Weak BOV

[Ibetchuwontdoit]

Tried posting this in the turbo tech forums but it wouldn't let me...

This GST is the 2nd turbo'd mitsu I've owned, and I never had this problem with my previous mitsu. I'm even using the same type BOV on both setups.

Turbo XS RFL

Does just fine when either accellerating normally or pedal to the floor.

If i'm half pedal down it blows off pre-maturely and causes the engine to jerk badly. How can I fix this?

 

[juanpac0]

It's not blowing off prematurely, what you're getting is compressor surge. It's when you set the BOV too tight and the BOV doesn't respond quickly enough/at all to lower pressure/vacuum and the air bounces around in your IC piping. Try setting your BOV softer if you have an adjuster on the top, or try a different spring if that's how you'd go about doing it.

 

[Ibetchuwontdoit]

Will try it today. Thanks, I'll post back with results.

 

[Cassera]

If you can't adjust it, you can always check to see if you have 2 springs..if you do than try removing the smaller one.

 

[LiquidX]

You also need to recirculate your BOV unless you have a GM-MAF+translator or running speed density.

 

[Ibetchuwontdoit]

If you can't adjust it, you can always check to see if you have 2 springs..if you do than try removing the smaller one.

If it's anything like my previous Turbo XS RFL BOV there should be a spring inside. Tho, with my other one I had to add washers to make it compress more because the spring wore out over time. Have not had a chance to look at it just yet, but it was bought this way so no telling who installed it or what they did to it.

You also need to recirculate your BOV unless you have a GM-MAF+translator or running speed density.

I believe it does recirculate...unless the small hose coming outta the top of it does something else. I can't say for 100%, but I'm thinking thats what it's for.

 

[LiquidX]

The small vacuum hose on the top is to actuate the diaphragm by giving positive or negative pressure. Recirculating means you connect the outlet of the BOV (where the air exits) and plumb it into the intake pipe (pre turbo) per stock setup.

 

[BLINKY619]

ok to the op... not to steal your thread... but if someone wants to run their bov to the atmosphere they need a gm maf and translator? i mean cause i like the wooosh sound but it wont idle right if its not recirculated and how much will all that cost? sorry for using someone else thread

 

[DSMDriver69]

ok to the op... not to steal your thread... but if someone wants to run their bov to the atmosphere they need a gm maf and translator? i mean cause i like the wooosh sound but it wont idle right if its not recirculated and how much will all that cost? sorry for using someone else thread

yes you need a gm maft to properly vent to the atmosphere or like said above you could run speed density. Search maf translator and/or speed density.