I just installed Buschur's i/c and noticed the car doesn't boost much over 1.2 bar in 1 and 2 and by 5, it hits 1.5 and holds steady. The car did the same thing before the i/c, but now it is boosts lower in 1 and 2. I figure it is b/c of the MBC.

I am not 100% sure of the brand (bought it from a guy about 1 1/2 years ago on Evom) but from the looks of it, it is a generic one. Anyone have any other ideas?

 

I do not know the generic mbc, but does it look like this?

2 things:

1st: Check all clambs and hoses, make sure everything is tight.

2nd: Go out to a long deserted side road, pull 3rd gear. If it does not make 22 psi or 1.5 bar, then turn it up SLOWLY until it does.

Hope that helps you out.

EDIT: Forgot to mention that is a Hallman ES MBC, I have the same one, and it works great.

 

I don't have any leaks b/c boost doesn't taper/leak at all. It holds steady at the above levels. It just doesn't go to 1.4 bar in 1-3 gears.

If I turn it up in 3rd, it will up the boost for 4 and 5, which I don't want to increase the boost over 21ish psi.

 

Humm, thats interesting. I set mine to 21-22 spike, tappering to 20 in 3rd. In 5th it will hold 21-22.

Sorry I dont have any good answers.

 

Anyone else have any issues w/ the car not hitting full boost until 4 and 5 gear?

Debating on whether or not to buy a different mbc.

 

I have the same boosting in 1 to 3 gears (17psi). I have the Injen intake kit with Works P2 (boost set to 20psi) but only see high boost in 4th or 5th gear.
But, I still can smoke a STI from a roll.

 

If you have checked the gauge to make sure there are no leaks there....I would point at the MBC

 

The engine is under more load in the higher gears which makes hitting a set boost level much easier. When dialing in my MBC I usually do 3rd or 4th gear pulls as that is when I get the most consistent/solid boost. On the lower gears it will almost alway be a little less. I use a Hallman, and have no complaints and holds solid boost until redline.

 

I didnt think that I had any leaks because my boost held strong at 21 lb until redline through the gears. I did a boost leak test by this boost leak tester that I made, and wow...there were a couple of leaks. All of which were part related. Even when you dont think you have a leak, you probably do.

 

What bov are you using? My stock dv wouldnt hold boost at full tilt in the lower gears either, it was bleeding off under the pressure. When i went to the greddy, it holds boost much better.

 

Using stock 03 bov. But why does it hold boost in higher gears but not in lower gears?

 

Its hard to write out, but here are some of the factors: vacuum, boost (psi), rate of acceleration. When you are in lower gears you will climb RPMs quicker than in the higher gears. So you are pushing a lot of pressure to your stock dv in those gears (1-3). In the upper gears (4-5) the dv may be able to handle the pressure because its not getting it all thrown in at once.

A bov with stiffer springs and construction will be able to hold down better than the stock unit in the lower gears.

I was having the same issues with my stock dv. It wasnt holding boost in 1-3, but did in 4-5. Or at least in 4 and 5 until the upper band of the rpm range, then you could hear it open up. So I went to the Greddy. (Personally, I would go with a different BOV now a days, it holds boost well, but I drive on the freeway most of the time, and it will whistle at 10 vac.) My recommendation is the JDM MR BOV, its all metal construction and stiffer string rate works better than our stocker, and it will be a direct bolt on with no adjustments. But thats my 2c.

 

Cool. It makes sense. I will have to find someone that has a MR BOV in stock. Thanks man.

 

On a side note - I was at a tune meet once and this guy had a Buschur MBC on his car. The thing would go nuts.. boost would be all over the place. It really was runnin like crap. I let him borrow a spare Hallman MBC I had so he can at least get a tune done - and it worked like a charm. Maybe Buschur MBC's are that great?

 

Anytime. Here is the link for an upgraded version of the JDM MR bov. Its made (rather modified) by Tomei. They upgraded some internals, and made it that much better for us. I have seen some good stuff said about it.

Here is their info:

http://www.tomei-p.co.jp/_2003web-ca...bo_outlet.html

Lancer Shop has them in stock:

http://www.lancershop.com/customer/p...&cat=27&page=1