IS250 S/C installed
Thread Starter
Driver
Joined: Oct 2007
Posts: 191
Likes: 1
From: Greece
The bov didn't work well and that's why the system kept so much pressure.
I changed the feeding of vac/boost to bov
I opened a new thread in the manifold and i removed the small spring from inside.
Taking vac/boost from the already existing fitting on the manifold prooved to be wrong.
Now the synapse stays closed at idle and boost goes up to 5,2 psi.
Flutter is history now.
I lost a lot of power though so i have to dyno the car again to see what's going on.
I need your help on something.
Until 4600 rpm i see only 2-2,3 psi of boost.
5 psi come only at 6500 and only if i have 100 miles and above.
Does yours work the same way?
I finally managed to work the kit correctly.
The bov didn't work well and that's why the system kept so much pressure.
I changed the feeding of vac/boost to bov
I opened a new thread in the manifold and i removed the small spring from inside.
Taking vac/boost from the already existing fitting on the manifold prooved to be wrong.
Now the synapse stays closed at idle and boost goes up to 5,2 psi.
Flutter is history now.
I lost a lot of power though so i have to dyno the car again to see what's going on.
I need your help on something.
Until 4600 rpm i see only 2-2,3 psi of boost.
5 psi come only at 6500 and only if i have 100 miles and above.
Does yours work the same way?
The bov didn't work well and that's why the system kept so much pressure.
I changed the feeding of vac/boost to bov
I opened a new thread in the manifold and i removed the small spring from inside.
Taking vac/boost from the already existing fitting on the manifold prooved to be wrong.
Now the synapse stays closed at idle and boost goes up to 5,2 psi.
Flutter is history now.
I lost a lot of power though so i have to dyno the car again to see what's going on.
I need your help on something.
Until 4600 rpm i see only 2-2,3 psi of boost.
5 psi come only at 6500 and only if i have 100 miles and above.
Does yours work the same way?
Thread Starter
Driver
Joined: Oct 2007
Posts: 191
Likes: 1
From: Greece
Figure stays the same.
The bov has to remain open at idle and light throttle.
Previous setup ws not correct finally because it didn't open even when i steped off the pedal.
So i'm still running 7.1 psi.
I need to find something to richen the AFR and Timing.
I'm thinking of installing an MFU on the return fuel line and bigger fuel pump in the gas tank along with a Camcon, Dastek or AEM F/IC.
Anyway something that will bypass the stock ECU on AFR and Timing for good.
I don't want to install a larger pulley because the car now has a lot of power and i don't want to lose this.
As i see until now i have no problem at all up to 5500 rpm running the car like this.
The problem is from there up to redline.
That's where the mixture gets lean (12.5-13)
I'm now searching for the piggy that will work along.
As far from my research Camcon can do the job on AFR but not on timing.
Any ideas on that?
The bov has to remain open at idle and light throttle.
Previous setup ws not correct finally because it didn't open even when i steped off the pedal.
So i'm still running 7.1 psi.
I need to find something to richen the AFR and Timing.
I'm thinking of installing an MFU on the return fuel line and bigger fuel pump in the gas tank along with a Camcon, Dastek or AEM F/IC.
Anyway something that will bypass the stock ECU on AFR and Timing for good.
I don't want to install a larger pulley because the car now has a lot of power and i don't want to lose this.
As i see until now i have no problem at all up to 5500 rpm running the car like this.
The problem is from there up to redline.
That's where the mixture gets lean (12.5-13)
I'm now searching for the piggy that will work along.
As far from my research Camcon can do the job on AFR but not on timing.
Any ideas on that?
Thread Starter
Driver
Joined: Oct 2007
Posts: 191
Likes: 1
From: Greece
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Thread Starter
Driver
Joined: Oct 2007
Posts: 191
Likes: 1
From: Greece
I got a P0031 bank 1.
Most probably i burned my A/f sensor because of high temp exhaust gas cause i'm running lean.
I need to find a way to richen the A/F.
Andy from Elite said that he will help me to richen the A/F with the AEM FIC that he specially moded for the ISF.
He said that he 'll try to do the same for IS250.
Waiting to hear from him.
Here is a picture of the Vacuum for the Synapse.
I also removed from the inside of BOV the small preload spring and attached to Vacuum source both ports A & B.
Now the BOV works like a charm.
Stays open at idle and light throttle closes when it senses boost and opens again when i step off without fluttering or surge.
Taking VAC/Boost from the already existing port that the manifold has didn't work well.
Perhaps it's not free and it restricts the signal somehow.
I'm only using that right now to feed the PLX Boost and AFR device.
Last edited by pepos; Oct 13, 2010 at 02:25 AM.
Advanced
Joined: Mar 2008
Posts: 613
Likes: 0
From: Illinois
Pepos - Just curious about your comments about the BOV. What do you exactly mean by "open at idle" etc???
All air that goes into the motor must flow past the mass airflow (MAF) sensor. Otherwise the ECU will get the wrong inputs and not adjust the engine parameters correctly. From your description, you might be making a vaccum leak depending on where the BOV is located. Maybe not?
All air that goes into the motor must flow past the mass airflow (MAF) sensor. Otherwise the ECU will get the wrong inputs and not adjust the engine parameters correctly. From your description, you might be making a vaccum leak depending on where the BOV is located. Maybe not?
Last edited by Gaugster; Oct 13, 2010 at 07:07 AM.
Thread Starter
Driver
Joined: Oct 2007
Posts: 191
Likes: 1
From: Greece
Pepos - Just curious about your comments about the BOV. What do you exactly mean by "open at idle" etc???
All air that goes into the motor must flow past the mass airflow (MAF) sensor. Otherwise the ECU will get the wrong inputs and not adjust the engine parameters correctly. From your description, you might be making a vaccum leak depending on where the BOV is located. Maybe not?
All air that goes into the motor must flow past the mass airflow (MAF) sensor. Otherwise the ECU will get the wrong inputs and not adjust the engine parameters correctly. From your description, you might be making a vaccum leak depending on where the BOV is located. Maybe not?
So MAF doesn't measures the air leaking from BOV.
http://en.wikipedia.org/wiki/Blowoff_valve
http://synapseengineering.com/smf/index.php?topic=932.0
So there is no need to recirculate the leaking air to the intake.
When at idle or light throttle the manifold after the throttle body is in Vacuum and when you step on the pedal and throttle body buterfly opens produces boost, when you step off goes to vacuum state again.
So BOV is designed to remain open when it senses vacuum and closes when it senses boost.
Also this BOV works faster than a pushtype one.
http://synapseengineering.com/smf/index.php?topic=303.0
The benefits of this kind of operation can be seen here:
http://www.youtube.com/watch?v=gvnBD...eature=related
http://www.youtube.com/watch?v=M2--IIMSa9A&NR=1
Last edited by pepos; Oct 13, 2010 at 11:14 AM.
Thread Starter
Driver
Joined: Oct 2007
Posts: 191
Likes: 1
From: Greece
That's what i'm trying to do.
Last edited by pepos; Oct 16, 2010 at 01:21 PM.