^yeah the FMIC's get destroyed during rallies which the wrx was made for.

I think water/alc/meth injection would be better than a FMIC. It's a constant factor which does not need movement to work.
It turns on at X amount of boost or when you want and can be tuned around. Air to Air IC's depend on the current temps outside.

I've been thinking of this since the summer is coming and my daily driven TII get's very hot during that time and the TMIC won't stand a chance and a FMIC can't do that great in 110+ weather either.

Now of course a FMIC and Injection would totally rock and local guys can prove that.

As for the original thing with the Amemiya one. I don't think it will really help since the stock TII scoop would not cover that section making it an engine bay heat obsorber. Extending the scoop will be entirely too hard to make look right. THe only pro way I would see would to take the hood and cut it half and splice in an addition from a salvaged hood.

 

The biggest drawback of a topmount is how fast it heatsoaks when you aren't moving. That's it. No one can say a top mount is only good at low to moderate boost levels. The stock one yes but you can't just say that any top mount is only good for such levels. This isn't true. No one with any intelligence can also claim that any top mount will never cool as good as a front mount. Again this is just pure uneducated bullshit. The only thing that matters when it comes to cooling an intercooler is airflow. If it gets the required airflow, it doesn't matter where it is. Period. The stock top mount while not the marvel of modern technology actually does quite well when the car is moving. That is when we use the power isn't it? Yes it can heat soak quickly when you aren't moving or you are at stoplights but hopefully you don't buy into the whole street race crap anyways and don't care. The stock mount 3rd gen intercoolers are easily just as bad yet tons of people use aftermarket stock mounts. The ducting on those isn't even as friendly to airflow as the T-II hoodscoop is and the radiator fan is blowing directly onto the bottom of it which heats it up. At least there is ducting so the radiator fan doesn't blow air across the fins.

There is admittedly a lower pressure zone on top of the hood whereas there is a high pressure zone in the front of the car. This is irrelevant to cooling ability though as cooling through a cooler is only determined by airflow and not by what pressure it is at. When the car is moving, there is airflow. In the same manner, when the car is not moving, there is no airflow. This applies to any intercooler location unless you installed a fan on it. There are plenty of Evo's and WRX's out there making lots of power with top mounts. There are plenty of 3rd gens out there making lots of power with stock mounts.

A larger duct on the hood and a larger intercooler would work just fine. This assumes you can fit it all up there. Look at the old Porsche 911 turbo's. They had the intercoolers on top of the engine underneath the rear "hood" of the car where they received their air through louvers at the back of the car. Plenty of those cars make some good power. The current 911 intercoolers are located in the rear quarter panels and get air through ducts and again these ducts aren't getting blasted from a direct frontal assault such as a front mount.

I'm not here to say a front mount isn't the best way to go. It really depends on your situation and intended use. I can say it isn't always the best way to go. This also applies to air/air intercooling vs air/water intercooling. They each have their advantages based on what you are looking for. A front mount will affect your cars cooling ability to some extent where a top mount won't. A top mount will heat soak faster when the car isn't moving than a front mount will. Keep in mind that a front mount will still heat soak. Give realistic answers based on facts and not personal opinions. Intercooler sprayers just serve to help undo heat soak. They can be used with any setup and will probably improve any setup. A good top mount doesn't need it any more than a good front mount does. I'm not even going to get into intercooler sizing for your intended application. Once again bigger isn't always better. We'll also not discuss proper ducting which I have never seen anyone do with a front mount. I'll give you a hint though, if the area of the opening to the intercooler is as large or larger than the area of the fins, or if you can see the end tanks, your opening is too large and you are losing cooling ability. You'd benefit from a smaller duct. Chew on that one for a while.

 

the reason that the temp rapidly rise when the engine is off could mean the air flowing theu the intercooler isnt stuck in the cage getting heated... i mean, thermal transfer works both ways... ?

 

WTF?

 

never thought of that...thats gotta be the reason...rallys are the best

 

use your head and rethink

 

If the engine is off, there is no air flowing through the intercooler. The greater heat rise means there is no air movement through the engine bay whatsoever. This heat has nowhere to go but to heat everything up around it. With the fan on, even with the car sitting still, there is still some airflow through the engine bay. It's hot air but the point is that some heat is still getting out of the engine bay and not soaking into everything. Everything still gets hot, it just doesn't get as hot. Obviously on a car that is off, this will only happen for so long before it starts to cool down but that could be quite a while.

