I could be that your stock valve was working perfectly or..... your new MR DV is defective

Anyway, changing the DV is no guarantee that you'll get more or better performance. It worked out that way for me, but I'm not surprised that it would not work out in other cases.....

 

For grins I did a boost leak test tonight......and I tried both DV's.

The stock plastic DV started leaking at 18PSI but it didn't leak very much. Just a slight hiss. It got louder with more pressure.

The JDM metal DV started leaking at 24PSI but once it started to leak it was much louder than the stock one at 18PSI. Both sounded about the same at 24 PSI.

Conclusion.....I doubt you will notice a difference because the turbo can easily overcome the minor boost leak caused by the stock DV at 18PSI. Non-the-less....a boost leak is a boost leak.

 

My stocker opened at 13psi. There was no audible sound yet, but the air was leaking out when I put my hand up against the intake outlet, which means the valve was opening already.

 

I purchased a used one and put it on my 05 car. Works perfectly. I definately notice a difference at 5-7k rpms where it would keep pulling bit more over stock. No stutters, no surging... works perfectly for me. I'm also running an AEM intake with it. what's really nice is with the Intake i have run both Stock and MR DV. With the Stock i would notice more "sucking" noise from the intake. With the MR DV i wouldn't hear as much "sucking" noise (air leak now that i noticed a difference between the two) just Turbo whine throughout the Rpm range.

 

I just installed this valve. The MBC was set at 21-22psi with the OEM plastic DV. After I swapped to the MR DV, the boost spiked to 26psi (the MBC was untouched) and I hit a boost cutoff. I'll try adjusting my MBC again tonight, but I didn't expect the boost to spike that high.

 

Anyone with a dyno chart before and after MR BOV?

BTW, no probs with MR valve...

 

any bodys rpm dip when u install the mr valve. meaning did the car almost stall sumtimes. how much boost can it hold? In differences with the tomei bov.

 

I just installed an MR valve. THere seems to be some lift throttle stuttering in 5th and 6th, but this could be because of the XEDE. It's not really a problem though, and I can't really but the blame on the MR valve because I don't know if it's the culprit. It certainly holds boost better, though

 

I have a question about the JDM MR DV. I have a turbo back exhaust on my 05 EVO. I will be taking the car to the road course soon. Would an MR DV be helpful in the frequent high rpm driving on a road course? Should I invest in one just for the sake of leak safety on the track?

 

If your OEM valve is working well, there would be no advantage to changing it....

 

Could you please explain to me how do I go about testing for leaks. What tools/methods do I need?

 

Most people have determined that the stock plastic valve doens't hold boost above 15PSI.
If you are running 20+ PSI it would be wise to upgrade to the metal JDM MR DV.

I have and have had no issues. However, I really didn't feel any gains either. Its just nice to have a piece of mind.

 

Some people have noticed that the plastic valve does not seem to hold boost levels as well or as high as the aluminum valve. I would not say that the plastic valve cannot hold more than 15 psi because I've seen well over 20 psi boost spikes with the plastic valve...... Now, I did notice that the boost gauge seemed to hold the boost a bit longer or higher with the aluminum valve than with the plastic one... No way to really tell if it was a placebo effect or what. I have not done a controlled scientific test to compare them, but I remember I was really excited about the aluminum valve when I installed it

 

I didn't say it would leak all the boost just some boost. Boost spikes are a different animal.

Unless you are hardcore I wouldn't worry about it.

 

Sorry very late entry, but I will give my input to this thread, I've gone from plastic stocker, to Greddy Type S (single spring) and soon to the JDM MR DV. Got the DV for cheap so thought I'll see if it'll be any difference to the Greddy at least.