Fmic On Stock Application

[SKYPER]

Limpus,

At the moment I'm trying to achieve a higher power figure than

a mates car with stock sidemount. I do know with front mount

that I could achieve the same power figure but that would be

too easy.

Edited January 7, 2008 by SKYPER

[limpus]

^^^ I can see your intention in taking on your mate...abit of friendly rivalry is always good and for whatever reasons they are yours and we can't fault you...

However...the discussion here is about a fmic on a stockish application...and the facts are that a fmic is beneficial for the fact that it cools the charge and it flows better than the stock smic...while a smic might support pretty good power...wouldn't it be better to support that kind of power with a larger element of safety which an fmic gives? and even on a stockish application...a larger element of safety would still be beneficial...and with the added advantage of slightly more power...

[SKYPER]

Thanks for the kind words.

This is what I have learnt from my reasearch (please don't quote me on this) -

From my reasearch into the subject, cooling also comes from flow through the core, core length, pressure drop.

FLOW THROUGH INTERCOOLER CORE

The stock side mount on R32, R33 GTS has problems with removing the air behind intercooler

due to small louver vent in the wheel arch. The result is hot air heat soaks the back

of the intercooler core. On the R34 GT-T Nissan solved this problem with a sidevent

(passenger side of front bumper), just behind the intercooler core.

Here's a photo of a R34 GT-T and the side vent -

http://digiads.com.au/carsales/used-cars/c...74.054981_1.jpg

Also thickness of core plays a roll, as air touches the cooling fins on the outside of

the intercooler core for a longer period of time.

With a front mount intercooler you have the added benefit of the engine fan which helps to move air through

the core. But the downside is heat soak from the intercooler core affects the radiator and watertemps.

Also the aircon core on the R32, R33. R34 GTS and R32, R33, R34 GTR doesn't help as it blocks some of

the air reaching the radiator. On the R31 GTS-R you'll notice Nissan moved the aircon core to the underside

of car. I don't understand why they didn't do this with the later model GTS and GTR???

CORE LENGTH

With core length the air has more time too cool down, which is where a front mount is worth it

over the small length side mount for 100% percent throttle racetrack applications. Some say

the cooling affect happens within the first few centimeters of the core length.

CORE PRESSURE DROP

Pressure drop affects how long the air stays inside the intercooler to be cooled.

The ideal pressure drop is from what I remember, around 0.5-1.5 psi at a certain

boost level. The stock sidemount intercooler provides this perfect pressure drop

up until a certain boost pressure is reached. If pressure drop rises, it becomes a

restriction and should be upgraded to a bigger size core.

That's why 13.5psi (R32, R33 GTS), 14psi (R34GT-T) at 0.5-1.5 psi pressure drop

with the stock sidemount intercooler and stock turbo sounds reasonable considering

the size of core.

I noticed the S15 side mount is good for 1bar (14.7psi) and has a similar size

core to R34GT-T, but I think has a smaller T28 turbo.

From what I remember there are size and CFM flow charts you can look

at to decide on core size. Basically match turbo CFM at a certain boost

level to intercooler core CFM at certain boost level.

I guess the mismatch in CFM flow is why alot of cars that are fitted with

big front mounts with stock turbo's are actually slower than the same car

with a stock sidemount that is matched properly. Fitting a bigger turbo

increases the CFM, so it makes perfect sense why the car performs better

on the drag strip.

Also does anybody know where to buy a side vent, like the R34GT-T side vent???

Edited January 8, 2008 by SKYPER

[R338OY]

Great bit of research there SKYPER,

I agree with you that a properly matched turbo, boost pressure and intercooler, regardless of size, are more important than just whacking on a FMIC.

I have a stock turbo and R34 GTT sidemount on my R33. I chucked the 33 SMIC and when i installed the 34 one the difference was noticable. The factory 33 SMIC is really only intended for factory boost, or a little more.

I have a mate that threw a FMIC on his stock turbo 34 GTT and was disappointed. He preferred the responsive SMIC.

I have been advised repeatedly from Skyline owners that a stockish setup (esp. 1 BAR or less of boost) really won't benefit from a FMIC. There are more power gains available with exhaust and ECU mods.

