What I was thinking. I am going to take apart my MBC just for ish and giggles. Also going to
Unload the pre load spring a but and then try again.

 

It will become apparent when you consider the response differences and how well it holds boost. I didn't believe it myself until I was retuned. I have never had any boost holding issues with the Synchronic. I have been through several stock style BOV's including (Tomei, stock crushed and Dejon modded ).

 

The only reason I can see that would explain the need for a retune would be to adjust AFR if the previous BOV was leaking. I went from a Forge to the Synapse and didn't have to change anything in my tune.

 

In your case maybe so...

I have seen several instances where the stock style BOV's acted like they leaked boost. In fact there are posts on this forum that present this. What fuel do you run? What boost are you tuned to? I also noticed you are running a 3-port BCS as am I. Is the OP on a stock BCS? These are all things to consider and can vary the response this BOV has on each application.

Like I said...This BOV is a good one but does not have an identical response for everyone that uses it. Just trying to provide "out of the box" suggestions.

 

91 octane and 24 psi on my street tune, 94 octane and 22 psi on my road racing tune. Stock IX turbo.

OP is on an MBC if I'm not mistaken.

 

Correct 93 oct on hallman mbc

 

I see some here are having similar issues as me, I had a turbo xs(something like that) bov but was recirculated. Got 1250cc injectors, BC cams, MBC, high flow fuel pump, and got it street tuned after installs. I bought the synapse synchronic bov and installed it to VTA, hooked both ports A & B up(no port C on bov) and preload screw all way out, ran like ****, moved it almost all the way in and idled a little better but still skips from 1k to 3k rpms, made real small adjustments to it but still want to stall and skip through the low rpms...I am quite new to this, have a few buddies who help but need more experienced help!! Do I need both ports A & B hooked up? Or can I hook just one port up at a time and try it without hurting anything?..,or is there something else I'm missing? Lol....remember I'm new to all this, so any help would be greatly appreciated!!! Thanks!......also I'm running around 25lbs of boost on stock turbo

 

No you don't need both ports hooked up. You can try just going to port A see if that helps then swap and try just going to B. I got mine to run better but not perffect. I ended up going with the TIAL in the end. I did like the spool beeter with the synapse... Also I swapped my vacum line coming off the IM to the BOV. I did away with the hard pipe and ran one vac line direct to the BOV.. Just another thought. Let me know if you want any other help

 

Ok thanks! I'll try that when get home from work, I was told had to have it retuned also and was hoping that wasn't the case. But will update in couple hours, thanks I appreciate it!

 

Its weird how it works flawless on some sets ups and not on others..

 

Yeah it is weird...another question tho, I still am using the stock MAF sensor and air intake system, would I need to eliminate the MAF sensor, add a new air intake and change to like a speed density setup to VTA? Guess I should of added that part too

 

If I had your set up I would goto SD.. Since you VTA.. probably would run better....

 

Going with the SD, seems to be the better route for me. Hopefully in couple weeks after its done it will run better, just recirculated the bov for now so can actually drive it. Thanks for the help tho I appreciate it!

 

Nice. I think you will be very happy once you go SD. Good luck !!!!

 

Ps you can recirc with sd too.. sd is perfect though.