MBC Tuning Help!

[pitbullowner_2]

i just bought a mbc and when it got to my house through the mail the knob got loosen so i'm hesitant when tuning because i dont know if it will hurt anything being to low.. also the company told me that the mbc's are real touchy when tuning has anyone ever had problems tuning it.. also should i set it at 10 psi for right know or what, i have everything stock now and it is at 14psi

 

[ChvyKc]

i just bought a mbc and when it got to my house through the mail the knob got loosen so i'm hesitant when tuning because i dont know if it will hurt anything being to low.. also the company told me that the mbc's are real touchy when tuning has anyone ever had problems tuning it.. also should i set it at 10 psi for right know or what, i have everything stock now and it is at 14psi

What kind of boost controller is it?

MBC's are funny. I have a Hallman and when I am adjusting boost between 12 and 19 pounds it is really touchy meaning that a quarter of a turn is about a pound. When I get above 20 pounds though it takes about two turns to get it to go up another pound. So the way that the mbc controls boost is not always consistant according to how many turns of the knob that you make.

 

[dsm-onster]

i just bought a mbc and when it got to my house through the mail the knob got loosen so i'm hesitant when tuning because i dont know if it will hurt anything being to low.. also the company told me that the mbc's are real touchy when tuning has anyone ever had problems tuning it..

Screw it all the way in and turin it up one turn at a time. I've made my own from homedepot parts and had to start this way as it obviously didn't come preset. Don't be skurd. Just do it!

also should i set it at 10 psi for right know or what, i have everything stock now and it is at 14psi

Based on what? do you have an aftermarket boost gage? The stock boost gage just calculates theoretical manifold pressure based on airflow.

 

[pitbullowner_2]

i have a voo-doo one i bought off ebay for $20 guaranteed up to 30psi but anyways i should screw it all the way in? i thought that was higher psi and the looser was lower psi...also i have a boost gauge coming in the mail should i wait till i hook it up first then go off that so its more precise?

 

[dsm-onster]

HOLY HE!! you're right back it out as far as you can. I don't know what I was thinking. If you screw it in all the way the spring will offre so much tension that it will never let the wastegate actuator even see boost. I am very sorry to mislead you. Yes, Have it bearly screwed in when you first install it just to be safe... And just like ChvyKc says MBCs are hardly ever linear with respect to the adjustment.

 

[pitbullowner_2]

so should i check it about every 1/2 a turn untill it starts to get close then 1/4 or so, also starting out when i shake it i hear the ball bouncing around should i tighten enough so i cant hear it then start from there

 

[ChvyKc]

HOLY HE!! you're right back it out as far as you can. I don't know what I was thinking. If you screw it in all the way the spring will offre so much tension that it will never let the wastegate actuator even see boost. I am very sorry to mislead you. Yes, Have it bearly screwed in when you first install it just to be safe... And just like ChvyKc says MBCs are hardly ever linear with respect to the adjustment.

I didn't even notice that you said that. You definately want to make sure that you loosen the MBC up all the way then just go from there.

 

[dsm-onster]

so should i check it about every 1/2 a turn untill it starts to get close then 1/4 or so, also starting out when i shake it i hear the ball bouncing around should i tighten enough so i cant hear it then start from there

That's a good plan of attack .

 

[pitbullowner_2]

thanx alot guys i'll try it and let you know how it works out