STi2EvoX

I am on the fence on this one and need someone with some dyno proven results to step up. The issue is this: most all tests have shown that IC upgrades on the X make between 10-20 HP gains with no loss in spool (which I still don't understand how that's possible with a larger core that would take longer to pressurize), BUT... they have all been on a stock tune. If an IC is put on a stock tune, it can change the boost, A/F ratios, timing curve, load cells that the car is hitting, etc and the gains could be more circumstantial than anything. My concern is this: (and we are talking about the stock turbo, of course) that A: it's unnecessary at these power levels and B: just like a drop in filter or an intake, it makes gains on the stock tune by leaning out the A/F ratios and once a tune is done, the benefits are mostly negated. I want to see a X that is tuned first, then retuned with an IC upgrade to see if there were in fact any gains. Or, numbers from someone with a tune and IC vs another X with just a tune ON THE SAME DYNO.

I am hoping that it still makes power post tune, despite what a few sources have told me. The issue is that their experience is with the 8/9, and they have not personally seen any IC upgraded X's to know for sure. I believe the X is different and that this part may well make power even post tune, and here's why: The turbo on the X is on the backside of the motor where there is much less airflow than if it were on the front of the engine like the 8/9. Second, the compressor housing is VERY close to the manifold, and these two factors have been proven to increase inlet temps on the IC in many tests. So, IMO the X stands to benefit more from a core that doesn't heat soak as quickly and doesn't have to work as hard to cool the air charge. Someone step up and prove me right, because I am tired of debating this with my friends. Thanks guys.

bryans2k

iTrader: (2)

What you are failing to realize is that a larger FMIC isn't so much about adding power the first dyno. It's about stabilizing that power so that it will be there the on the 10th dyno so in that sense it does add power.

The tests where it adds power by simply bolting it on could be the ecu operating in a different range because the X getting cooler air where it was slightly hotter before. There would be no other reason why it would operate in a different range outside of boost levels by simply bolting on an FMIC.

AFRs, better timing curve, etc wouldn't be possible without that consistently cooler air so in the end it's the FMIC that add's power.

So it adds power by stabilizing it and adds power by cooling better.

Why is it so hard to understand?

Bryan

Billy@EnglishRacing

iTrader: (18)

ETS has made power on there X with an intercooler and a flash

linjy2

iTrader: (4)

my take on this through my butt dyno is my turbo takes alil longer to spool now, maybe 3-500rpm longer. i didnt get that instantaneous power i used to get with a stock fmic.

i upgraded to a AGP 3.5" fmic. still on cobb AP stage 2 tune. evo x's i used to beat are passing me up by a fender to a car now on roll races.

STi2EvoX

First off, you are completely wrong about bolting on a bigger intercooler and not having it throw the tune out of whack. It will change the pressure drop and flow characteristics, which will change the boost and the A/F ratios and throw the car into different load cells than it was running before. This will further affect the A/F ratios and have an impact on the timing curve as well. This is the main reason that front mount upgrades make power on the stock tune, and why in many cases it DOESN'T after a tune, hence the reason for my question to begin with. Second, I am not "failing to realize" anything; everything that you said is common knowledge and had nothing to do with my questions. I know very well that a larger core is harder to heat soak and will give more consistent runs on the dyno, but that has nothing to do with what I asked and besides, on the road it is doubtful that the stock IC would be heat soaking anyway (as long as boost levels are within the turbo's efficiency range).

I will rephrase my question again, and hopefully this time someone can actually answer my questions and do it without an attitude. So again, on the stock tune, bolting up a larger IC will change the pressure drop characteristics, which will change boost, A/F ratios, and most likely the load cells that the car is hitting. The car picks up power from this, no doubt. BUT... once tuning is done, are there still any gains? My fear is that much like an intake that leans out the A/F ratios of the stock tune, once tuning comes into play and the A/F ratios are adjusted, the benefits of the intake disappear and the same A/F ratios and power could've been attained on the stock piece. I would like to see stock IC and tuned numbers vs upgraded IC and tune numbers on the same dyno to provide the evidence that I am looking for. I don't see how my question could be any simpler than this.

STi2EvoX

A real world scenario that shows a lack of spool from a larger core, which makes much more sense to me than these dyno tests that magically show no loss in spool and power gains everywhere. Sigh... I am losing hope in my theory that IC upgrades on the X was more worthwhile than on the 9. My friends might have been right... crap. So, were you losing ground just on spool up, or everywhere in the rev range. I would tend to think that once spool had been attained, even if there were no gains, power levels should at least be the same. Thanks for any info.

Clipse3GT

iTrader: (10)

I think the point of doing a IC upgrade. Is to get the proper size for your application. I think if you plan to do only 100-200hp increase, stay within the 3 to 3.5" IC and stay away from the 4" race intercoolers. Bigger is not always better. Also you have to have a goal for the car, not throw everything in there that you can get your hands on and buy.

