damn u joe p!!!!!!!!

[lowridin2g]

well ive been having like randomn boost hesitation ever since i installed the joe p mbc. so i take it out tonight and what do i see but a pin hole in the actual T fitting that the mbc is made out of. seriously !!!!!!!!! who the F does that? i have the worst luck. now i have to find some way to plug it. blah. just had to vent. and if anyone has any suggestions on what to plug it with i would apreciate it thank you.

 

[Bohrn]

there is supposed to be a small hole somewhere in the body of the unit. ALL mbc will have vent in them somewhere, JoeP, Hallman, Busta, or even the one I made for less than $15 bucks.

Do the research, you will see.

oh, don't block it. It is there for a reason. Without the vent, the check ball will not be allowed to seat at the boost end and thus not close the circuit when the correct conditions are met(you lifted)

 

[lowridin2g]

alright i didnt block it. but ever since i installed the mbc i get boost hesistation every now and then mostly at part throttle. but it def. leaks. i teed in a line to the bov hose that goes to the intake mani. coming from the bottom of the mbc. coming from the side i went directly to the wastgate nipple. then i plugged the nipple on the turbo, and the nipple coming off the intake. i left the bcs plugged in at the bottom but i plugged the nipples on it. should these holes be plugged and if so would not having them plugged completely cause what im getting? please help, im going crazy

 

[Bohrn]

take out ALL the stock vacuum hoses associated with the boost control unit. You should keep the bov line stock tho, so replace it with an uncut piece.

Then attach the turbo outlet nipple(on the j-pipe that goes to the intercooler) to the bottom of the mbc. Next attach the side of the mbc to the wastegate. These are the ONLY hoses you need. The boost control solenoid and all its associated plumbing can be disconnected. Put a cap on the intake pipe nipple(right near the aircan, slightly leaning forward)

You dont have to get a new hose to the bov, but I like to keep things simple, and also there is less chance of a leak with less fittings/cuts in the lines.

Another good tip is to keep your hoses as short as possible. Under 6" is best here. I have my controller mounted on my fan shroud. Don't worry its good and solid. The shorter the hoses the less boost spike you will get. I had it mounted at the location of the bcs originally, but I got 3-5 psi of spike. Now with the inlet hose about 5" and the outlet hose about 7" I get 0 spike. Its a big deal, knowing you can floor it, lift for a second and floor it again, with no danger.

Good luck.

PS, next time, do a little research, you will find all this info, with pictures etc. The reason I say this is that some of the people here will be downright mean about this and not help ya.

 

[lowridin2g]

thanks bro, so what ure saying is just run one uncut line from the bov nipple to the intake mani and use the turbo outlet nipple to coneect to the bottom of the mbc as a boost pressure source? then cap the intake pipe with what? like what would u reccomend? thank you again u have been very helpful

 

[Vinnie]

go to my website, I have directions in how to install a MBC

http://awdpower.tripod.com/talonperformance/id20.html

 

[lowridin2g]

well i rerouted my mbc line that teed in at my bov line. i went directly to the nipple off the compressor on the turbo. no boost hesitation so far. knock on wood.

 

[doug]

That should work well for you-- good luck with it. That's how I have my MBC routed and it works great. And you don't need to cap off the BCS nipples, but you do need to leave it plugged in electrically.

 

[Bohrn]

not talking about the bcs nipples. Of course those can be open. I'm talking about the nipple on the end of the aircan, just before the rubber intake pipe. It leans forward slightly and is on an angle towards the engine. It would allow unfiltered air in if left uncapped.

And as for leaving the bcs unplugged, I have had mine unplugged for 6 months or so, with no adverse effects. Most all people who have aftermarket upper ic pipes have it gone, as the place it sits must be removed for the pipe to fit.

 

[doug]

Yes, I understood you meant the intake nipple to be the one capped-- sorry if I was unclear. And yeah, on 1Gs you can unplug the BCS, but on 2Gs, most will throw a CEL if you take it out, I believe.

 

[Bohrn]

so what do all the 2g guys do? I see lots of pics of 2g cars with no aircan, etc?

 

[doug]

I'm not sure I understand your question. 2G guys cap the intake pipe nipple just like 1Gs and remove the boost control solenoid hoses, but just leave the BCS itself plugged in electrically.

 

[nine5raptor]

borhn,

the 2g bcs is much lower and out of the way, so we don't have to worry about it with uicps.

 

[MaineDSM]

I've always thought that pinhole was there to alter the amount of boost spike and spoolup lag when you initially hit the throttle.

If the hole is too small, the pressure will hit the wastegate too quickly. This will cause the wastegate to open quickly, and result in more lag. However, if the hole is too big, the wastegate will not open quickly enough, and you will get mega boost spike. If you are running a lot of boost and are near the limits of your headgasket, you don't want that big spike. Otherwise, the spike won't hurt anything, since it comes low in the rev range, where little fuel is used and little power is made.

In summary: If your boost spike is too big, make the bleed hole smaller.
If your spoolup is slow, and your boost spike is small, make the bleed hole bigger.

And yeah, MBCs *do* leak boost out of that hole, but it's so tiny I guess it doesn't really affect anything.

 

[Bohrn]

ahh, thanx for the info on the location.

as for the bleeder hole in the mbc, from my experience, it had nothing to do with spike. I just lost boost after it opened as the ball bearing would float and flutter, not allowing it to close again. With a bleeder hole it just hits boost pressure and stays there.

As for spike, it has to do with the length of the hoses associated with the controller. With long hoses I get lotsa spike. With med hoses I get a wee bit, and with short ones, I get none.

 

[Newlogics]

Originally posted by Bohrn
ahh, thanx for the info on the location.

as for the bleeder hole in the mbc, from my experience, it had nothing to do with spike. I just lost boost after it opened as the ball bearing would float and flutter, not allowing it to close again. With a bleeder hole it just hits boost pressure and stays there.

As for spike, it has to do with the length of the hoses associated with the controller. With long hoses I get lotsa spike. With med hoses I get a wee bit, and with short ones, I get none.

Everything said here is true, I just want to add one last point.

DO NOT use sylicone lines (especially Kragen and Pep-Boys ones) for any boost applications. They expand like crazy, especially when hot. They also collapse really easy, so don't use them as your BOV line. Short braided lines will vertially elliminate plumbin-induced boost spike. Also, stock vacuum hoses doa good job.