Agreed. I got one hell of a laugh out of this thread though,and learned a few things.

 

i forgot which magazine it was but they did a research on wrapping up turbo manifolds and compressor housings they gained like 10hp, no joke. besides i have a big Ol' koyo radiator. so underhood temperatures do matter and every lil bit counts. if you dont believe me go look at import tuner or super street from like 2 months ago

 

Fab,

Everything you said has been pretty much spot on. I think a lot of people are missing the basic aerodynamics principles to understand it however. Let's discuss based on an actual flow diagram. This is a miata, but its all I have on my computer so bear with me.



This is not air PRESSURE this is VELOCITY, but it will give a general idea to work from. I used this diagram when planning my extractor hood and ducting. Typically higher velocity air (red) means lower pressure. So if you wanted to do something that extracts heat you would want to do it at the "red" point. Air is flowing at a high velocity, which means it is a low pressure area.
The air towards the hood/windshield section is "green/blue" (same as the mouth of the bumper" which means it is a section of low air velocity, does this mean air cannot escape there? No. Does it mean that is an optimal location? Hell no. A ducted I/C and rad setup with extraction is far more efficient then hoping the engine air will flow through your whole engine bay and out the back of the hood. If anything, more air will flow out your tranny tunnel because it is the path of least resistance. Anyway, that is all the time I have for today
To the posters who keep claiming that they are doing this mod for "heat reduction", try something like this with proper ducting if you are REALLY that concerned with your CLTs and IATs.

 

Wrapping a turbo and manifold does a lot more than lower underhood temps though, it's also increasing the thermodynamic efficiency of the turbo by keeping the heat in the system. Turbos work off of exhaust energy in the form of heat, so the more you can keep in the system the better. Wrapping a turbo manifold and turbo is also going to do a lot more overall than jacking the back edge of a hood up will. That 10HP gain was not just from lowering underhood temps, trust me, although I will guarantee that the an unwrapped turbo will add heat to your intake manifold much faster than spacing the hood up will take it away.

If you have such a big Koyo radiator, why are you worried about underhood temps that much, because if it's doing its job then it should work well regardless of what other "mods" you think are necessary? The primary paths of cooling airflow should work just fine.. If you're woried so much about every little bit, there are plenty of other (read: non-ghetto/rice) things to do that will actually net good improvements. Race engineers don't say "wow, we're having a cooling problem, lets add some hood spacers". They'd actually solve the problem.

 

I remember, I did the hood gap "mod" on my hatch when I was Turbo B-series with a ramhorn. The only thing it really did for me, was let my manifold not hit the hood anymore. I didn't notice any improvements in power or heat soak reduction.

 

well i wear flip flops alot cuz its was as hot as the 10th level of hell before this cold front moved in and the floor gets super hot, and my turbo is nothing but a heat magnet and underhood temperatures is pretty big under my hood. well then Mr. engineer solve my under hood heat problem without wrapping my turbo because im switching that and the manifold hopefully soon

 

Mitigating heat in turbo cars is not rocket science, its a combination of channeling and controlling the heat generated by the turbo system. It doesn't take an engineer, it takes common sense and searching, because I'm sure it has been done before on your application. Usually separating your intake from the heat using shielding, shielding the turbo (hell you can use an old license plate), and high CFM fans and shrouding your radiator are a good start. You can't wrap the turbo as it stands, and then re-wrap a new one? We can talk about all the solutions you want, but if you don't want to put in work, then what good is it?

I'm sure you'll be more then able to handle a simple heat problem, since you stated in previous posts you were intending on swapping LS1 and 2JZ into your car.

 

lolllllll when that day comes and miguel does this, i will have a jet pack.

 

that was fuckin hilarious...i couldnt stop laughing for a while

 

not really, i would have i just dont have the money right now like some people (jewish 07civicsi). but i would prob do 2jz over ls1. i love me them inline 6 ^_^. and speaking of shit never getting done.........how the hell is your plan coming along......atleast mine is already started and i have almost everything.....i just need more money(like everyone else)