If the pressure rise in the intake tract is worse than in the UIM....

IE - if closing the throttle or going half-throttle causes the turbo to spike.

 

/\ if you do this you will have to disconnect your synchronic wont you ? I think that valve would vent excess pressure under part throttle - from what I could make out .

 

Yeah it will.

But that is the point right - get the right BOV for your set-up is better than jacking with your BC.

 

yes - I agree with you on that point
will you put away the soldering iron now ?

 

I'll do both just to satisfy curiosity.

And I'll unplug the iron; but I'll go ahead and keep it out.... LOLZ

 

So, let me make sure I read that link on on the Synchronic correctly; you must recirc the thing because it doesn't close when in vac or run the risk of it sucking in unmetered/ unfiltered air while in vac.

 

Yep.

If your tuning with a MAP based system you can just put a small filter on it and run it VTA... but a MAF one needs to be recirculated.

 

****... what about that anti-stall fitting I've been hearing about? Given the placement of the BOV on the SFR kit I'm not sure it can be recirculated....

 

I didn't find that the anti stall fitting worked so well. In theory I don't find fault with it, but in practice it didn't make the car drive as well as when it was recirculated.

 

Crap....

 

Bit of an update on this .
I decided that I wanted to go back to plumbing my BC off the UIM because I got sick of the "overboost" light and beeper going off on my Greddy profec BC .
So - i put it back . Straight away I saw some serious pressures before the throttle plate at partial throttle . NOT GOOD !
After reading the Syncrhonic BOV information I decided I should try and rectify this with the BOV i already have seeing as how i'm short on $ ATM .
With these two measures I have been able to cut down my max. boost behind the throttle to below 15psi under all conditions.

1/ Significantly reduced the spring tension on my BOV such that it almost opens at idle .
2/ Adjusted the "SET GAIN" (IE controller on start pressure) value on the BC down to around 4psi . Any higher than this and you will have a problem because the UIM does not see nearly as much pressure as before the throttle under partial throttle and as your BC wont start operating your wastegate will be completely shut .

 

Don't have the synchronic - would like to get it someday though , as I can see some real benefits .

Just trying to tune what I already have to get a similar result .
BTW - MAF based tune with recircd BOV

 

Ever do this ?
I'm still thinking BC should not be plugged into UIM unless you have a BOV capable of venting any excess pressure .....

 

Nope not yet man sorry - I have been crazy busy trying to wrap everything up before I go to Florida for Dive School.

 

Kane - you never tested this you slacker .
I'm still saying plugging your BC in before the throttle plate is a superior setup to after .
I get less boost at part throttle and better throttle control .

I briefly flirted with putting it back after the throttle plate but my throttle control went to **** so reverted back .

 

I haven't even seen my car in 4 months...

Just cause you like it - doesn't make it right; unless your turbine is too small...

 

^of course the turbine is to small..lol.
I thought that was a given.

 

Just cause "everyone does it that way" doesn't make it right either

 

But "cause that is how it is designed to work; and it works perfectly well" - DOES make it right.

 

I doubt any of the serious people that are participating in this thread EVER do something because everybody else is doing it.
You can probably count on us to intentionally do it every other possible way for that very reason.

Plumbing the boost controller signal before the throttle is dumb on many, many levels.

 

Not on my car it doesn't .
And I would bet you a case of beer that other Greddy owners have similar issues. Although many would not even know they had an issue because they just accepted that that is how it is .

 

Give me something a bit better than that please - like an explanation .

 

What kills me is that you are making the turbo less effective; we WANT a turbo to be producing the highest boost at all times without slowing down (outside of the Surge Range).

That is one of the reasons we have BOV's and boost controllers.... to allow the turbo to spin happily away while we tap into that extra airflow when we want it with the throttle.

By purposely fooling the BC by giving it a higher boost level than what is in the intake manifold your forcing the wastegate closed slowing the spool instead of just venting the air out of the intake tract - if you are having issue controlling boost threshold - fix your turbo, bov etc....

 

Not less effective at all - just more controllable .
If I set "start boost" at say 8psi and set boost at say 10psi then i'll actually get 8 - 10 psi before the throttle plate (in all load situations)with my setup . If I plug into the UIM i'll get whatever the f**k the turbo wants to spool to (at partial throttle)- I saw up to 20psi before I got my BOV sorted .
Now imagine you are half way around a corner and you have 20psi before the throttle plate and you dial in more throttle . Guess what is going to happen .... BTW I have actually experienced this and as far as I can tell you (nor MM) have not so maybe I might have a clue - maybe .

I would agree that you can control any excess boost with your BOV and thus prevent the above scenario but only a few top of the line BOVs will do this . Most BOVs are not going to control it and the result at best is a very touchy throttle and at worst a very nasty accident .

 

hmm..so how would I setup my BC with my Synapse WG ? With this one it makes use of the same port even with a BC. They dont recommend using a secondary port ont he WG to hook up a BC.
http://synapseengineering.com/smf/in...54&topic=434.0
So would I want to use my signal right after the turbine..or the UIM signal ?