rsboy

iTrader: (48)

Agreed. My stock bov holds boost just fine. I actually had the Forge bov on, but couldn't stand that damn stuttering in half throttle. I just took it off and now totally enjoy the smoothness of the stocker, again. I'm also using the Buschur mbc and I boost up to about 1.45 bar on 4th and 5th and it holds fine. I'm not really planning to boost more than 21psi so what I have now is pretty good.

Shaker Motorsports

iTrader: (17)

I have been flashed it makes little difference if your bov is leaking. Maybe you and 4rcd6 have the only 2 non-leaking factory plastic BOVs.
Let me explain. A BOV is a sping acutated pressure relief valve. It works be relieving pressure over a certain level. You can send this excess to the atmosphere or recirculate it. The factory BOV recirculates the pressure back into the intake plumbing. If the spring begins to release pressure at 21 psi, that would mean that the valve would just start to open and release the air but as you continue to produce the boost the valve would open slightly more. This would cause a greater loss of boost. The boost level will taper and then hold at a level that is defined by the amount of space the plunger in the valve is opened. If the top of the plastic bov has any leaks then as the boost grows you will lose more pressure and cause greater power loss.

If you replace the BOV with a better, even stock JDM is better, unit that doesn't leak and is designed not to release until a higher psi, you will not lose performance and will better maintain boost levels.

Also, boost controllers have small holes in them to bleed off excess pressure. The basic TurboXS has a HUGE hole. It will bleed worse than a Hallman or turboxs high perf unit.

Any questions class?

BLiu

Since we are in class, you might want to do a survey on how many people ACTUALLY can quantify how much boost is truly leaking from the stock BOV at 20psi before you make that assertion.

Just because you know how to describe how a BOV works does not make you an expert to solve a single case using your own outlier data.

No need to get defensive and talk down to people, even IF his BOV is leaking, that is NOT the worst of his problems. Having an aftermarket intake and a full 3" exahust without ECU tuning is a far more pressing issue that needs to be resolved then a "leaky BOV" which you have accurately diagnosed and explained to us in your "class".

If you calm down, you know yourself, that his first issue is to get reflashed before anything else. Honestly, don't tell me you wouldn't advise him to first get reflashed because that has FAR MORE benefits for his money and maybe, just maybe, his boost leak might be resolved as well. Heck, even if he STILL has a boost leak of 3psi, he won't freakin CARE because he will be LOVING his reflashed ECU and how his car will be running...

No one is questioning your suggestion, just the fact that getting a BOV should not be his first solution path knowing that he still has a stock ECU. And please don't bring in the warranty issues because he is already down that dark path and he can always get reflashed back to stock if he needs to.

We, in the evo community want to try to help each other especially since this is already a PROVEN path for mods for a LARGE amount of evo owners on this forum. I don't see why you need get so testy....

Maybe you need to punish me and send me to a corner...

PS It's now THREE people who have no problems with the stock BOV...

Brent

Shaker Motorsports

iTrader: (17)

You have anger issues. No one was defensive or talking down. I was addressing his question, he never asked for input into his other mods. Truth be told, he should take out his intake put back the factory airbox and a drop-in K&N, get flashed and not put the intake back in until he really needs it.
No, even Al will agree, that before he gets tuned he needs to replace the stock BOV. This is a major flaw with the system and should be replaced as one of the first mods.
I am trying to help but too many people like yourself are just looking to argue invalid points. His BOV is a major problem, his intake is a major problem, his exhaust isn't a problem.
I tune cars and race them, I have for a long time. We can continue this discussion in Ohio at the shootout or at Englishtown the week after, I'm always happy to help another enthusiat.

If you are going to take a shot at me at least know what you are talking about.

And nyrican, I will happily help you via PM so that your threads are hijacked by people not specifically trying to help you.

4rcd6

iTrader: (7)

Well to a point.. your right about not needing the aftermarket Intake.. a drop filter will sufice for what its intended for. Although thats not what most ppl do since the appearance of it and sound quality enhances. Getting flashed is what its all about.. and when Al custom flashed my evo, he never mentioned to me the bov is any concern to the performance of normal bolt ons. I run 22 psi and drop to hardly 20.5 at 7400 rpm. The original question was about losing boost and if there was a problem.. The problem is that he doesnt have a flash and you know that. No reason to try to boost your ego and try proving ppl wrong vs your "correct thinking".

I'm sure that getting a different BOV will help in small margins, but its not going to fix the problem he still has at hand. Even with a MR or Type S bov there will still be 3 or 4 psi loss with that as well. Its not worth spending 175+ for a bov if in fact its going to give him the same issues hes complaining about.

You have valid points, but your thinking outside the bun(taco bell) and there is no reason to do so. So many ppl in here try to one up another instead of making others know its a true valid statement that he truely needs a flash. I'm putting money on that fact if he were to get a flash.. his problem would be gone with the stock BOV.

Shaker Motorsports

iTrader: (17)

I promise you that is you get a replacement BOV, you will notice the gains, with the JDM I never lost more than a 1 psi all the way to redline.

