Otto-Mate

Hope to collect my MY03 STi on Friday :-D

So, whats the story with the water spray switch? When do you use it?

Is it possible to download a PDF of the manual for a MY03 car from somewhere?

Thanks

M.

CRAIGFIN

Otto-mate,

Its not 2003, but its very useful, click below...

2004 STI

Craig.

pslewis

You use it in the MacDonalds Car Park when the Chavs are looking!!!

It's pretty much for 'show' .................... don't do an awful lot that would help you on the normal roads!!

Pete

pippyrips

intercooler spray - simply sprays a jet of water overthe intercooler to help increase airflow. Read on hear all sorts of reasons why to use it but basically use in hot/warm weather. I have an automatic setting in myJDM but don't think it is fitted to uk specs?

pslewis

It actually adds that 0.25BHP increase to enable you to carry the water tank for the sprayer without any penalty over a car without one!!

Like I said .............. utterly pointless, but, if you feel good with it - why not??

Pete

Otto-Mate

Thanks Craig (and to the rest of those that replied).

Is it possible to get that as one big PDF? Are there many differences between 03 and 04's?

/me is looking forward to the updated FAQ

Thanks

M.

stevie boy

use it before an overtake or anticipated heavy right foot moment.

blow on your finger, then lick it and blow on it, colder right??

as the water evapourates it cools the i/c, the colder the i/c the cooler the inlet charge. to wait until you boot it is too late

the auto button on jdm's is only any good for prolonged heavy driving as it cannot predict when you are going to boot it, so you should still pre cool with the manual button before you gun it.

stevie

johnfelstead

The Auto function is ECU triggered based on boost, turning the Auto switch on enables this ECU functionality, which when on boost sprays the IC in 5 second bursts.

The IC spray is there to help reduce charge temperatures, it helps drop charge temps quicker if you have been in standing traffic in particular. It does make a diference, the main benefit being reduced knock correction due to high charge temps.

It's not going to turn the car into a rocket, but it will provide safer charge temp control on hot days, i only ever used Auto mode on track and used manual mode if stuck in lots of standing traffic and the charge temp guage was going balistic due to heat soak into the TMIC.

The safest way to drive these cars in standing traffic is to not nail it from standing still if you have been stationary for a while, but get some airflow going through the IC first, the charge temps drop quickly once on the move, this drop is helped with some water.

JTaylor

John (or anyone else qualified)

Is this less relevant with a FMIC. I/C waterspray is on my to do list.

Thanks in advance,

J

johnfelstead

it depends what you want to achieve, but at sensible power levels and use a FMIC doesnt really need water sprays to the same extent a TMIC does. It's a big help on rally cars with a FMIC, but they are constantly on boost and at acute angles to the direction of travel, although the latest WRC cars dont use IC sprays as they have very eficient airflow and cores now.

JTaylor

Thanks John - that stacks up. I don't spend much time drifting through the forests so I guess it'd be overkill. I'll spend the money drifting someone elses car through a forest with a brave instructor next to me.

Just out of interest what times have you posted at Castle Coombe (Tarmac)? Local lad Carl Sorenson's been doing early 1.20s in his standard STI 9 and I'm up there on the 16th September. Your name cropped in conversation but neither of us new what times you were setting/had set.

wide

So when its raining does the same theory occur???????????

pslewis

PMSL this is BRILLIANT!!!!

Only on ScoobyNet could you get grown men talking about spraying water over the intercooler to gain an imaginary increase in power!!!

Have I told you lately how SAD you all are!!??

Tears rolling down my face at the thought of some sad loner in an Impreza trying to push the water spray button, while they try and keep an eye on the CockLink, also attempting a tricky gearchange manouvre according to the dip**** 'change gear NOW' light .............. with a pair of Det Cans clamped to his ears and a spotty geek sat next to him with a Laptop trying to fix the plaster fixed NHS glasses he's wearing

Stop it now ................. my stomachs aching!!!

