-0-02250100-1301057910_thumb.jpg

You still got the stock R33 SMIC or a upgraded R34 SMIC?

If it is still the R33 (tiny) SMIC, it would be heat soaking pretty bad with the upped boost.

My car is auto as well & before I got my black FMIC installed, I had a R34 SMIC in there with the usual bolt on mods (exhaust, POD, boost TEE) + SAFC 2 & the car made ~180rwkw on a average temperature day in Perth (that was about 1.5 years ago though).

Nah just the R33 SMIC. What do you do now power wise with your FMIC?

I have a feeling my Z32 chips knock sensor is rather sensitive :) When we turned it off it just lit up the wheels in second at 50km and 70km (in the wet) where as with it turned on it wouldn't (unless turning slightly), it would have that flat spot.

How does the heat transfer coefficient of naturally occurring aluminium oxide compare to a very thin layer of specialised paint? Normal aluminium oxide needs only be incredibly thin to adequately prevent further corrosion, so despite the far more conductive paints available they probably cannot make up for the thickness of the coat of paint.

The layer of oxidised aluminium is thin and relatively fragile, which is why anodising is used to create a strong hardy layer to prevent further corrosion pretty much permanently. Depending on how this is done, ie what thickness is achieved, it can be thick enough that a paint is more efficient for convection heat dissipation.

All in all, black is stealth laughing-smiley-014.gif

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