I'm happy with the SMIC setup, it's zippy and flows quite well for my 12psi. I don't think the safety knock factor really comes into play on hot days with such stock power. For peace of mind just don't thrash it on high boost when it's 35 degrees outside

I'll only bother with a FMIC with a turbo upgrade, the ceramic turbos can't take big boost anyway, negating the need for one when the SMIC does the job.

[SKYPER]

Thanks.

Also Greddy, etc made some bigger upgraded sidemounts

if you want one for R32, R33, R34.

It's just finding a sidevent to vent the hot air behind stock

or upgraded sidemount intercooler, to get the full cooling

benefit of the stock intercooler or intercooler upgrade.

It has to match contour of side of front bumper and size

is important, as it needs to fit behind the intercooler.

The only vents I have found are EVO side vents, 400R replica

front bumper with the massive sidevents (I prefer the stronger

plastic looking stock front bumper to fibreglass replica's).

Edited January 8, 2008 by SKYPER

[limpus]

Nice write up...and valid points too with regards to sizing which i agree with...theres one more factor though...how about the restriction of the charge flow inside the core...

In the end...and this is my opinion only so feel free to disagree with me as i'm sure lots of people will...a fmic while not necessary is still beneficial...even on a stockish car...also...i find it hard to believe that a car with a reasonable (not oversized) fmic will be slower than the same car with the standard smic...this is from personal experience so take what you will from it...

[FATAZZ]

on my 32gtst i have a 34smic. That venting problem you speak of was over-come by not properly tightning up the inner plastic guard then running over it ripping it off.

on the other side where the A/T cooler is i was abit more professional and cut out a square in that same plastic inner guard. Done & Done!

[TTT]

we've had this thread/argument recently.

My thoughts are that if you are using the stock turbo on yor R31/32/33 gtst, then an R34 GTTSMIC is all that you will ever need.

it will flow and cool more than anything the stock turbo on your R31/32/33 will be able to produce.

This also allows the front of the car to stay open to flow plenty of air to your radiator.

The fact is this.

If you have an R33, an R34 GTT cooler is a direct bolt on.

so you spend $150 to buy one, unbolt stock item, rebolt new item and you are done.

If you upgrade your turbo later and have the need to a FMIC, then unbolt your R34 GTT cooler and sell it for $150.

you lose nothing.

If you have an R32 gtst, you will have to take your stock cooler and your R34 GTT cooler to a place that can do aluminium welding and point at your R34 GTT cooler and say "Make the inlet and outlet on this one the same as that one (pointing at your R32 cooler)"

Pay your $50 and go home and bolt it on.

when you change your turbo and need a fmic, sell your modified R34 SMIC on here for $200 as it is modified to be direct bolt on for the next R32 GTST owner.

you lose nothing.

The fact is that it has been proven to flow and cool well at around 200-220rwkw or so.

an RB20 with stock turbo will get no-where near this.

an RB25 with stock turbo will come close but not reach it.

FACT - Colder/denser air = bigger bang, which = more power.

fair enough.

going by that taking your stockish car to a dyno run, doing a run, then installing fmic and doing another run "may" show a higher power figure of a few kw.

But what it won't show you is the loss of throttle response.

if you don't increase the boost, it will feel shit.

Notice I didn't say lag.

if your turbo was getting full boost at 3000rpm before, it will still do it with a FMIC.

I say throttle response.

as in idling along then planting your foot.

[SKYPER]

Thanks for sharing your thoughts on the subject GTST.

I have seen in a magazine (from NZ) a higher flowing front

mounted GTi-R intercooler with CA18 motor. I wonder

if that's another solution for a stock turbo and R34 GT-T

intercooler or will the piping be too long and affect response??

Limpus,

That very long core length part baffles me when looking at the new R35 GTR

which is used on the racetrack -

http://image.blog.livedoor.jp/jdm_kumiko/i.../2/724e0858.jpg

You'll notice in the photo above that the size of those cores

are smallish but enough for engine to produce around 480ps

(roughly 462hp SAE). As GTST has already said, smaller core

seems to be better for response.

But you'll also notice they are front mounted, which seems

to give better flow.

Trying to boost up a R35GTR with a simple exhaust upgrade

seems to result in a 0.1 bar increase over the stock 0.8bar,

as ECU seems to stop the boost from rising above 0.9bar.