If he gets the flash and his BOV still leaks, then he will still be unhappy with the loss of power.

Al won't make you repalce the stock BOV but ask him about it. It is the first thing to get replaced along with the MBC.

Hey, I'm not making any money on this thread and am in the process of becoming a vendor on the site. You have no reason to trust me but I have no reason to mislead or lie.

Peace and love brothers and sisters.

grcygetr

iTrader: (1)

Hallman MBC Pro, stock BOV etc...
Boosts to 21, holds til redline. It may taper 1/2 a PSI...but it's really not noticible

Guess I'm the 4th with a super-duper-non-leaky stock BOV

It held up to 23PSI with no problems while we were setting the MBC, no taper

BLiu

Nyrican, we are trying to help you and NOT hijack a thread regardless what other people's opinions are...

Given the fact that you have an intake and an exhaust, I am sure you don't want to take it off and waste money and put in a drop in filter as a solution...

Also, you have already ordered the Hallman MBC so you are getting rid of the TurboXS piece (I have had no experience, but as others have contributed, the TurboXS may not be a great piece to begin with).

So, your next mod, eg, the best path if you are planning to spend some money should be to invest in a reflashed ECU. Heck, you are even planning to add the Walbro fuel pump, which means your car is BEGGING for an ECU reflash because you are right there with all your mods....

Some of us actually read the post thoroughly and try to best help your situation as you described it....I don't think that's THREAD HIJACKING is it?

Then, if you are still unhappy with the boost taper, you can TRY to get it resolved by an aftermarket BOV - word of warning, a lot of aftermarket BOV's don't work well with the Evo and I am sure our "teacher" failed to mention this in suggesting you get an aftermarket BOV. EVEN the JDM BOV has given people problems and you can search on the forum for that information as well.

I don't need to give a lecture on BOV mechanics or tell you that I have "tuned cars" to lay out the logic. A 3psi boost taper to redline is not the first thing you need to address at this point and I am sure you don't have money to burn...

In other words, the loss of horsepower you are getting from your 3psi boost taper is probably less than the amount of HP you are NOT getting from an ECU reflash. If you are into more HP for your money, then an ECU reflash SHOULD be the next step. Like I said, you already committed to the investment of an intake and full TBE, you might as well spend the next dollars on an ECU reflash vs. a BOV replacement.

I think that's pretty logical and I think I read your post correctly and thoroughly, BTW, who's angry????

Brent

BLiu

And I promise you that if you get an ECU reflash, you will notice EVEN more gains...which would you rather spend money on next? Seems logical right????

As for the JDM MR valve as the solution to boost taper, here is a thread with a lot of interesting opinions - most love it, but there were a few who did not:

https://www.evolutionm.net/forums/sh...ght=JDM+MR+BOV

So...can we be excused from class now?

Brent

Shaker Motorsports

iTrader: (17)

Brent,
You are amazing.

That's right if you get flashed you will noticed some gains. You will also not a gain if you go back to your stock airbox and a K&N drop-in. I'm done now as some people aren't very mature.

Thegame

iTrader: (26)

I have a Hallman Pro Rx tapped into the turbo outlet. I actually bought the JDM MR DV before I got the mbc, but I did notice that even stock, the MR DV just felt different in a positive way. After installing the mbc, turboback exhaust, intake, etc, I set it to 20.5 psi and it tapered to about 17. I thought I might have had an ic pipe leak so I bought some t-bolt clamps. Now my boost hits 20.5 and falls just a bit to about 19 by redline. In my case it was a boost leak causing the dropoff. In your case I would try a differnt BOV, boost leak tester, or a different mbc. One other thing; I never get boost "spikes." Is this because of tapping the boost source off of the turbo outlet? Good luck with your boosting.

4rcd6

iTrader: (7)

Is your ECU flashed?

I never changed a thing except put on MBC after my custom dynoflash. My boost is set at 22 and settles at 21 maybe 20.5 worst case senario. I do like you've read use the stock GSR BOV. Not to say your senario doesnt have value, but you could have had an issue with yours. It is possible it was a fluke.. but if you ecu is flashed.. its the difference maker..

05-EVO-GSR

iTrader: (16)

This is normal. There is no boost controller that will hold rock solid boost till redline. As long as it is solid up until 5,000 rom, the boost controller is fine.

nyrican

iTrader: (4)

Damn , thanx for the wealth of information, and I once again apologize for not informing my whole story , with the new MBC and fuel pump on the way I ABSOLUTELY intend to get a custom tune to go along with the mods. I guess I have to wait till the parts get here, install them and then drive down to TT to get tuned before I figure out whether or not the BOV is leaking enough for me to replace it. I personally do not like the idea of running an aftermarket BOV because it seems that most people actually have more issues with them than with the stock ones. I do not plan on boosting anymore than 22 PSI so I hope I can keep it, or at the most go with the JDM MR one. Thanx again everybody. OH yeah I did hear that I might lose power with the intake before tuning but AFTER the flash it should be just as good or better than the stock one, right???

05-EVO-GSR

iTrader: (16)

Explain how the "boost flash" will hold boost if he is using a manual boost controller?