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Im using a map sensor, will it still mess with it Stao?

Edit: and whats wrong with stock airbox?

No it won't, and stock airbox doesn't flow too well.

I pulled mine off and ran a straight pipe with no filter and made an extra 13kW on the dyno.

  • Like 2

-_- back to stock airbox it is

Nothing wrong with the stock airbox, just retarded comments from people who should know better.

Not everyone cares what happens on a dyno with the bonnet open. Some actually drive on the road.

Something interesting I found out today - Put a pod on my car for all the choo choo sounds (not really) but it makes more boost easier in all gears... 1.10 pound in second easily and full boost in third easily.

I had the stock airbox on but I put the pod on with the factory snorkel for cold air feed.

A clean air filter element would likely do that. What are you trying to prove?

Hot air pods are ghey, I have never seen a decent race car running one. It's all about the cold air induction, and I am yet to see one better than the stock airbox on a Skyline.

Nothing wrong with the stock airbox, just retarded comments from people who should know better.

Not everyone cares what happens on a dyno with the bonnet open. Some actually drive on the road.

IATs matter the most post intercooler and not pre.. you could have chilled air being compressed and fed through non efficient intercooler and you'll make less power, prone to more knock than a setup that's compressing super hot air and flowing through a very efficient intercooler.. your car will make more power, will have a lower chance of knocking.

So yeah, pod or airbox does not really matter.. However for cars running a AFM, AFM voltages may change going from an airbox to a pod setup.

Naah, both do mather... If the pre intercooler iat's are lower, the post will be much lower to. So a decent pod, not mounted in a box or shield or whatsoever will imho have higher post intercooler iat's then a stock airbox, on the other side throttle respons could be a bit better caused by less restriction from a decent pod

Also, turbos are a volumetric device. If the inlet density is higher (ie, from cooler air) then the outlet density is also higher. What that means is that 20 psi of boost starting from 20°C outside air temperature, is not the same as 20 psi of boost starting at 60°C underbonnet temperature. There is a fair bit more air in the cooler case than in the hotter case. And you can't just wind the boost up to compensate, because that of course just makes the output hotter, which is detonation causing, etc etc blah blah blah.

Also, turbos are a volumetric device. If the inlet density is higher (ie, from cooler air) then the outlet density is also higher. What that means is that 20 psi of boost starting from 20°C outside air temperature, is not the same as 20 psi of boost starting at 60°C underbonnet temperature. There is a fair bit more air in the cooler case than in the hotter case. And you can't just wind the boost up to compensate, because that of course just makes the output hotter, which is detonation causing, etc etc blah blah blah.

understand, however let's say this, for both (hotter air intake vs. cooler air intake) the:

  • post FMIC IATs are the same, let's make up an arbitrary number 40 degrees Celsius
  • boost source is tapped for the actuator pre throttle post intercooler, let's say post intercooler it's measured at 1.5bar
  • altitude is the same, so 100kPA (probably useless variable to have in this hypothetical)

I doubt there will be a massive difference in power produced, yes maybe a tiny bit difference because now the turbo needs to spin just that little harder to make up for the lack of pressure (due to air density, pre intercooler) so the EGTs might me a little higher or a lot (depending on how much harder the turbo needs to work).

If you were looking at logs, EGTs, turbo turbine RPM yes there might be a "huge" difference, but the end result wouldn't be much different from a pod filter without shielding to a pod filter with shielding.

Not sure if I am even making sense to the masses anymore.

I get your message. I just think that a every single one of your little justifications is lost power that you could have had for free with some cold air fed to the turbo. Most of us are pushing something up against its limit when working these engines. Whether it's the turbo itself, or ex manifold pressure, or inlet temps, or maxxing the injectors.....regardless of which of those, you could squeeze more power out of not having something else working against you as well as that limit.

  • Like 2

it is also about how much air could be shifted. Vs stock turbo to a GT40 at at a bar of boost, compensate half the timing to the GT40 it still makes more power. As for the same reason of why people don't install factory exhausts on a high powered cars. If the stock air box is only made for 250HP, it will obviously restrict and affect drive ability on a 500HP setup. A well made pod enclosure or a custom cold induction system will definitely help getting the best of both worlds.

The roller dyno works fine in setting up the correct ecu parameters. Because the data output do depend on the rolling object, when comes to preciseness for developments and research its not that accurate. As the firmness of the tire, the size of wheels, position of where the wheels are parked and the tension of strap can all affect its power output.

When shaping turbo wheels for very specific applications. the mm in alterations will slightly alter output and we must to be able to compare those changes. Thas is what a hub dyno is good at, without variances the rolling object, the output is extremely consistent and accurate.

There are specific HP determination equation for different regions, assume the same equation is used, with test vehicles perfectly set, the HP reading between dynos should be very similar.

There are many other variants that could alter the performance of a engine, which I have specifically picked and tested those areas using RB engines, data has been recorded and could be found on index page 1.

I have always wondered in regards to the airbox debate. I don't quite understand why your engine bay temps should be so high when the car is moving. Even with a pod, I can't see air temps being an issue when you are travelling at 80 km/hr. Sure when you are stationary they will rise, but temps will quickly be restored as soon as there is some airflow.

Example

If the engine bays air entry is a 1m x 1m and the engine bay volume is 2x2x1m then you have a surface area of 1 m squared and a total volume of 4m cubed

Approximation suggests

@40 km/hr you have 11 m/s of air volume = 3 air changes per sec

@80 km/hr = 6 air changes per sec

@120 km/hr = 9 air changes per sec

Even at 70% efficiency, that is still a lot of air moving through the engine bay.

I can't logically see how a pod could cause the issues that are being suggested even though a pod could benefit flow at higher demand conditions.

Not saying I am right, but my basic maths questions the opinions.

Most of the air in the engine bay comes through the radiator. That adds heat to it. The engine actually consumes quite a large amount of air, even relative to the air flow through the bay. So even though the air intake (pod say) is in the front corner of the bay, it will suck a lot of air from everywhere, including past the exhaust manifold and turbo.

With respect to the moving vs stationary point.......you often want max power when you've been stationary at the lights or similar.

Compared to most other things we do, a proper cold air intake is so easy to do that I don't understand why it's even an argument. In my R32 I put a 100mm duct into the dirty side of the airbox from the front cavity where the SMIC was. Intercooler pipes still go through the original holes.....no-one notices that it's modded.

Edited by GTSBoy

New manifold, it's currently in the post :)

Will be bleeding exhaust pressure/gas at the manifold instead of the turbo housing to control boost. Should be able to keep the exhaust pressure down and heat down which equates to more power.

HAVOC Fabrication modified manifold.

post-22311-0-16006800-1454388281_thumb.jpg

Old setup turned blue after constant track days, clearly shows EGTs were more than not friendly (even on E85).

post-22311-0-25506900-1454388444_thumb.jpg

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