Hi,

Before I install my HKS RS intake my EVO IX run on 1.2 bar it was great, then I installed the HKS RS intake in my car the car is run 0.7 bar, I don’t know what happen but I check every pipe it’s been correct.

What should I do to solve this issue?

 

Tune! The HKS intake gets the best gains and benefit from a tune, as it leans out the whole system without one.

 

but why the car run in 0.7 bar after installed the RS intale? that is the qustion.

it should be same before 1.2 bar

 

Did you keep your stock vacuum hoses that run from compressor housing to wastegate actuator? or use new ones that might have come with the intake?
There is a restrictor pill in the stock hoses. .7bar is about what you would get without the restrictor pill.

 

i kept the stock vacuum hoses

 

do you think the stock vavuum hoses is the reason?

 

Dud you need a tune. Without a tune the car runs better with the stock parts. I got that information from one of the best tuners on the East Coast, Sean Ivey. I have the same intake.

 

He's saying IF you removed the stock vaccum lines, that's the reason. There's a little restrictor pill in the stock vaccum lines- It causes the car to run more boost than just a regular vaccum line. So if you replaced vaccum lines, that's the reason.

But yes get tuned asap to see any real benefits.

 

I change the vaccum hose and still run 0.7 bar.

What should I do?

 

After trying the obvious alway work your way backwards through your mod or project. My suggestion is to put the old intake back on and see what happens. Quadruple check all your connections to your boost control selenoid. If all else fails go straight to a technician or tuner who knows Evo's.

 

1Bar= what 15PPSI? 0.7 bar has got to be around 12PSI which is also happens to be the stock wastgate pressure. First thing to do is purchase a Manual boost controller and Boost Gauge. Once these are installed turn up the boost. Also make sure that there are no boost leaks especially around where the BOV is installed on your new intake, that could be a BIG issue as well.

But since you are at exactly Wastgate pressure, my guess is you need a boost controller.

You are using your stock Boost controller which is now being told to LOWER boost as there is a LOT more air entering your engine. Get a TUNE. It'll fix everything with the Boost controller.

 

^^ I'll echo that, mbc/gauge and tune time

 

Great minds think alike.


In your tuning experience, how much does the HKS RS intake mess with the MAF readings and lower the boost consequently (Stock Boost Control Solenoid in use)

 

100% of my customers do a mbc/ebc + tune at the same time they do an intake so I don't think I have that data.

 

Boost leak at the BOV hose.....

Get the car tuned asap. I'm sure there is someone local to you that can go over the details under the hood before your tuning session.

Cheers!!