Hi,

I am fitting a load of parts this week to my 2003 WRX
VF34 turbo
Ported Headers and Up-pipe
Full decat exhaust
Walbro 255 Fuel Pump
Hawkeye 550cc Injectors
3 Port Boost Solinoid
Platinum NGK 7 Plugs

Have a cone air filter if needed.

Now I have a STI TMIC and a new Front Mount.
With the VF34 im guessing around 330bhp
Do i go with a FMIC or TMIC
A few have said the FMIC wont be as responsive as a Top mount.
Any advice please!
Thanks

 

Would stick with the tmic unless like me im going fmic as im sitting at 414bhp

 

As above stick with the sti tmic. Front mount will give a bit more lag and the vf turbos don't like the sudden stalling a fmic would give it, they tend not to last long when driven hard like that. Go front mount when you fit a turbo that requires it.

 

The information re vf turbos and FMIC above is a first on me, I've never heard anyone say that.
What the poster is probably referring to is that the VF turbos don't like being run without a recirc valve (i.e. blanking it off) as they're not as strong other variants and can suffer with the additional pressure that's put on them by blanking off the vent, eventually causing failure of the internals.
However, VF's on a FMIC with a recirc or BOV are fine and the FMIC hasn't caused "stall" on my 20g or SC42 and haven't on any of my mates' cars either - as long as it's setup correctly by a person with the right knowledge you're fine.
Personally, I wouldn't run mine blanked off anyway, regardless of turbo as that's probably causing the stall the poster above is referring to!

With a FMIC you will ultimately make more power, but with the turbo you have there it'll max out before you exceed the limits and capabilities of the STI top mount.
I'd also stick with the standard airbox with the mods you've put there - TMIC allows you to retain it so win win - just stick a decent panel filter in there - Green or K&N.

Turbo spool will be slightly quicker and less progressive (i.e. immediately suck you into the seat rather than gradual boost followed by push you into the seat) on a TMIC due to the shorter pipework. A reverse inlet setup can help cure some but not all of that.

 

Exactly what Mr Noisy just said!
VF34 on a FMIC I wouldnt recommend unless going for a bigger turbo. More benefitial with the TMIC.

 

Agreed, vf34 or 18g are relatively comparable.
I have two mates, both with WRX's and still on TMIC's - one runs an AFP 18g, the other a vf34, and both were relatively evenly matched with each other on a few pulls up dual carriageways on the way to Santa Pod for Japshow.
Up until about 50-60mph pull is similar to mine and then I start pulling away with the extra legs the SC42 gives me.

On an 18g, the FMIC will get you better dyno figures but the car will likely drive better and be more responsive on an STI TMIC.

Whilst an STI TMIC in tip top condition should be good for around 400bhp, many are clogged up with oil and other crap from the breathers which you can eliminate with a decent catch can setup, and hence sometimes make as little as 355-360 even with big turbos.
I had a clogged up tmic, wouldn't exceed 355bhp with a 20g, switched to FMIC and gained 26bhp and similar torque gains too.
It actually makes the car less savage, but with a smaller turbo I suspect you'd lose the benefit of the quicker spool it offers without gaining much in the midrange or top end.

 

Thanks for the info guys! I will stick with the TMIC untill I go 2.1 and more power later on.

 

I had a v34 and a front mount, no lag issues on mine, its a setup issue, Harvey (RIP) did alot on this very subject.

once you get over 300 you start to see gains by going front mount, setup correctly and you wont notice any lag.

 

When you say set-up you mean Mapping? or what parts you put together as in Headers turbo intercooler

 

Mapping is a must mate. If you're planning on fitting the above without you're a nutter lol

Tidgy - I agree re lag - it's just the boost is less savage with a fmic from what I found but I actually preferred that. A 20g on a tmic was a bit like being punched in the head lol

Back to back dyno results showed that with the fmic full boost was achieved about 250rpm later than with the top mount but on the road it was barely noticeable. Was just a nicer more civilised drive tbh

 

I wouldn't even say it was less savage on a fm, I've gone from a 340 horse classic to a 400 horse hawk (fm on classic tm on hawk), the hawk is quicker, but feels slower, yes weights a part but the classic was very much nothing nothing holy ****,,,, hawk pulls lower down then kicks when turbo comes in, but not as agressivley.

