Boost Cut

[MattMPS3]

No reason you cant, the turbo is just starting to run out of its efficiency window the higher you go, maybe see what your tuner thinks. There is a theory that after 22psi (@ turbo) there is a world of hot air rushing out of there.
Are you running an aftermarket intercooler, a reduced pressure drop from the turbo to the manifold will allow a bit more boost ?

[MS3]

No reason you cant, the turbo is just starting to run out of its efficiency window the higher you go, maybe see what your tuner thinks. There is a theory that after 22psi (@ turbo) there is a world of hot air rushing out of there.
Are you running an aftermarket intercooler, a reduced pressure drop from the turbo to the manifold will allow a bit more boost ?

Yeah mattmps3, my car's front mounted. I also don't plan to always run on 21psi due to petrol. My other map i'd like to just be running 17psi maybe 18psi.

Basically i will be changing turbo's on the car in the future, probably stick to the KO4 still but a high flowed one. Just don't want the turbo to go pop during this year though, it'll be a pain if that happened.

Looks like i'll speak to my tuner, and ask them about running 21psi

[Nuliaj]

If you're planning long term and a big turbo isn't in the plans, running higher boost will reduce the longevity of our turbo, especially as it really isn't designed to run high boost. A reworked K04 would allow you to flow more without having to boost as high as well as letting you keep the low rpm responsiveness of the K04.

Edit: Bah our damn proxy went down and your response went up before mine.

[MattMPS3]

In all honesty I really don't think you'll find that much benefit from an extra 2 psi, as I'm sure you are aware the secret with these engines is the timing adjustments for power increases. Hence the reason meth kits are so popular in the US.

[Nuliaj]

While debatable, the vendor dynos show a 10-20hp gain just by swapping to a reworked K04. Push another 2psi would net another 20-30hp which doesn't include tuning.

I don't know too much about the gains with WMI, what are the typical gains these days Matt?

[MattMPS3]

Ahhh, yes but the rework flows 35% more CFM, its more about the volume, not the pressure with these units, different kettle of fish all together there.

WMI, on a car not specifically tuned for it will do very little power wise, but is a great insurance policy as the water meth increases the octane of the fuel by ~8 points, so 98 octane + 50/50 water meth will yield a theoretical 106 octane, the other benefit is the cooling of the intake charge, its essentially chemical intercooling, so the benfits of a denser / cooler intake charge still apply, i.e the car will adjust its timing to benefit, e.g car will run like it does mid winter, in the middle of summer. Typical results are BAT's lower than IAT's....sometimes even lower than ambient.

If you are tuning for it you can pull a lot more timing due to the benefits of the higher knock resistance (octane) and make some bulk power, although you woud want a pretty hardcore setup for this as a clogged nozzle could lead to BOOM!

[EQ]

....kinda technical....I was with you upto and including MAP clamp....

[Jmac]

Good information, Stickied