 

take the time to properly explain your theories

 

I agree, first of all air wouldn't be moving "trhu" the intercooler at all if it's off. 2nd, of all, yeah I don't even get your argument enough to be against it. You use a tad bit of chatspeack as well as small too to-the point sentences, it may only seam reasonably to you because you know what you're talking about. also, what is with the last question mark after a statement, not question. It's like the whole "I'm Ron Burgondy?" thing. you may want to spend the extra 2 minutes to type out the point you are trying to get across. what you had ot say sounds intresting, 'd love to hear what you have to say, you just need to talk to everyone here like they're engine knowelegable 13 year olds. They'll get tech talk but as Americans, we like ot relate to simple low I.Q. sentences. However construct them well like that of an 18 y/o.

 

That is not an aftermarket IC. It's clearly one and a half S5 IC's welded together.

Of course it does. Mazda didn't put it there for decoration.

I've done it. I used foil-lined adhesive foam insulation on the IC's backplate. It slowed heat soak a bit but nothing dramatic. A lot of the heat soak is from hot air moving up through the core. Insulation can't stop that.

Go back and read my first post.

Look at all the factory turbo'd performance cars made in the last 15 years and you'll find FMIC's are far more common that top-mounts. Usually they sit in front of one of the front wheels. TMIC's are more common on turbo-diesel cars and 4WD's.

Again, look at all the factory turbo'd performance cars made in the last 15 years (particularly Japanese ones) and you'll see most use a lot more boost than FC's. 10+psi is very common.

And they're not selling WRX's to the same crowd? Yeah right...

All cars competing in the WRC, including the WRX, use FMIC's. I've been to dozens of rallies and I've never seen a FMIC "destroyed" during a rally unless the car hit something.

There are no Evo's out there with top mounts.

 

^Oops you caught me on that one!

 

I thought that was pretty obvious but the caption I saved the picture from years ago said it was an RE amemiya part. So if it wasnt actually modified by RE then I apologize

 

NZ, I usually appreciate your posts, but maybe you should have taken a closer look at your car before posting.

I know of at least two rotary performance specialists that have done this mod. Amemiya is one of them, as shown in this thread. And that is an aftermarket modded ic, even if it is pieces from two S5 ics.

Pull the ic, study the mount points on the UIM, the rat's nest rail, and the related plumbing and clearances. I think there's plenty of opportunity to expand on the OEM set up. With the right hood redesign (a subtle hood mod is essential) and proper extension of the four mount points for the ic and related intake plumbing modifications, I believe that the capacity and flow of a more efficient modern ic design could easily double and perhaps as much as triple the flow of the puny old school OEM ic. The limiting factor would be aesthetics. Viper and others have made it clear that you can make the TII hood look ridiculous with too big a scoop -- I totally agree with that.

My two goals with this mod (a fantasy at this point) would be to try to triple the OEM ic efficiency and achieve a redesigned hood that would retain the aesthetics of the OEM hood scoop. The hood would need to be redesigned, but I am not that sure the the scoop itself would have to changed too dramatically -- just enought that any rotorhead would know something cool was up with the car.

 

You're incorrectly assuming that I haven't looked closely at this before.

Maybe it's semantics, but a workshop hacking up a pair of stock IC's is not really what I'd call an "aftermarket" IC. That term implies anyone could go buy one. I highly doubt RE-A ever marketed a product that looked quite that homemade.

FWIW, I'm planning on (eventually) making a FMIC very similar to that one, using the two S4 cores I have sitting in the garage.

Done that numerous times. The issue isn't plumbing, it's that fact that the IC cannot be moved or extended to the right because it'll hit the UIM. The only way to do it would be to raise the IC up, which would in turn require raising the hood. That'll be a good look... Not to mention that putting the IC hard on top of the UIM will restrict airflow though it and increase heat soak.

IMO if you're going to put the necessary effort into making it work properly, and don't like front-mounts, you might as well do a V-mount and avoid the terrible heat soak that'll be experienced by anything sitting directly on top of the engine and directly under a perfect escape path for hot, rising air.