Well....I am, going to chime in here for what it's worth. I agree that the hoodliner will not create more heat in the engine compartment. Has anyone really looked at the grille area on an SS? It has more grille area than any three other new cars you look at.
I have been a GM and ASE Master Technician for thirty-plus years and have worked on a few Turbo cars through the years.
Buick is where I worked and they have produced a few rather fast turbo cars in the past. Anyone remember a "Grand National"?
The electric cooling fans in these cars do a fabulous job of cooling the car at idle and the grille area will take care of it at speed!
I don't care what you attach to the underside of the hood!

 

The car is Liquid cooled and air cooled Turbo cars need a lot of air to cool them off they get really heated quickly. You dont think that Intercooler in the bottom front is for looks do ya

 

If noise is more important than performance, go for it. However, if you don't mind sounding like a delivery truck at idle, you'll be better off without the extra 40# under the hood. Or... if you're like me, you could stand to lose 40# yourself, which would mean you could have both

 

An intercooler doesn't cool the engine. It cools the air charge coming _out of_ the turbo.

 

Not having a vast knowledge of Turbos (or anything for that matter ),
my question is; the colder the air gets through the intercooler, would be more likely to produce more power, correct? If that is the case, if there was something else added to the intercooler area to cool the air even more so, then you would really see an increase in power? The reason being, a friend had mentioned some type of device that was out years ago, which cools the air through the intercooler, with nothing needed to do to the engine. He is in the process of getting me this info. Just found it interesting

 

This is correct (to the extent that the computer tuning will "allow" you to add more air to the system*). Some ways of cooling that air charge... electric fans, ice, water spray, etc. However, none of them are really practical for a daily driver, and the benefit is not as much as simply having an intercooler in the first place. Unless you're going to do quarter mile racing (real drag racing... not just test and tune stuff), I wouldn't bother with trying to augment the stock intercooler system. It's got a good air volume, but not so much as to exascerbate the lag, and a good cross section that catches plenty of air.


Whoops... forgot to explain the * above... I am confident that GM engineers included "safeguards" in their maps that limits how much you can tweak the air charge going into the engine. As an example of what they may do-- you've made mods that significantly increase air flow (in this case, by condensing/cooling the air well beyond stock). The fuel injectors are only capable of pumping so much fuel before they peak out (spray volume and cycling speed). But you're driving more air into the system because of your mod than the injectors can keep up with, so you are leaning out the engine (think *ping*). That's a good way to ventilate the top of a piston, and so the computer freaks out at the lean condition and retards your timing to compensate... so there goes your power gain from the mod.

 

Turbo compresses air which causes friction. Intercooler brings air down in temperature before entering cylinder. I believe both methanol and nitrous can be sprayed on the intercooler to reduce air temperature. Obviously this is less effective then setting up a nitrous system, but i doubt you would see any benefit if you did not tune. The whole purpose of temperature in an engine is meeting the optimal burn for your car. All cars are different. If you start changing the temperatures and don't tune then i don't see any added benefit. Lower temperature just allows for more timing and getting a little more out of the engine. This is easily shown just in the canned tunes provided by the programmers. GM allows for all environment tunes so you could drive your car from a Canadian winter to death valley and not worry about it not operating.

On the hood liner issue, there is no doubt in my mind that the hood liner is a result of keeping costs down on the car. This car is $24K versus the Solstice GXP which hits almost $30K with the same engine. There is not a whole lot extra in a solstice that would account for that $6K extra except the fact that the HHR would not sell at all at $30K. Hoodline removal on the assembly line would cut a bunch of money. Dell wanted to remove the Intel Inside logo from their computers because it cost them the equivalent of $5 or so to put it on. That figured out to be about a couple hundred thousand a year saved. I believe Intel now foots the bill. So if GM makes 5,000 HHR SS per year on a specific assembly line i'm sure the removal of the hood liner will save significant dollars for a low production car.

On the heat side, i really doubt the engine is going to suffer from the hood. One of the benefits of having a turbo is that the intercooler creates a somewhat standard for efficiency. The idea is that a NA engine is dependent on surrounding temperature, while the intercooler can lower temps a specific amount always guaranteeing a safer temperature range. Now a car standing still eliminates that advantage and both NA and FI suffer. You should see that problems the LS1/LS2 crowd suffer with heat soak and all of the novel ideas they've come up with trying to cool it.

 

LT1GMC, apologies for hi-jacking your thread, hopefully all related to the hoodliner in question...

XXL thanks for that info, great points being made, it would seem pointless to do a mod and then have the computer not adjust for it.

Razinhell also thanks for the info, about heat soak, I to suffered from that on my 94 25th Anniv T/A. Especially during the summer months, it was brutal. What I did to eliminate it was install a tune that adjusted the fans, (both #1 & #2) on the engine. And believe me it worked. Did not go to cool, but cool enough to do away with heat soak. Also did the same on my C5, GTO, & the SSR, and will probably do the same with the SS, have to see what temps it runs at when it really gets hot this summer. And then make sure whatever tune I get has the provision to adjust the fan temp.

 

I was kind of surprised that the fans do not continue running for a while after you shut off the motor. A lot of cars will do this to reduce heat soak (including our BMW), and I would think the turbo would benefit from this. It is 100 deg here right now, so can't say that it hasn't been hot enough to activate it.

 

Why make the intercooler work harder by trapping more heat under the hood?