 

Lol
what a crock of ****.

 

I too have come across the same dilemma ... I have a 2004 wrx and its in at the moment for a vf35 and pinks.. Plus catch can and 3port boost solenoid... I had a fmic sitting there too and I was advised that for my aim of 330 to 350 bhp a sti tmic would be fine... But I fitted the fmic over the weekend and what a nightmare... I wish I had just gone down the sti tmic route now for the amount of hassle it was fitting the fmic

 

you didnt look into it first?

 

Yes I did, the person who is mapping men this week said a sti top mount would be fine, but it was booked in for today to have the turbo,injectors boost solenoid fitted and the re mapping the end of the week and as I already had the fmic I had to fit it or cancel my booking and wait until I could source a decent sti tmic...

 

I'd imagine a large part of that is done to the 2.5 you're running though mate? At least I think I remember that's what you said you had.
On my 2.0 blob it's gradual and then about 4000 rpm all hell breaks loose lol

 

yeah forged 2.5, sc46. as you say its the extra grunht low down that makes it feel a bit tamer, still lights up all 4 wheels from time to time hahahahaha

 

its not a 4 day job you know?

 

I'm sorry I didn't realise I had booked it in with you... My car went in today and I will have it back friday... It takes as long as it takes.... I see no relevance in this at all to be honest..

 

I think he was only trying to let you know so you don't get fleeced.
He's right though, changing turbo and injectors is a few hours for an experienced mechanic with ramps and tools, and fmic took me about a day total split over a weekend on my drive so again someone experienced should be able to do it in less time.
Just so you're aware, it was intended to be a friendly comment I have no doubt

 

I'm aware of the amount if time it takes to fit the parts, its having a little bit more work while its there also, its also having a sti up pipe fitted, plus the gearbox is being changed due to it being made of chocolate and chewed 2 nd gear again.. Then once its all fitted its being re mapped

 

Ah gotcha gearbox change should be fun lol.
If it chewed second should we hazard a guess that you're a visitor to Santa pod or like a bit of track work? At the level the car's at its unusual to see them perish otherwise.
Have you gone for a stronger hawk 5 speed or just a replacement item?

 

Hi there

If you have already STI TMIC stick with TMIC

With FMIC I would go if you are thinking to run more power,but from personal experience I've run VF34 with FMIC and lag there hasn't been issue

With FMIC you can gain like on bhp and torque

Back to back tests FMIC vs TMIC,think Shaun has have tested both on his car and think Steve@The Gimp run on his STI TMIC and after switching to FMIC he gain too on bhp and torque

But in yours case you will be not making above 360-380bhp,where I would say FMIC will be more effective

TMIC or FMIC debate will be here still and both sides have pro and cons


Jura

 

Had only had the car 6 days and 2nd gear went .. I've not launched it and have it had time to track it as yet... The gearbox it self was a recon box 13 months ago so one month out of warranty.. I'm hoping its just one of those things. I have bought a 5 speed from a 2005 wrx but I'm sure it's a blob eye one like mine..

 

Ah gutted mate that sounds like very bad luck.
As long as it's the same hubs etc you should be fine.
The later hawk ones, whilst stronger require additional components from the later car too I believe.
Our resident google expert will be along shortly to confirm I'm sure

 

Comment was slightly sarcy lol

but yeah your talking a few hours to fit one, not days.

There was a test done for jap performance mag back a few years back, difference was about 20bhp at 300 so 300 become 320. Not to mention the current hot weather and sitting in traffic

 

Is there any sense investing in TMIC in a region, where average temperature in winter exceedes 30C? I was considering buying a full set FMIC for my 2009 STI, and keep having the dillema... TMIC of FMIC... ?

 

30C in winter lol. front mount for def, wouldnt bother with a top mount at all, also prob worth looking at an oil cooler as well, make sure its thermostaticly controled

 

welcome to the middle east...

what do you mean by thermostatic control? For the IC or for the oil cooler? (btw. oil cooler was there even before the koyo rad... oil temp measured at the oil filter base never exceeds 95 degrees... even on the track).

 

haha yeah, got realy cold here past day or so

thermostatic for oil cooler, stops it getting too cold