Good point and that is ample vacuum. I just can't help but wonder why the bov on the Chevy 1.4L actuates as if the spring were stiffer just by running a direct line to it from the intake manifold.
Bypassing the the bypass valve solenoid.
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Good point and that is ample vacuum. I just can't help but wonder why the bov on the Chevy 1.4L actuates as if the spring were stiffer just by running a direct line to it from the intake manifold.
Hooking directly to the bpv allows the boost/vacuum from the intake manifold to directly control the bpv instead of using the solenoid as a proxy.
I think a lot of the better feel can be attributed to the change in bypass timing with changes in throttle. In normal operation, the bpv solenoid opens in response to releasing the accelerator, at or just before the drive by wire system closes the throttle.
I think a lot of the better feel can be attributed to the change in bypass timing with changes in throttle. In normal operation, the bpv solenoid opens in response to releasing the accelerator, at or just before the drive by wire system closes the throttle.
The procedure you're describing sounds right, but it doesn't follow your results.
The BOV should still open and close like it should. There is a more pronounced "bark" or "chirp" depending on how you release the throttle, but the boost being laggy and the "stiffer spring" description point to the BPV not receiving vac/boost signal like it should. If the BPV doesn't get boost, it is easily blown open. This causes the lag and soft performance you speak of. Not getting vac signal cause it to flutter when letting off.
The 36 pages of reviews of this mod are a 180 from what you describe. There has to be something connected wrong in order for that to happen.
That being said, If you like it hooked back up to the solenoid better, then by all means keep it that way. Not all the cool kids are doing it anyway..
AndrewGS
Ultimo Hombre
So let me get this straight...
This mod will also get rid of the oil in the intake? You don't need a catch can if you perform the Triple Bypass, as firstorbit84 coined it?
On Turbo I was blowing a little oil out of my Forge BOV and got a puff of smoke when shifting out of boost a few times and I was convinced that I should put a catch can on the next car to prevent this.
acamacho104
Member
The catch can is a colassal pain in the rear. I do not recommend. It caused so much **** for me. The blow by is likely due to another issue. I have the same problem. What is the oil consumption like? It could be the piston problem
No it doesn't, but The oil in the charger pipes seems to be coming from turbo. The subsequent overspeeding of the turbo from the BPV not staying seated is somehow causing oil to get past the compressor seal in the turbo. Oil gets into the compressor cover, and then gets sprayed into the charge pipes under boost. After doing this mod, I no longer had any oil in the charge pipes or intercooler for the rest of the time I had the stock set up on the car.
I respect you and your opinions but I'm not convinced. I don't have anything really to disprove your theory but I have doubts that there's that much of a pressure differential (across that seal) decrease caused by this mod to stop oil coming into the compressor housing. And the turbo has probably been spinning too fast since you tuned it the first time, anyway.
It's one anecdotal data point, IMO.Maybe it helps in some other way for blowby but I just don't see it. Who knows, though.
carsNskis
New member
I'm going to submit some completely useless words too.... not because they add any validity the conversation, just because I enjoy the fontI respect you and your opinions but I'm not convinced. I don't have anything really to disprove your theory but I have doubts that there's that much of a pressure differential (across that seal) decrease caused by this mod to stop oil coming into the compressor housing. And the turbo has probably been spinning too fast since you tuned it the first time, anyway.
Maybe it helps in some other way for blowby but I just don't see it. Who knows, though.
Would you believe that of you disconnect the charge piping from the turbo, and drive it that way for a few miles (waste gate fully open to keep the turbo from spinning into orbit), you will have oil dripping out of the comp cover after, for that very reason. Have first hand experience with this. Former employee was modifying his turbo kit for his Miata, and at some point had to drive it home sans charge piping. When he returned the next day and opened the hood, there was oil leaking from the comp cover. Long story short, it was in fact the differential pressure between chra and the back of the compressor wheel causing it. Installed charge pipe, and problem stopped.I respect you and your opinions but I'm not convinced. I don't have anything really to disprove your theory but I have doubts that there's that much of a pressure differential (across that seal) decrease caused by this mod to stop oil coming into the compressor housing. And the turbo has probably been spinning too fast since you tuned it the first time, anyway.
Maybe it helps in some other way for blowby but I just don't see it. Who knows, though.
Thanks for sharing. I'm not sure if it made the difference or the gas did but its a much different beast.
I stopped to fill up with Shell 91, and put a bottle of octane booster in. When I hit the highway, I could easily do 130kph in 6th!
Then later noticed I didn't have to down shift on cruise, 6th would hold most the way and boost stayed higher.
To top it off, I saw a MPG increase too. 100km trip and I got incredible mpg.
Just picked up the car a few weeks ago, and this was the first mod. How can I tell if its been modded or tuned already?
I stopped to fill up with Shell 91, and put a bottle of octane booster in. When I hit the highway, I could easily do 130kph in 6th!
Then later noticed I didn't have to down shift on cruise, 6th would hold most the way and boost stayed higher.
To top it off, I saw a MPG increase too. 100km trip and I got incredible mpg.
Just picked up the car a few weeks ago, and this was the first mod. How can I tell if its been modded or tuned already?
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Boy-Dirt-Car
Member
Just so I've got this straight before I attempt this.... Basically you're by-passing the solenoid and going straight from the manifold to the BOV... correct?
It appears the hose from the bottom of the manifold goes to the solenoid and is very short, like 5 inches. Then there's a hose from the solenoid that goes to the BOV. Have I got that correct? If that's true, couldn't you just put the splice between the two hoses that connect to the solenoid (or a "T" for a boost gauge)?
It appears the hose from the bottom of the manifold goes to the solenoid and is very short, like 5 inches. Then there's a hose from the solenoid that goes to the BOV. Have I got that correct? If that's true, couldn't you just put the splice between the two hoses that connect to the solenoid (or a "T" for a boost gauge)?
Yes you block both ports on the solenoid and run the vacuum line from the RBOV to the intake port.
From what I understand From the cruze guys, that port has a one way valve for generating only vacuum. Therefore a boost gauge wouldn't work. Another port that's direct, like for evap or EGR Solenoid should work.
I haven't tested the feed line to the solenoid to see if it builds boost or not. Sounds like a fancy manifold if that's true.
I think the big difference with this mod is that it stops the computer from bleeding boost when driving. This is most noticeable down low in the first two gears. W/o mod you chirp and go. W mod you burn rubber through first and most of second before it'll hook up. Both times this is with the track and stability off.
On the other hand you can still drive nice and smooth with the mod if you're gentle with the gas. It just responds a lot quicker to input.
From what I understand From the cruze guys, that port has a one way valve for generating only vacuum. Therefore a boost gauge wouldn't work. Another port that's direct, like for evap or EGR Solenoid should work.
I haven't tested the feed line to the solenoid to see if it builds boost or not. Sounds like a fancy manifold if that's true.
I think the big difference with this mod is that it stops the computer from bleeding boost when driving. This is most noticeable down low in the first two gears. W/o mod you chirp and go. W mod you burn rubber through first and most of second before it'll hook up. Both times this is with the track and stability off.
On the other hand you can still drive nice and smooth with the mod if you're gentle with the gas. It just responds a lot quicker to input.
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