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Hi guys... I have a fairly stock R33 GTST basicly just has exhaust and boost controller.

I installed a 600x300x76 FMIC over the weekend and notised a fairly big drop in power.

I was running 10psi before FMIC and 10psi after FMIC.

Before FMIC in a strait line in first no mater what if your foot was to the floor and above 4000rpm the back tyres would light up like nothing else. Then if you shifted fast into 2nd the back end would step out and fishy tale hapily. (I have 2x 265s on the rear)

Now I get no wheel spin in 1st and can't get it to loose traction at all when smashing it into 2nd :thumbsup:

Is this just because it lags more with FMIC..? I have my AFM before turbo should I move it closer to the TB?

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Where are you measuring the boost from?

Is it from the intake manifold, - or the turbo to wastegate line? (where it would read the same but not be!)

Also, silly as it seems, some people have left packing or rags in the FMIC inlet/outlet and had this problem! :thumbsup:

You will notice a drop in response and maybe a little power if you fit an after market cooler to a fairly stock car.Because now the air has to travel further through your newly installed piping which probably snakes through the engine bay.But now that you have installed it you can run more boost providing you will get an ECU in the future.

yeah i wouldnt change to fmic till more mods were done or more boost is used, 10psi is fine for stock cooler, ave some coin for a hiflow then u should see the gain, i had stock cooler on mine till about 2000k's after engine build, car still went good on highway with stock smic but around town was alittle less responsive than with fmic. basically i would think u would need afew more mods to see the real gain the fmic will do to your performance...cheers

I am reading boost from my intake manifold.

I can't run any more than 10psi because I hit boost cut at 10.5psi

with smic I could run 12psi before boost cut but i assume thats because 10psi of colder air is probably the same amount of air compared to 12psi of warmer air.

A stock gtst doesn't need a FMIC, it only causes pressure drop. A FMIC is a supporting mod for when you get a bigger turbo.

I have to disagree with this one...if the car is bone stock then yes...a fmic is not necessary...but regardless...the increased flow and denser air will give a gain...although you will hit boost a tad later due to the increased volume to fill...and you don't need a bigger turbo before you need a fmic...once you start to turn up the boost even on a stocker a fmic would be beneficial...

I am seeing less power over the entire rev range...

Like even after its spooled and I have 10psi showing up on my boost guage it still doesn't seem to accelerate as quick as before.

Doesn't make much sence you would think 10psi would mean 10psi.. meaning same power but should be more because its 10psi of colder air so more oxygen.

I will have to test the cooler for leacks :P it was SOO hard to get the cooler to pipe up as I got a piping kit.. and well it didn't just pipe up I had to modify it a fair bit and it was a real bastard to get the cooler to join up.. any way thats what you get for buying from ebay.

I feel for you mate...my cooler kit definitely didn't line up too...and i had to modify my piping and even my radiator clutch fan so the the piping would fit...it might be a bitch but if you have a boost leak then you have no choice...check the hoses and hose clamps as they are usually the main cause...

What type of intercooler kit did you fit?? Is it a $200 ebay kit or did you spend 600-700 on a hybrid item?

Regardless if the car is bone stock or if its pumping 400hp, an intercooler upgrade WILL make a postive difference, as long it is an upgrade. Some of those ebay kits are really typical china crap and can have more of a pressure drop than the stock cooler and wont flow as they should, but if you got something like a hybrid you should see a gain. I just finished fitting two coolers on the weekend, one on a mates 2JZ supra and the other on a 1JZ soarer and both made noticable gains after taking it for a drive.

I would check simple things like all the fittings are tight and there are no leaks, and although it might sounds silly like mentioned above, double check nothing has clogged the inlet of the cooler (like a rag)...

Before FMIC in a strait line in first no mater what if your foot was to the floor and above 4000rpm the back tyres would light up like nothing else. Then if you shifted fast into 2nd the back end would step out and fishy tale hapily. (I have 2x 265s on the rear)

Now I get no wheel spin in 1st and can't get it to loose traction at all when smashing it into 2nd :P

Is this just because it lags more with FMIC..? I have my AFM before turbo should I move it closer to the TB?

I think you need better tyres and suspension setup.

In a stock turbo'd car, if your having traction problems its a clear indicator your tyres are worn, or of very poor quality.

As for the rest, get a tune. That will fix it

fitting a bigger intercooler should only mean a fraction more lag while it fills up the larger volume piping, but once it is boosted up it should be flowing as much air, if not more, unless the cooler is poor quality. you are showing this by the fact that rich and retard is kicking in 2psi less. i would check that a joiner hasn't half popped off.

as as nismoid said, if you can fry 265's on a basically stock car, those tyres are extremely crap, and your suspension needs work.

^ exactly what r31nismoid said..

you have 265s and still loosing traction?? on a straight line??

As for the cooler, just check for leaks and what everyone else mentioned above!!

ohh now its time for a tune!!

HAHAHA

yes my tyres arn't that crash hot i have new ones but just need to get them fitted... My suspention is all good, fairly stiff coil overs but still soft enough for a comfy ride.

This car was insane for "stock". It does have a full 3" exhaust including dump etc. and I am running 10psi but I have only had this car for about 3 weeks and you never know what has been done to these cars in Japan before they get here, could have a high flow or something.

Its probably from the 4.39:1 diff gears that make it feel like it has heaps of power and obviously more torque for each gear. 1st does neerly 50km/h when it hits rev limiter >_<

I can just take off wait till 1st gets to 5000rpm drop it into 2nd and the car will step right out and in a strait line.. I LOVE IT!

Also I think I know what the issues is. This morning I notisted the car was running rich and blowing smoke in boost so I assume its leaking so giving the AFM an incorect reading and making it run rich.

This intercooler was off my crazy turbo VS commodore :S so obviously no rags etc where in it.

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