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HKS SSQV 4 for Ranger raptor
- Thread starter 25rr marsh grey
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Unit 91
Well-Known Member
Technically it's a bypass valve.
The stock system puts air back into the system behind the MAF I'd reckon (most stock turbo systems are like this), which means the computer is calculating for that air that isn't actually passing the MAF. So, when you remove that air you can run rich temporarily. It's probably not detrimental, but there is always a chance it won't run as well, and possibly trigger a CEL.
Here is some more info from some Subaru dork -
RB205
Well-Known Member
I'm an ex Subaru dork and I'm pretty sure these engines run MAP and speed density. Similar concepts still apply and BOVs are always a waste of money until you're running a big turbo and external wastegate.
Unit 91
Well-Known Member
You're probably right on the MAP sensor. Would make sense. I did not do more than cursory (poor) 'research.'
Basic concepts still apply with regards to what the ECU assumes.
Raptor Family
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One of the key reasons stock vehicles use diverter valves instead of blow-off valves is because of emissions. On our trucks, the diverter valve is attached to the outlet pipe of the drivers side turbo (hot pressurized air side). When the valve opens, it diverts that hot, high pressure air to the crossover pipe that feeds the inlet of that same turbo. That inlet has a plastic elbow with the PCV hose fitting on it. All the vaporized oil and unburned hydrocarbons are sucked through the PCV valve on the valve cover and are piped into that turbo when it is at boost. With a diverter valve, when it opens, the oil mist and hydrocarbons are contained in the crossover pipe and recycled back to the turbo to be re-burned. With a true blow-off valve, all that vaporized oil, unburned hydrocarbons, etc., are dumped straight into the environment.
For everybody that has wondered about, or considered a catch-can, this is that oil that it would normally catch. While under boost, the vaporized oil and unburned hydrocarbons are at their highest concentrations—then the blow-off valve dumps this hot charged contaminated air straight into to the environment.
For everybody that has wondered about, or considered a catch-can, this is that oil that it would normally catch. While under boost, the vaporized oil and unburned hydrocarbons are at their highest concentrations—then the blow-off valve dumps this hot charged contaminated air straight into to the environment.
