Replacing the Stock WRX intercooler?

[Richard L]

it will be interest to what is registered. You can tune the back ground noise out and hopefully only knock is indicated. I am not expecting you to tune all the noise out unless the engine is underload. Reducing the boost to wastergate pressure might is more realistic.

[mrex180]

Not a bad idea i'll change the hoses around and check out what it does..

[JohnA]

True, KnockLink is known for being unable to distinguish 'normal' engine noise from real knock at revs as high as that.

One way to 'calibrate' it is to do a run with race fuel and same boost/WI conditions and see what KnockLink shows. If it still lights up, then you know that it is NOT knock.

If it doesn't light up with race fuel then "oooops" :wink:

[mrex180]

Ok i run the turbo on wategate pressure only which was 7psi from 3600 to about 5700 but it crept up to 10psi at 7000 (looks like the gate could use a bit of porting) and it was virtually the same a before with the knocklink, i then did another run trying not use any boost and i got 2 greens and 1 flickering orange up at 7000, Please tell me if i'm wrong here? thinking it's only background noise and i can't here it pinging i ended up taking 1/4 of a turn of sensitvity out of the knocklink, so it only started showing green leds at 6800 and 6900 oranges and red at 7000. I'll probably get my tuner to set it up properly on the dyno though when i get 18psi - 19 psi out of the turbo.Oh and the runs were all in 2nd and 3rd gear....

ANdy

[JohnA]

I've found that KnockLink is very sensitive to the location of the sensor relative to the engine.
Also the coupling of the sensor can have a major effect on false alarms, just as the tightness of the bolt that keeps it in place.
Try using aluminum or copper washers, and alternative locations on the block or cyl head. You never know where the ideal spot will happen to be, it takes experimentation.

[mrex180]

Thanks John, i just picked the old TMIC bracket hole on the left hand side of the block which is on the opposite side to the other knock sensor the car that ecu uses, i picked it as it seemed to have the most surface area that i could see as the other holes were rasied above the block a little and only half the sensor area would be in contact with the block.

[mrex180]

Trying to get my head around this maybe someone can have a go at answering it ?now i know WI won't remove as much heat as my factory IC did with WI BUT because there is little restriction in the intake path now will the gain in flow and less exhaust back pressure still be benifical and i'll will i gain power and response ? or because of the added heat will the power drop off to below what i had before??

Tunings still a few weeks away yet and i'm curious as too which way things will go?

Andy

[JohnA]

The effects of WI will depend on how close you are to detonation otherwise.

Cooling the intake is not what WI does best. It will do it to a degree if there is no intercooler (so the air temps will be very high) but most of the real work is done inside the cylinders, once the compression has started.
That's when the water droplets will become steam and absorb lots of heat in the process.

If you want to bring charge temps down to ambient (or close to that) then best is to use an intercooler. WI takes over later.

[mrex180]

So John whats best to look at then EGT rather than IAT with WI?

[Richard L]

I agree with John on this, water can evaporate as much as it is allowed within a closed environment. Once the relative humidity is reached, it will stop cooling.

It is a completely differently set of conditions when it enters the combustion chamber - water is 100% effective as a coolant.

Richard