Boost sag? No, you don't need EBC.
#61
I was thinking that even guys w/EBC's will see more consistent boost w/the signal coming from B. So, I thought I would try it. On my set-up the WG rpm needed to be dropped a bit, but yup, boost doesn't droop nearly as bad as it did with the signal coming from A (not that it drooped much, about .5 lb. @ 7000 rpm with the EBC setting at 12 lbs). Now it's only .1 lb. I had to drop WG rpm because of boost overshoot .
So for those guys with an EBC like mine, using Joe's suggestion will also allow for more stable boost control with your EBC.
So for those guys with an EBC like mine, using Joe's suggestion will also allow for more stable boost control with your EBC.
#62
The explanation for where to put the wastegate sense line is brilliant! kudos!
#64
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How much of an increase do peiople usually see? I don't really want to jack with a boost controller, but 1 or 2 psi will be a safe increase...3psi means I'll make too much power/torque for my lil trans.
#65
I am using a manual boost controller and can't hold peak psi - it drops like a rock, but not linearly - see attached 13.5psi peak line. I am going to try tapping the cold side piping as you suggest. Would the sharp drop and then slow taper after peak (shown in attached) be indicative of being solved by tapping the cold side, or is something else causing the problem - like too restrictive of a cat causing a weak actuator to blow open or similar?
#68
If you're using a TB type single point fuel injection and the PO valve is installed after the TB, you're venting potentialy explosive fuel vapors directly into your engine compartment....not a good thing. The dump valve is supposed to loudly go poppoppop, not boom.
#69
Yes, the placement of the valve is before the TB, but the FEED line telling the valve to open..?
I might have misunderstood something very basic here, but isn't the feed line sensing the pressure difference on the other side of the TB, and then telling the valve to open because the TB has been closed..?
I might have misunderstood something very basic here, but isn't the feed line sensing the pressure difference on the other side of the TB, and then telling the valve to open because the TB has been closed..?
#71
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Yes, the placement of the valve is before the TB, but the FEED line telling the valve to open..?
I might have misunderstood something very basic here, but isn't the feed line sensing the pressure difference on the other side of the TB, and then telling the valve to open because the TB has been closed..?
I might have misunderstood something very basic here, but isn't the feed line sensing the pressure difference on the other side of the TB, and then telling the valve to open because the TB has been closed..?
#72
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As stated elsewhere in this thread, you should take your wastegate/MBC signal from the coldside before the throttle body but after the intercooler to help prevent spiking. It is difficult to diagnose a possible additional problem with your MBC until you make that change.
#74
As stated elsewhere in this thread, you should take your wastegate/MBC signal from the coldside before the throttle body but after the intercooler to help prevent spiking. It is difficult to diagnose a possible additional problem with your MBC until you make that change.
The only reason I asked about spike vs taper before tapping the cold side is because my boost curve seems to be so visually different than a taper (drops like a rock before it tapers, lol). I can live with a little taper, but the quick drop from 13.5 to 10psi is the killer. I just did not want to pull the cold side pipe and tap... if this spike was atypical from simply an intercooler pressure drop.
#79
Yes, the placement of the valve is before the TB, but the FEED line telling the valve to open..?
I might have misunderstood something very basic here, but isn't the feed line sensing the pressure difference on the other side of the TB, and then telling the valve to open because the TB has been closed..?
I might have misunderstood something very basic here, but isn't the feed line sensing the pressure difference on the other side of the TB, and then telling the valve to open because the TB has been closed..?
#80
I have the GReddy td04 15g turbo, and it has a connection at the housing for the wastegate. This is ofc in the wrong end, but I still used it at first since I wanted minimum boost when I started mapping.
Today, when I connected my boost controller, I moved the line up to the connection at the 4th runner on the intake manifold.
And my GOD was there a difference..
My car went from getting .25 bar to .4 bar, and that bitch got EVIL.
Massive difference on a GReddy turbo with intercooler. Just massive.
Today, when I connected my boost controller, I moved the line up to the connection at the 4th runner on the intake manifold.
And my GOD was there a difference..
My car went from getting .25 bar to .4 bar, and that bitch got EVIL.
Massive difference on a GReddy turbo with intercooler. Just massive.