Pete

sammyh

iTrader: (1)

Pete, would there be any chance of you posting something constructive for a change?

Nick Read

LOL I can picture the scene myself. But on a more serious note, my understanding is that IC water spray is not used to increase power. It's to try and combat LOSS of power through inefficient charge cooling, for whatever reason - hot weather, crap airflow through the IC, heat soak at low speeds or from long stretches on full boost etc. It's more necessary on a Scoob because of the fundamentally flawed location of the TMIC. Careful front mounting of the IC would alleviate most of these problems and mean that water spray was not necessary. But then with a more stable, colder charge temp, you could tune for more power, and eventually might find the need for water spray function again when you got close enough to the capacity of the FMIC.

Basically water spray is a factory-approved bodge, but a good one that gets round the restriction of having a TMIC in a fairly simple way with no real downsides for a road car. When rallying every kg counts and you might need to carry say 20 litres of water to run the entire stage at your chosen power output; that's when you have to start looking at the weight of water vs. the additional boost you could safely run using water spray. I've not looked into it in depth, but I'd imagine if you're going to carry 20 litres of water around you'd be better off using it for water injection rather than water spray. IMHO

STI Craig

wer sad ??????
your the one that lives on this site!

anyhows the only thing i noticed with the water spray was it helped a tiny bit wen i had been sitting in trafic on a hot day for 1st gear only !!!!

nik52wrx

I think he's funny..............

JTaylor

Hilarious Pete, lmfao

JTaylor

In a cold damp atmosphere our cars perform far better then in blistering heat.

JTaylor

Spot - on.

Tripple'O G

Can you hear anything when pushing the manual switch?

I mean anything to tell you it's actually working???

and ha ha my first corner

Sinister Subaru

It's mostly gimmick, but it supposedly helps to cool the the intercooler while hard-driving. When I use the intercooler sprayer, I can feel MAYBE a slight "lurch" in power if the intercooler is boiling hot, but I think it's more of a gimmick than anything else.

I just enjoy having the thing just for giggles. It's fun to push buttons and feel like you're actually doing something.

Sinister Subaru

With mine, you can. It makes sort of a "buzzing" sound, almost.

pippyrips

if you really want to know if it is working - open the bonnet. You will notice a pipe running to where the vent is on the bonnet. Push the button and you should be able to feel the spray - as simple as that

Tripple'O G

Cheers, i'll have a squirt and look later......

(or should that be a look and squirt?)

Chelspeed

It's very straight forward. On rally cars it was useful to control charge temperatures so they wanted to fit one. Homologation rules didn't let them fit any performance enhancing mods unless it was on the road car. So the road cars got intercooling sprays.

Homologation only covers whether it's fitted or not and the method of controlling it is free. So rally cars get expensive ECU control of spray but road cars get a cheap manual switch.

Is it useful on rally cars? Yes, otherwise they wouldn't lug the weight of the water round. Is it useful on road cars? No, it's there for homologation purposes.

Otto-Mate

What's "charge temperatures" please?

Thanks

M.

Chelspeed

The temperature of the "charge" entering the cylinder before it "explodes". In other words the air temperature after the turbo compresses it.

The intercooler sits between the turbo which heats the air (as a side effect of compressing it) and the engine which likes cold air and tries to restore the air to a more favourable temperature before it reaches the engine. Some places actually call the intercooler a "charge cooler".

Why does the engine like cold air? The turbo can only blow a fixed volume of air into the engine. As hot air is less dense (has more volume for a given amount of air) the turbo will be able to blow less hot air into the engine than it could if the air was cold. As power is made by burning fuel with air the more air that is in there the more power. So the colder the air the more power!

Brun

***Thread hijack***

sammyh
Senior Moderator
Join Date: Feb 2000
: Newport Wales land of sheep and all things woolly
Posts: 15,761

What does the senior bit do for you? Just spotted that

Otto-Mate

Thanks Chelspeed

M.