al503

I think Lexus did a very good thing in terms of making the upper intake plenum/manifold out of plastic instead of aluminum. Much less heat soak and lighter.

Tony1

I never gave all this any thought, but now that I've read all your posts,
It defiently makes sense that the Joez pipe will increase air temps,
(after the engine gets hot) that is.. By how much exactly? Who knows,
but it's stands to reason it could cause you to lose a bit of power.
Needless to say, If i get a Joez Intake, I'm going to find some good black
thermal tape and wrap the hell out of it

Ramon

I understand EXACTLY what the joez intake accomplishes, where you go wrong is HEAT. The fact that it is only making 4-6HP on a non-heat soaked setup is a concern. How much do you think it will make when the temp increases by well over 100 degrees? At best, you're probably back to stock, at worst, you're loseing power.

4TehNguyen

iTrader: (1)

ill bet the intake tube temp when your actually driving (high intake flow) is going to be a lot lower than idle (very low intake flow), and I wouldnt be suprised that it would be close to ambient during driving. Feeling the intake at idle doesnt really prove anything

i would say replacing just a tube for that much power gain is great, despite still using the stock airbox and stock filter

caymandive

iTrader: (2)

I'm surely not going to be doing any type of racing in 100 degree weather anytime soon and as I pointed out earlier heat soak is not and should not be a concern here. You guys are putting too much thought into this heat issue. Even at the highest temperature the pipe could possibly get on a 100 degree day you are not going to lose power, but on a worse case scenario maybe only gain 1-2hp. A gain is a gain and for the price the JOEZ is a winner in my book.

al503

Taken in the best light of your position, I think the key words here are "at a high enough speed." However, what is high enough? Regardless of the speed/volume of air, you can't cheat the laws of physics and accelerate air so fast that it won't be affected by its container/surroundings.

Also, what testing procedures did they use? Off the top of my head:
1. did they have the car at idle for any amount of time or did they run the engine at higher rpms allowing the tube to cool down before taking the measurements?
2. did they have the hood open or closed? My guess is that they left it open for their measureing tools. I guess if you drive around with your hood open....
3. how many fans, if any, were blowing into the engine compartment?

Agree that construction of the intake is probably more important than materials. However, why not have the best of both worlds by making a rubber/plastic joez type intake?

In addition, I always take a magazines info/advice with a grain of salt where it's livelihood is on the line. It would be hard to imagine SCC saying that aftermarket parts don't do diddly when that's the entire subject matter and reason for existence of the mag and where they get their advertising dollars.

I guess it all comes down to whether smoothing interior of the tube and eliminating the resonator overcomes any heat soak issues, real or imagined. I think there's enough info on this thread so that the forum members will be able to make at least an educated guess.

Ramon

4TehNguyen, you seem to have a misconception of the laws of physics... When you're actually driving, you're using more energy, hence, creating more heat. The only reason it is not as hot when driving is becuase the air is passing through the intake and INTO the motor. That's what is cooling it down. If the heat was simply being dissapated into the atmosphere, like it does with your radiator, then all is well. That is not what is happening, the heated air is going straight into the motor. The problem ends up being two fold. First, hot air itself simply generates less power than cool air, and you also run the risk of losing even more power if you start getting knock retard which is entirely possible as the weather starts to warm up for the summer.

jcreech

you got ripped off...that joez pipe wont do crap. wait for the CAI.

al503

here's another take on the heat soak issue.

http://www.team-integra.net/sections...?ArticleID=410

"Whether you have a cold air intake, short ram intake, or even a stock intake, the temperature of the air that enters your engine effects your performance. Cold air is beneficial to engine performance because it is denser. This causes more oxygen to enter the cylinders, more fuel will be added and more power as a result. This is why you would want to build a heat shield for your intake.
Even cold air intakes can transfer heat from the engine bay to the air being sucked into the engine. Try driving around for 15-20 minutes, then stop and open your hood and feel your intake tubing. You will notice that it is pretty hot, especially if you have replaced your exhaust manifold and no longer have a heatshield. Now imagine how hot your intake tubing gets while you idle and wait your turn to drag, or AutoX. In these situations where every hundredth of a second counts, its worth a little money and elbow grease to protect your intake from engine bay heat.


