Micaiahfied

I was looking at the twins piping at source automotive and saw the cold pipes with the BOV bungs in them, and the BOVs said it may take 2 or more to keep boost to 50psi yadda yadda yadaa.... my question is, is this a safe way to control boost? would it be more likely to overspeed the turbo doing this? any info would be much appreciated i'm just looking to learn and thought this was interesting since i haven't heard much about the use of BOVs on dodge trucks.

edwinsmith

A BOV or Blow Off Valve is used in a gasser to prevent high pressure air from surging back through the compressor wheel when the throttle butterfly is abruptly closed. Since the CTD doesn't have a throttle butterfly a BOV is unnecessary and would produce other unwanted effects such as overspeeding of the turbo if a wastegate were not employed.

The wastegate is also beneficial since it raises the choke point of the turbo while regulating the maximum boost.

A BOV might be used to prevent the whoosh noise heard when the fuel is cut off after a period of high power and boost. The compressed air in the manifold rushes back through the compressor when the heat in the exhaust collapses and reduces the spin of the turbo. Whether this is actually harmful however is controversial. Some say it is and some say it ain't.

Edwin

kjewer1

Back in the old days when turbo technology was a little less robust people ran pop off valves to prevent over boost situations, but they are different from BOVs. BOVs don't lend themselves well to any type of boost regulation at all... They're on the wrong side of the turbo.

I can't see a good way to implement a BOV on these motors to serve any purpose though, since with no throttle plate, you get no appreciable vacuum when you lift the throttle to pull the BOV open. If you rely solely on the pressure spike in the charge pipe to pop the valve, you'll be assing around with springs all day trying to get it to work right, and then as you change boost levels and turbos and such the spring requirement will be changing as well. Plus BOVs are just one more thing to leak boost on you. I only run them on the car because I have no choice.