77 replies to this topic

[Soop]

If I could remember how to give cred, I'd give it.

[buzzda]

The OP asked what mods can he do to improve his car. Surely the benefits of a FMIC are an improvement over stock. Is it necessary, maybe not, but is it an improvement, yes. That’s not in debate so surely thats the answer to the original question.

Yep, agreed 100%.

At what point (power-wise) does it become necessary?, or is that a "how longs a peice of string" question?.

[B4TT]

I am a fan of the Hyperflow TMIC I put on mine - def better than a stocker, still gets some heatsoak in the city though.

Only reason I won't go FMIC is because its a bit of buggerising around on the B4 - if I was to spend the money doing that than why wouldn't I spend the money converting to single turbo and so on.

to throw one more spanner into the works - what do you guys think of WAIC - not the stock RS style ones but the newer ones offered by PWC?

[Soop]

WAIC is the most efficient at cooling the intake charge.
But you've gotta consider the weight, and cost of filling them. I've seen some fairly elaborate WAIC setups with boot mounted radiators + thermo fans just for the intercooler.

[acres]

Yep, agreed 100%.

At what point (power-wise) does it become necessary?, or is that a "how longs a peice of string" question?.

I wouldn't say it's necessary at 'x' amount of power but rather when air flow exceeds the capability of the stock TMIC, ie. when a larger aftermarket turbo is fitted. Or when running maximum boost levels off a stock turbo as this will push the compressor into a very inefficient area of flow -> charge temps will go up significantly.

[Alex]

which uneducated smegma-ladden nobgobbler neg repped me?

I challenge the spineless jellyfish to contribute something to this thread.

clearly they've not only failed abortion, but also to read what I have written, which was essentially what aek had written.

Sorry if I insulted you, wasn't my intention.

No dramas mate. Just lets keep the discussion about the subject matter!

Like I said that article was just an example, but if you could be bothered/have time to read it they go into detail about how to improve your top-mount to make it as efficient as a front mount. I don't care where it came from, someone's obviously done it and proven it works.... maybe some people would rather go down that path than an easily spotted front mount?. As Nik said, some people don't like the look of a front mount so getting the best top mount is what they're after.

I expected a better example than that. I mean, American cars have different tunes, different motors, different fuel, different climate. It would have been if it were a factual analysis. Merely, it was a bunch of opinions. So I immediately disregarded it. Not just because of my own real world factual experiences, but it was a shit article!

Maybe some people want to keep the stock I/C. Wouldn't it be more beneficial to let them know what the stock I/C will handle rather than just tell them that it's crap?

I never said they were crap. I was merely answering the question the OP was asking, about increasing power outputs, that FMIC was superior to TMIC, pound for pound, dollar for dollar.If you want to retain a TMIC, then power increases are not as incrementally significant as a FMIC. Winding up boost, say 5psi, having a TMIC may only yield 5kw on the dyno for example, where same circumstance, same turbo, but with a FMIC, would yield a 20kw increase. What I'm saying is, that for modification purposes, a FMIC is better than a TMIC.

There's also the question of why do Subaru continue to use a top mount set-up?

Economics. Simple.

As Soop pointed out, using a more efficient turbo will decrease air temp post turbo, therefore lessening the cooling load of the I/C. Some may be happy with that result, yes agreed, they could have more with a front mount but if it's not needed (car is making power they want without heatsoak issues) what's the use?

Using a more efficient turbo? In terms of what? BB vs Brush bearing? One fifth of bugger all difference. Probably only measurable on the dyno. Smaller turbo? Decrease power, which defeats the purpose of increasing power. Larger turbo? Will increase heat, and lag, therefore, not more efficient. Although turbo selection would be a thing to consider for power increase, its not really a valid consideration for a TMIC vs FMIC debate.

TBH when I re-build mine I more than likely will go front mount myself. But found the H/flow TMIC was sufficient for what it had.

But if you had a FMIC, it would have made more power, for the same effort exerted by the motor.

My intentions were to have a discussion providing both pro's and con's of each, so people could make an informed decision about what's better for their needs.

That was my intention also, before I was personally attacked.

Most certainly!

[Tom]

Wow this thread took off, it was interesting reading, thanks everyone!

AEKONE: + rep for that post, pretty much hit the nail on the head with that one in my opinion, yep that's pretty much what I was asking. If I was to go and try and get more power out of my car, I was looking to see if I would need to upgrade the top mount to FMIC. I guess not straight up, but if I'm pushing more power then yes I guess it would have to be an upgrade I'd have to look at!

