Just hooked up a boost gauge today (autometer mechanical), and my max boost is 17 psi, and immediatley begins moving between 17 psi, & 15 psi, moving back & forth over & over.

The only mod I have is a cone filter and a GReddy RS bov (which the bov came with the car). Am I leaking boost through the bov? Thats what im personally thinking. I get compressor surge all the way up to 6000 rpm too from the bov being so tight... but if I loosen it up anymore, the car dies. I NEED a stock diverter.

 

That's not far from stock boost, and you have some crappy mods that screw up the car, so get those remedied and then see how it behaves. Start by putting on the stock intake and stock bov. Borrow them from someone if you have to...

 

My car has been flashed with a base map too.

 

Then the intake is ok to keep as long as the base flash was for the intake, but you should slap on a stock BOV (or other good BOV) to see if the boost keeps acting funny.

 

+1+1+^^yup^^+1+1

 

i got almost the same issue, with my stock IX, i peak to 20psi wich is what Mistu says, and then it tappers down to 15-17 psi, now someting i learned is this only happens when my car is not under full load, for example 3rd gear pull i will hit 20 psi then come down to 15 steady, now on the higway 4th and 5th i will constant hit 17-18 psi.

experts what do you think ???????

 

In higher gears you get a higher load so your boost wont taper as much.

 

very true, i understand that,

what are guys in here doing to maintain boost.?

 

LOL. The expert Evo gods are saying "learn your car!" Your car is fine as stated up above.

 

Using a boost controller? Was that a legitimate question?

 

On stock evo 03 without MBC, when you hit boost above 5k rpms it will drop to 15-16psi which is normal, get MBC to hold the boost steedy at 20psi, no need to replace your BOV.

 

Not to mention its not uncommon for the autometer (or any guage for that matter) to be off by a couple of pounds on boost. About the most you can hope for is that its consistent.

On my autometer, it was off by over 2 pounds. If it read 20, it was really 22.

 

I know about 'taper'. This isnt my first boosted car. Im interested in knowing if the GReddy Type RS has had problems with not holding boost... I cant even get a spike at 19lbs like im supposed too, just a measly 17 psi.

 

MBC will help reduce taper

 

No ****? You mean to tell me I didnt know this? And I didnt read all the responses from this thread? And thats not even my concern! 17 psi is not 19 psi, which is what it should be.

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