That is true about flow inside the core, as bar n plate and

tube n fin cores affect the flow. Bar n plate is supposedly

not as high flowing as tube n fin.

Although in saying that, doesn't the HKS R33GTR dragcar

run a bar n plate intercooler core with a 1500hp motor???

But that dragcar does have proper ducting for the

intercooler, etc, similar to F1 racecars.

Thanks FATAZZ for the alternative idea.

There's also 2 styles of bigger louvers you can buy from ARC

in Japan. I think they are made of aluminium. I guess just

need access to a metal shop or hotrod shop and make your

own louvers.

Edited January 8, 2008 by SKYPER

[eddieeeee-ro]

just get the FMIC, ur gonna upgrade the turbo anyways haha when u get over the power.

[HUAWEI]

With all these opinions I'm still wavering between the FMIC and the R34 SMIC!

I do have in mind a turbo upgrade down the track. I have a feeling mine will give up soon.

[limpus]

Then you have your answer...

[rev210]

With all these opinions I'm still wavering between the FMIC and the R34 SMIC!

I do have in mind a turbo upgrade down the track. I have a feeling mine will give up soon.

Get the R34 SMIC, it's best bang for buck for the stock turbo and when you are ready for the turbo upgrade it.It is easy to sell the R34 smic and basically get what you paid for it.

There isn't any hassle fitting the R34 smic or removing it, not really 'saving' any addtional hassle when upgrading the turbo comes. hell you are going to be upgrading lots of things that will keep the car off the road so it won't be an issue.

Most of all you may change your mind about what turbo you want or what you are doing with the car several times, meaning the best type of intercooler to suit may vary in that time.

I'm of the opinion a $300 el'cheapo intercooler belongs on an el'cheapo bunky car. It's a directionless corner cutting move.

There isn't any indication that the stock intercooler is a real impediment to the standard turbo in actual performance on the track, either drag or circuit (the ceramic turbine isn't sustained lap friendly anyway). based on the spectrum of times people do. You can see people run low 13's even 12's with either with the standard turbo for instance.

so I think the smart way is to do both and enjoy the best possible results from each step, without any extra expense and verry little effort

Edited January 9, 2008 by rev210

[RBwhatever]

Just get the front mount. Your already thinking of another turbo, an intercooler will be one less thing to think about when the time comes.

If your going to stay with your standard turbs then the r34 side mount is your friend.

I had the r34 smic fitted, now i have a fmic on the stock turbo. I didn't feel any detrimental effects everyone seems to about, in fact seat of the pants said it was better, then again seat of the pants could be lying to me, but i'm happy with it.

Mind you the only reason i changed was because i managed to damage the r34 smic in a slip off the road in the wet into a ditch. It put a nice leak in the cooler. Back then r34 smic's were being sold for $250. There was no way i was going to pay $250 when i could get a complete fmic kit for $380.

[HUAWEI]

I bought an R34 SMIC today for $200! Gonna install it tonight.

Edited January 9, 2008 by HUAWEI

[Alex_r33s2gts25t]

Make sure u flush it out, 50:50 metho kero mix and blow dry it dry before u whack it on...

Also its prolly more than a night time job lol it took me in the vicinity of 7 hrs lol prolly cause i made it up as i went along

[FATAZZ]

your standard smic has probly never come off before so it will be quite STUCK.

when your underneath pulling on the cooler,get a friend to hold the IC pipes sterdy in the engine bay.

Yeh dont forget to flush.you'll SEE the black stuff come out.

[HUAWEI]

I realised I wouldn't have enough time to do it last night so I've left it for today. I just got the front bar off.

Thanks for the cleaning tip!

[WAN73D]

hate to spoil ur fun but i didnt have to take the front bar off...and others on this forum haven't had to either while installing r34 gtt intercooler on r33 series 2...

not bragging...just for future referrence for anyone reading this and about to do it

did take around say 4-7 hours ...just fiddling around.

haven't tried a FMIC but i'm +1 for stock look (no defect) and getting most out of stock turbo before having to spend upgraded turbo + massive amounts on other parts for the even bigger power.

[FATAZZ]

LoL 4-7 hours stuff that,take the front bar OFF its 2 screws and a few cable ties

and spend only 15minutes fitting the cooler,not even AL