[Soop]

Using a more efficient turbo? In terms of what? BB vs Brush bearing? One fifth of bugger all difference. Probably only measurable on the dyno. Smaller turbo? Decrease power, which defeats the purpose of increasing power. Larger turbo? Will increase heat, and lag, therefore, not more efficient. Although turbo selection would be a thing to consider for power increase, its not really a valid consideration for a TMIC vs FMIC debate.

Bigger turbo doesn't necisarlily mean more heat, but as you say. Totally depends on the application and the turbo choice. If you're trying for 250kw, then a VF11 isn't going to do it, and will super heat everything insight. (I use the VF11 as an example only)
So aside from the TMIC vs FMIC arguement, the OP needs to decide what he wants from the car, and find out what he's turbo is capable of and decide from there.

Tom - If you think you're going to go FMIC at any time in the future, don't spend $900 on a POS TMIC.

[acres]

Using a more efficient turbo? In terms of what? BB vs Brush bearing? One fifth of bugger all difference. Probably only measurable on the dyno. Smaller turbo? Decrease power, which defeats the purpose of increasing power. Larger turbo? Will increase heat, and lag, therefore, not more efficient. Although turbo selection would be a thing to consider for power increase, its not really a valid consideration for a TMIC vs FMIC debate.

More efficient in terms of compressor efficiency not lag, boost threshold or bearing type. A more efficient (this usually but not always means larger) compressor will flow the same air, at the same or less boost, with a lower increase in charge temps. This is a valid consideration to the original question of stock turbo + FMIC vs upgrade turbo + TMIC. The differences in efficiency can be anywhere between 60% and 75% which can make a substantial difference. Not saying this is more important just that it is something to consider and again as was mentioned earlier it depends on the original turbo, upgrade turbo, demands of the engine, etc.

Threads been great so far, plenty of info.
Ta

[buzzda]

Sent an email to Subaru yest asking why they still use the top mount, here's the reply:

Dear Mr Brown,

Thankyou for your email to feedback at Subaru Australia.

The main reason that the designers and manufactures fit the intercooler
to the top is for efficiency. For the fact that it is fitted to a
'Boxer' designed engine, allows for space and it is mounted directly to
the intake which is in the same vicinity. Being mounted closer allows
for better efficiency.
To mount it at the front means its further away from the engine and it
can create less air flow for the air conditioning evaporator and
radiator. It would also be subject to more damage from foreign bodies
(rocks) in motion on the road.

Hopefully this satisfies your curiosity.

Kind Regards,

Chris McFarlane
Customer Relations Representative

[Richo]

So its to keep the aircon heat exchanger and radiator efficient.

[aekOne]

apparently

[buzzda]

Don't forget the rox!!!!!

air cond>power

[Soop]

lol, I wonder how they see it as being more efficient?

The other points make sense, but pfft!

[skillionaire]

Hi,

Can't believe you emailed Screwbaru. More floored that they replied! Nice work Buzz.

Cheers,
Nik

[buzzda]

lol, I wonder how they see it as being more efficient?

The other points make sense, but pfft!

Efficient = responsive?

Hi,

Can't believe you emailed Screwbaru. More floored that they replied! Nice work Buzz.

Cheers,
Nik

haha cheers, yeah was bit surprised myself.

[Alex]

Don't forget the rox!!!!!

air cond>power

LOL

nice going!

it'd be the rocks i'd say, with Subaru's rally heritage. The rest is higgilty piggilty.

[skillionaire]

Hi,

This is my favourite thread on SC.

Cheers,
Nik

[Soop]

LOL

nice going!

it'd be the rocks i'd say, with Subaru's rally heritage. The rest is higgilty piggilty.

Yup, which I said about 10 posts ago .

I'd love to see what information Subaru have to suggest its more efficient.

[B4Cruiser]

wow. interesting thread.

I've gone FM for my B4 not for power but due to its shocking heatsoak and pinging issues. Sure, there are B4's out there with little or no pinging at all during summer (lucky b@stards!) and the TMIC is more than sufficient for their needs.

As for extra lag, imo and experience i can't really notice the difference from the stock TM but the FM does give you more flexibility to play with timing etc with retuning so that lil extra urge is noticable for me. As with everything, each to their own and every Tom, dick and harry will have their opinion; this thread is proof of that.