I just installled a new synapse bov and am having some problems with it fluttering then blowing off. The car is making ~-10psi of vaccum at 850-900 rpm. I'm assuming -10psi is ok since I redid all of my vacuum lines, checked them for leaks, changed the tb gasket and intake manifold gasket and used hylomar gasket dressing. I even put silicone on all of my vacuum connections and was still making -10psi vacuum. Does anyone know if that is ok and why the bov is causing this slight compressor surge?

 

Where are the vacuum lines from the BOV connected too?

 

oh boy..wait till tial and tony get on here

 

u sure its at 10? that's a little low

 

The two in the back are teed together then tee to the map sensor, then connect to the intake manifold. The fitting on the side is not connected to anything.

 

give the map its own dedicated line, tee the bov off of the pcv, or give it its own.

 

fyi, 10 in/hg is a little low. should be 20+-

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .CUBISH. &raquo;</TD></TR><TR><TD CLASS="quote">oh boy..wait till tial and tony get on here </TD></TR></TABLE>
nothing we didn't already know about

 

im guessing this is on a b or d series honda of a sort.

sounds like something is wrong aka vacuum leak, if you are only making 10 inches of vacuum.

 

Mike, do you guys warranty these things? lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Mike, do you guys warranty these things? lol</TD></TR></TABLE>

LOL

 

10 in/hg is pretty low unless you got some lopey cams. 18-22in/hg is more like it. Give the BOV it's own vacuum source as stated above.

 

How big of a hose are you using for the vacuum line?

 

put a diffrent bov and see if it changes

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostfed.com &raquo;</TD></TR><TR><TD CLASS="quote">10 in/hg is pretty low unless you got some lopey cams. 18-22in/hg is more like it. Give the BOV it's own vacuum source as stated above. </TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Mike, do you guys warranty these things? lol</TD></TR></TABLE>
drink was sprayed across my monitors LOL

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostfed.com &raquo;</TD></TR><TR><TD CLASS="quote">10 in/hg is pretty low unless you got some lopey cams. 18-22in/hg is more like it. Give the BOV it's own vacuum source as stated above. </TD></TR></TABLE>

It idles and runs fine with -10 psi so I let it go. I had a blitz bov on there before and it did not surge at all.


My intake manifold has only 3 ports for vacuum and I have 7 devices that need vacuum, so I used 3/8" hose from the 3 ports then teed each one and reduced the hose size to fit the device. Right now the brake booster, pcv, and boost gauge share one, fpr and iacv share one, and the bov and map sensor share one. So should I run the map sensor to the one with the brake booster or the iacv?

 

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

It idles and runs fine with -10 psi so I let it go. I had a blitz bov on there before and it did not surge at all.


My intake manifold has only 3 ports for vacuum and I have 7 devices that need vacuum, so I used 3/8" hose from the 3 ports then teed each one and reduced the hose size to fit the device. Right now the brake booster, pcv, and boost gauge share one, fpr and iacv share one, and the bov and map sensor share one. So should I run the map sensor to the one with the brake booster or the iacv?</TD></TR></TABLE>

Answer the question stock cams? Yes or no.

10 in/hg is LOW not enough for your BOV you need to give it a stronger signal and fix your leaks. What your old BOV is irrelevant.


Modified by MidShipCivic at 10:03 PM 9/12/2007

 

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

Answer the question stock cams? Yes or no.

10 in/hg is LOW not enough for your BOV you need to give it a stronger signal and fix your leaks. What your old BOV is irrelevant.</TD></TR></TABLE>

yeah really......my maz cams arent that bad.

 

Something wrong with 10" vac for sure.

However, you will probably need to set up a boost only line regardless. All you need to do is put a barb fitting in the charge piping with some sealant and then hook it up to the SIDE port on the BOV.

You will also need the vacuum source on the two nipples on the rear of the BOV.



If you don't have vacuum leaks the BOV will work perfect.

 

They are just the stock euro-r cams. Would it leak that bad if it needed a valve lash? They don't suond like their really loose or anything. If it it is only making half the vacuum it should be, should I be looking for something significant?

 

if the valves are tight hell yeah the vac will be way down i tuned a car for a dude i couldnt get it to idle in thelower columns it was in the higher ones. and it was because the valves were hanging open.

 

Is your gauge reading in PSI or inHG? 10psi is ~20inHG, so -10psi is fine. 10inHG is way off.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nowtype &raquo;</TD></TR><TR><TD CLASS="quote">Is your gauge reading in PSI or inHG? 10psi is ~20inHG, so -10psi is fine. 10inHG is way off.</TD></TR></TABLE>

ok that holds at least a little validity, but about 90% of the people on this board say "/hg is psi like 10 psi vacuum.

so for now i will give the benefit of the doubt, BUT i still go with my original statement, the map and the bov need separate vac sources.

 

I would put a bling bling vacum manifold o so you dont have a bunch of tees in there that are potential spots for leaks.Is the Synapse adjustable via spring etc for vacum load?