I got into a debate with a couple buddies of mine about how to best run the vacuum lines for my Tial 35mm WG.

They recommended I run the vacuum line from the wastegate to the nipple on the compressor - that's how it's setup now. But I thought that the best way to run it is to cap the nipple on the compressor, and run a line from the WG to a vacuum source such as the FPR line.

Which way is better for spool and response? I am running a 7 psi spring on the WG, but it's only seeing about 6 psi at the gauge.

Another question about my Greddy BOV. I'm running the upper nipple to my brake booster, and the lower nipple is left open. Should I run a line from the lower nipple to a vacuum source, or should I run a line to the compressor nipple? I was told that it should be run that way for best response.

I ask this, because I was running this BOV on my Greddy kit, and it blew off loud as hell. And now with my SC50 at the same boost level, it doesn't blow off the same at all, it's quiet and whistly - not whip-like, how it was before.

Tips on how to get the best response out of my WG and BOV?

 

Anyone?

 

You want the lower port of the BOV to be hooked up to pre-throttle body boost pressure. If you adjust the sensitivity of it, it will also change the sound of it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Das Schmoo &raquo;</TD></TR><TR><TD CLASS="quote">You want the lower port of the BOV to be hooked up to pre-throttle body boost pressure. If you adjust the sensitivity of it, it will also change the sound of it.</TD></TR></TABLE>

Pre-throttle body = charge pipe?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostincoupe &raquo;</TD></TR><TR><TD CLASS="quote">

Pre-throttle body = charge pipe?</TD></TR></TABLE>

Any piping between turbo compressor outlet and throttle body. I have my flange tapped for that pressure.

 

I have the Greddy Type S bov as well, and i left the bottom nipple open. Is there any particular reason i should route it back to a vacuum source? Are there any detrimental effects if i leave it the way it is?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Das Schmoo &raquo;</TD></TR><TR><TD CLASS="quote">

Any piping between turbo compressor outlet and throttle body. I have my flange tapped for that pressure.
</TD></TR></TABLE>

Did you really know any difference in sound and the way it opens? Before and after you did this?

 

Yeah can some one do a diagrahm about this cause I am kidn of confused right now. I thought both nipples went to the same vac source.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drintegra &raquo;</TD></TR><TR><TD CLASS="quote">Yeah can some one do a diagrahm about this cause I am kidn of confused right now. I thought both nipples went to the same vac source. </TD></TR></TABLE>


Get a vacuum manifold. Hook it up before the check valve on the booster line.
Then run an individual vacuum line to the BOV and the wastegate.

I think the idea of routing the bov line right before the TB is a good idea - i guess it offers a little more security. If you want a boost controller - just tap that in between the wastegate and the vacuum source.

Look at these two links.

https://honda-tech.com/zerothread?id=1263795

https://honda-tech.com/zerothread?id=635014

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Outkast95LS &raquo;</TD></TR><TR><TD CLASS="quote">I have the Greddy Type S bov as well, and i left the bottom nipple open. Is there any particular reason i should route it back to a vacuum source? Are there any detrimental effects if i leave it the way it is? </TD></TR></TABLE>

Same here. I'm thinking about tapping my charge pipe to utilize the boost assist feature. Any difference in the way it sounds before / after?

 

bump for tips on how to run my WG line. Should I run it to the compressor nipple (as it is), or cap the compressor nipple and run the WG to a vacuum source?

 

I have mine reverenced after the throttle body because my turbo doesn't have a compressor nipple. Have had no issues.

I've *heard* that when it's referenced off the compressor housing you won't get your full boost because of the pressure drop of the intercooler. However, when it is referenced off the compressor housing, you get the quickest response and consistency.

 

Correct me if I'm wrong, but I've heard that getting your vacuum source off of the compressor housing for either wg's or bov's leads to slower and less responsive work.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by awdgsx96 &raquo;</TD></TR><TR><TD CLASS="quote">Correct me if I'm wrong, but I've heard that getting your vacuum source off of the compressor housing for either wg's or bov's leads to slower and less responsive work.</TD></TR></TABLE>

Referencing off the compressor is for a wastegate only because it operates on positive pressure. It is not a vacuum source. Only a boost source. A BOV would not work.

It's good because you have a short line from pressure to the wastegate so you get quicker response.

 

Oh ok, I see what you mean, sorry for the misunderstanding.

 

No problem at all.

 

As for the Greddy BOV thing...I just tapped a 1/8NPT plug into my charge pipe, made the BOV louder and faster opening response, sounds wicked.

 

i drilled my charge pipe right after the turbo and put a fitting on there w/ some JB weld. BOV sounded really loud and very quick as far as response.

the jb weld cracked and i had a boost leak from there so i took out the fitting and welded a piece of pipe to cover it up. now i have the bottom nipple of the type s open and you can definately tellt he diff before and after.

now it has a bit of lag before it blows off, and its no where near as loud as before.

im going to try and tap it right under the bov flange like shown above, im just worried there might not be enough metal to actually tap and have it seal correctly.

 

hmm...i don't have a 2nd port on my greddy RS.....

but anyways. best sourse for the wg would be the compressor housing. i have my hooked up to my vac manifold (which is t'd off from the brake booster)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Buzzbomb &raquo;</TD></TR><TR><TD CLASS="quote">I have mine reverenced after the throttle body because my turbo doesn't have a compressor nipple. Have had no issues.

I've *heard* that when it's referenced off the compressor housing you won't get your full boost because of the pressure drop of the intercooler.</TD></TR></TABLE>

true talk

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Das Schmoo &raquo;</TD></TR><TR><TD CLASS="quote"></TD></TR></TABLE>

Alright, just an update for those watching this thread. This weekend I hooked up my BOV like the above picture.

The difference was surprising to say the least. The BOV seems to react quicker and smoother. The sound changed too. It now makes more of a higher pictched whoosh. I like it better.

 

Best method is to drill the holes in the rear lower of ur intake manifold for each accerie IE one WG and 1 BOV and then tap them and put a fitting in there. By doing this my bov stop shuttering and the wg opened faster.

josh