Here's a chop of my T2 with the hood scoop enlarged to allow an ic about twice as big as normal. I've been thinking about this as a mod. I'm not really hot for the front mount -- top much plumbing = lag and I don't like ripping out all that other stuff to make room. Yes, there are drawbacks to the top mount, but also some virtues, but what is needed is more ic.

I'd like to hear all the arguments pro/con. Let 'em rip. Thanks.

 

even w/ a larger tmic...... your still only getting hot air into the intercooler..... so its function is still way under par! even w/ a widened scoop, there still wouldnt be enough airflow to compensate for the heat coming from the motor...... so all that work and money would be wasted....... and the "lag" from a front mount is almost not noticable...... so save time and money, and just get a fmic

 

well a few issues regarding top mounts were covered towards the end of the V-mount vs. Front mount thread from a few days ago...

But a top mount, even a bigger one that might fit under that wider scoop, would still become a frying pan at not much above stock levels of boost simply because of the amount of heat rising from the motor, and radiating through the parts its against...

It will become LESS of a frying pan when its going 50mph but at 50mph a front mount (or vmount) would be far cooler than a top mount - yes even a larger one.

If it were just that easy everyone would be writing threads about their 400whp beast with a top mount, but instead its threads asking why it doesn't work....

 

Why not use a bigger top mount, and tilt it forward a little bit. Then run some kind of ducting underneath it into a reverse scoop that exits near the windshield? Trying to shove alot RIGHT underneath the hood, but a little bit of heat wrap underneat the ducting to the rear and around the sides of the IC could do the trick?

 

as it is, the stock, skinny tmic sits butt up against the hood, so "tilting" it would make you have to cut a huge hole in your hood, and put some giant scoop on it to cover it........ and again, still not nearly as effective as a front mount, not to mention how hideous that would look

 

also not to mention you'd have to make the car center drive and jack the seat up so your head was out the sunroof inorder to see past your monstrosity - hehe

 

hahahahahahaa......... i got a full visual on that........ lmao.....

 

You should've had a closer look at your car before posting. Have you noticed that the TMIC is offset to the right? Have you wondered why? Go look at where it sits in relation to the UIM. Extending it to the left is not an option.

 

Well, I've always had a slight wonder in my head if front mount intercoolers were the real way to go, and apparenlty, yes they are.

now I just gotta learn more about them...

 

RE Amemiya TMIC


There's also an aftermarket t2 hood with a scoop to accomodate this. I prefer FMIC 100% though.

 

Does any air actually come in the hood scoop at all? What about putting some kind of thermal insulation on the bottom of the TMIC and using a fan on it to push air out of or suck air in through the scoop. Has anyone done anything like this before, or is it not worth trying?

edit: I mean, it'll never be as good as a FMIC as far as cooling. It seems like there has to be a way to improve on it though without chopping around on your hood and whatnot.

 

It just so happens I installed a thermometer in my TMIC, near the outlet.

Results:

Standing still, engine idling, the temp slowly climbs.
Parked after a drive, the temp rapidly rises.
This means the engine fan helps some even when standing still.

After being parked & the temp had gone up to >100, I drove down the street.
At 20MPH the temp started to drop.
At 30MPH the temp fell to ambient (50) in less than 30 seconds.

Summary: The top mount ain't that bad with my mild mods.

 

Why do the Impreza's run a top mounts? Seems like a bad idea that the RX7 proved not to work 19 years ago...I know theirs works a bit better but have you looked at the size of the scoop...MONSTEROUS...idk...Subaru apparantly wasn't thinking straight when they did that...

-Matt

 

and...wouldnt that just extend it more off center? wouldnt they want to extend it the other way?

 

There is an aluminum (or should be) plate/duct that is on the back of the IC to help prevent heat soak from the motor........it COULD be improved however, and in alot of cases, is not present.

Quite true....on my 87 TII I had the boost turned up to flutter between 10-11psi.....the I/C at that point would remain slightly above ambient temp when driving hard (in motion, but revving the bag off it) it would seem to me that a good rule of thumb would be:

Factory TMIC
Factory turbo
even with the boost cranked up as far as it will go....they work together.

any more than that and your TMIC becomes a nice spot to fry eggs on race day

 

Alot of OE's use topmounts due to their short piping and therefore reduced spool times which is what an OEM is after when building a STREET car. Most OE turbo setups DO NOT exceed the levels of boost capable in a typical factory TII, so why would they bother pipe a front mount?

ask the guys who made the EVO....looks(don't flame me, I know the benefits to it, but Im talking from an OEM perspective)

They are selling the EVO to the tuner crowd....why wouldn't they stuff a front mount up there to make all the little civic boys blow in their drawers

 

very true...

 

I think stock boost on an STi is 14.5 PSI.

 

I belive its actually 20psi for the current generation

 

The simple fact is the TMIC is NEVER going to cool as well as a FMIC. Period. Nope. Never. Sorry, draw another number.

You can make it bigger, you can make the scoop bigger, you can put a swamp cooler on it, you can get the intake for a 747 on it....well that might help.

The point is just do a fmic. Blah, its going over heat. Whatever. If you keep the stock fan /shourd with an underpan it won't be a problem. I have a Koyo, greddy fmic, underpan, with some foam stuffed in the important places and I run consistent 190F on water and oil is 190 - 200.

My intake temps with a FMIC average 20-30F above ambient. And when I get on it the temps DROP! Unlike the tmic which the temps climb. (I had an intake temp gauge on it...I know)

Your missing the point about what an intercooler is. You keep saying oh I want to keep the LAG low. That is not what an intercooler is for. An intercooler is to reduce INTAKE temps. Not as an anti lag device.

Also, think about this. You think hotter intake temps will give you a better engine resposne? Nah, intake temps 20-30F above ambient will give you a better response.

James

 

You could run water/methanol injection with the TMIC.

 

I don't know for sure, but thats also why I left room for myself and said most.......but if it is thats pretty wild

Either way, the STI's scoop is much larger and "grabbier" plus they have I/C spray

 

for the cost of H20 injection you may as well do front mount and pocket the extra couple hundred bucks

"That is not what an intercooler is for. An intercooler is to reduce INTAKE temps. Not as an anti lag device."

good point......and the front mount will make the air more dense than a top mount because of its better cooling which will actually help to reduce lag afterall.

 

Ever tried to run an endurance rally with a huge FMIC 2 inches of the ground?

 

Don't forget the 3rd gens are all front/side mount.

If I had the spare cash, I'd go for the hat trick (FMIC, big turbo, stand alone)

In my real world, it's time for a downpipe.