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Originally posted by Works Auto

When i had my stock turbo and i put a Hybrid front mount on, trust me when i say "it didnt go slower "  

It picked up alot of power.

rev210 i think thats total rubbish and i duno how you can back up your claim. The cooler the air, the denser the charge = power.

Yes the colder the air, the denser the charge = power is true. But , the longer the pipe and the greater the volume to fill, the longer the time taken to reach piston = slower engine response time (note I did not say anything about lag).

Turn your hose on and see much longer it takes to fill a 15L bucket Vs a 2L one at the same hose pressure, thats the difference in volume between the GTR cooler and the stock gtst one from memory. Sure the air is colder and the engine makes more power, it just loses time in getting to the same rpm.

If you'd like to tell me how making the air path 'longer' increases performance I'd be interested to know too.

I don't think you are suggesting that making the intercooler pipes do two laps around the car body would help. The principle is the same on the larger volume intercooler although the magnitude is less ridiculous.

You may be missing my point. The 'power' over a stock unit I have never disputed. My issue is the possible response time issue introduced by the greatly increased volume of the new intercooler and piping.

Here's how I back up my claim alternatively :

Let's see a front mount intercooler equiped R33 gtst with a stock turbo run better than a 13.3 @106mph on 205's. To the best of my knowledge there isn't one.

I'm not trying to poo poo aftermarket intercoolers, I'm very sure that you can do much better than the stock unit, it's just that for the extra expense you need to make sure the size is 'just right'.

Someone should do some calc's.

We need to work out how much extra volume a FMIC (including pipework) has over a stock one.

Say if it's an extra 20lt, then we can work out how much longer a 2.5ly motor will take to fill the space.

Say at 6000rpm and 2500rpm (where people change gears, and the rough spool up area for a turbo - this is rough).

The motor will push out 2.5lt of air for every four rotations. So at 6000rpm the motor is pushing out 2.5lt of air 1500 times a minute, so that's now 3750lt of air every mintue.

So now we need to find out how much time it'll take the motor to fill this extra 20lt of space, when the motor flows 3750lt per minute.

Am I thinking on the right path here?

OK - my brain just reached it's limit (I'm on holidays and my brain is in life-support mode).

Jay95R33,

I think sydneykid did some calcs some time back on the same subject.

I say this thread should be moved to the forced induction section to allow more participation in the debate.

zanda,

if he has that time at the plex and not a g-tech then I conceed he has a better time and for the time being a faster car, he probably even did his pass on 165 tyres :) I guess that just leaves me with the fact that I haven't blown the best part of $1.5K on an intercooler to go 0.1sec faster (he is still faster so I'll have to suck eggs).

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