Getting a cooler slightly larger than stock should improve cooling and air density of incoming air and should not affect spool times too much. So doing all the supporting modification before IC might be key. I.E. CAI,UICP, LICP, DP, TP, and CBE. All of those mods should support the IC, making everything flow better. As well as a proper tune that does not go rich or lean out throughout the RPM range and adjusting the ignition timing.

triguy

iTrader: (1)

A tune got me 25-30 more whp after installing a Perrin FMIC, AEM Intake, and ETS UICP. The exhaust is totally stock. I ended up at 325 whp and 325 lbs of torque on HB Speed's dyno. Before the tune there was lag. The tune dialed out the lag. I disagree with the last post. The Perrin IC is a hell of a lot larger than the stocker and I'm not suffering any downside in performance on the stock turbo.

STi2EvoX

You are probably losing spool, but because you drove around on the laggy, out of whack tune for so long before geting the car tuned, you probably don't remember what the car felt like on the stock IC. It's impossible to not lose a few hundred rpms in spool from a bigger intercooler bro, it's simple physics; a big baloon takes longer to inflate than a smaller baloon. There is no question of this. Now, you say you picked up 25-30 whp after a tune? Of course you did. The tune still further leaned out your A/F ratios, upped boost, timing, mivec was adjusted, etc. The question is, are you making any more than someone with the same mods but on the stock IC?

My gut instinct says you are not. Hence, the reason why I started this thread to begin with. I want to know if a front mount upgrade makes power on top of a tune on the X, because it did NOT on the 8/9. I've gone through the ringer with this one, because I want to believe that it does make power, but I just don't think it will. See, at first I was skeptical and didn't buy into the idea of the front mount upgrade on a stock turbo because common sense told me that there is no way that the stock turbo is outflowing the stock IC or overheating it. But, I held out hope that maybe the X is different...

I started to get a little curious after seeing all these vendor dyno plots before I realized that they were all on the STOCK tune. Did more research, talked with a few experts, and then reality kicked back in. They do make power on the stock tune, but because they affect AFRs, boost, load cells, etc. But once tuned, in most cases add no power and only increase lag. This is 100% the case with the 8/9, and I'm sure applies to the X as well. Despite my wishful thinking of the X standing to benefit more from a front mount upgrade because of the hotter turbo placement and inlet temps on the stock IC, I suspect that results will be the same as the 8/9 and that the stock IC is best for the stock turbo.

KPerez

Anything that increases the density of the air going into the plenum will increase the power output of a modern FI engine with or w/o a tune. So if one replaces the OEM FMIC with a more efficient FMIC (with simliar pressure drop, 1-2psi), the air density will increase and so will the power output of the engine at a given boost pressure. This is due not only to the higher mass of air entering the engine but also the lower temperature which "allows" the ECU to use more timing resulting in more power output.
In general, The larger the FMIC the better. So for each type of car (X, for example), there is a finite frontal area that is available for the FMIC. The effectiveness of the FMIC is controlled by the degree to which this area is utilized with the thickness of the core to a lesser degree.

Later, Ken

NRG

iTrader: (2)

FMIC were never meant to increase power but to sustain power. In another words the purpose of the FMIC is to maintain a more consistent air temp at higher ambient temp levels. So for a smaller core or a core that is less efficient will not be able to sustain the air temp thus your power is also lost. On the other hand with a bigger core and more efficient cooling, it is able to regulate the temp better so not to lose as much power. So the answer to "if FMIC makes more power" no it doesn't but it can sustain your power level for longer time...

That is my take on this matter...

FLK

^I'd agree with what you said. I have made up my mind not to change out the stock IC, because fast spool and throttle response is more important to me than HP.

The ARC and Coltspeed IC are both 2.5" and only about 2% bigger in dimension than stock, but they flow better from a different fin design. Even though spool would be comparable to stock, it just doesn't justify $1200 for slightly better sustainability of power. Even less justified are the 3"+ cores where you lose spool time and response.

KPerez

Yes, it is true they also provide consistent response under multiple boost events. That said, a larger FMIC relative to the OEM unit will make more power because, as indicated earlier, it will increase the mass of air at a given boost level.

I have been waiting for the groundhog to die here so I can dig out and install my FMIC and have it retuned. With this install and tune, I am predicting another 25 whp.

Later, Ken

NRG

iTrader: (2)

^^well again, it is not actually "making" more power directly but indirectly it is helping to sustain more power...

Bosshog

I got no power whatsoever (maybe 5hp at max) from APS intercooler, FR Manifold, injectors and IC pipe on the stock turbo on a full bolton evo 9. I had to get retuned twice to get these results as well - a quick retune (AFRs, etc) first where the car kept feeling lazy do to the larger core and later from a different mapper (dentist from the UK) who managed to eak out a few horses and got rid of the laziness at around 2.5-3k rpm. I would skip all of the above till upgrading the turbo. the usual stage 3 boltons minus intercooler is where its at for bang for buck... now when you are ready to change turbos, you might also consider the intercooler.

Having said that, one benefit of the larger core is in summer times having a bit more stable power when its hot outside. all in all, it might be a worthwhile investment if you live in a hot climate...