Theoretically, for every 11-degree drop in air intake temperature, an engine can increase performance 1%. If you think of that in reverse, for every 11-degree increase in air intake temperature, the engine can lose performance by 1%. That means that just by idling before your run down the track, you could be setting yourself up for losing 2-3whp from heat. The difference is enough, where teams like King Motorsports wrapped their iceman intake to prevent engine bay heat from soaking into the intake temperatures."

4TehNguyen

iTrader: (1)

again touching the intake during idle is a poor indication of how hot it really is during driving. Go right on ahead and put some heat wrap on it, there will be very little gain and aesthetics wont be very nice

Lets Drive

iTrader: (3)

I believe there is always a balance that has to be met when modifying a car, so more power usually leads to less engine life in one form or another. I do agree with this point, but offer a link to some actual data concerning filter flow rates and actual filtration. 4TehNguyen, I know you inquired about this as well, so it may be useful.

http://www.bobistheoilguy.com/airfilter/airtest1.htm

I'd say there is only one real way to find out, but based on my experiences, when the pipe heats up, its a given that you will see a hinder on power. It will still flow better than the stock accordion styled tube, but I believe wrapping the JoeZ intake to isolate radiant heat from contacting the metal would be the best option.

Also remember, that part of the equation is not only how aluminum absorbs radiant heat from the engine bay, but also how it releases it (in our case, the concern of heated air entering the motor). I would say there exist little difference of actual power produced, concerning volumetric efficiency or how much air is allowed to freely flow into and through the engine (1), and actual heat (2)contaminating oncoming air over the length of the pipe. As caymandive stated, the amount of time the air spends in the pipe matters, which is relative to its velocity. In an ideal setup, you'd have a perfectly filtered, unhindered amount of cold air flowing into the motor, but with this intake mod (which still uses the stock filter), you give up one for the other, IMO neutralizing the benefits, but still not losing power. I strongly believe other factors, such as elevation and actual ambient temps being drawn into the motor are more of a concern. I haven't gotten a look at the exact mounting of the radiator in the 2IS, but it could also be an issue.

Ramon,
What were the outside temps that day you were driving? Also, if you feel like answering, what city do you live in (so that we can get the elevation)?

As al503 brought up before, I think its easier to see on a turbo engine, where the air is compressed and heated rather quickly after meeting the compressor blade, afterwards providing the intercooler with the duty of cooling the air before it enters the motor. Heat soak definately is easier to see there, but the principle is just the same.

Ramon

You are again missing the point, it does not get that hot while driving becuase the heat has already been trasnferred into the engine and is consistantly being trasnferred into the engine. That is exactly what you want to avoid. That is the whole point of this thread. I don't see why that is so difficult to understand. The heat has to go somewhere, it does not simply go away.

As far as which is better, design versus materials, that all depends. If the Joez was a significant design improvment over OEM, the added heat may have been negated due to its superior design. However, the design is only marginally better, versus the heat which is significantly more.

caymandive

iTrader: (2)

This is good discussion. Threads like this are always interesting.

So in conclusion the JOEZ intake mod isn't affected much if at all by heat, but by adding some type of radiant heat wrap to it and eventually adding a higher flow filter we will have an optimum setup for the most power thus far without actually having a full true aftermarket CAI. The heat wrap may just be an option for warmer days... readers decide. ya?

caymandive

iTrader: (2)

No way heat is significantly more. I'm going to have to disagree with you there. The only time I can think the heat may be more is if the car is sitting idle at a long redlight on a hot summers day and the air is not going into the engine at a good pace allowing it to warm up slightly more than the stock pipe. That small volume of air is almost instantly gone as soon as you stomp on the gas. We also have to remember the stock pipe absorbs heat too.

Ramon

It is in interesting discussion indeed, but how did you come to that conclusion??? There is a gerneral concensous that heat DOES effect performance, the difference being that some people don't think it is enough to outweigh the benifits while others do. There is absolutly no solid evidence yet that it is not effected by heat. I was in denial too when I first started thinking about it, I did not want to think that I just spend money on something that isn't going to help, but it appears that way. My conclusion is the exact opposite.

Shinobi-X, it was about 80 degrees that day.