Mike Holmen

You can do a search on ebay and find a ricer blowoff valve. Its basically a check valve. I would put you blowoff switch on the clutch pedal or the TPS sensor. You just need to dump some of the boost off. Surge is hard on thrust bearings. You get to much end play, the compressor or turbine will be pushed into the housing, then you break the shaft. There are compressor that are day in day out surged, you just have to limit how hard/severe that it occurs. As for the guy lossing the prime, I bet one of you're connector tubes are leaking or a a line on the injection pump is leaking. The bleed off when the pump isn't running. I have a few bad orings on mine but I don't have time to fix. The injector might not even be in tight enough to seal up the copper washer completely.

kennyblatz

my turbo bark is nasty and a bd blow off valve is next on the list. yes it is expensive, the tial valve it uses is only around 200 bucks but since there is no throttle bd had to make the electronics to hook up to the tps and clutch on a standard. it is fully ajustable so you can tune it just right for how much you let out to get bark and just the right spot when engaging the clutch. someone said theres no point cause it lets the air out well yes the air is let out so the turbo can maintain a high speed during the shift allowing for a faster spool up when getting back on the fuel.

TexasHardcore

Turbo Bark for Dummies 101:

Take a small desk fan out to your garage. Turn it on high. Now with a air nozzle on your compressor...spray toward the fan. What you hear is a plastic/slower rpm version of turbo bark. Imagine the same thing going much, much faster, and in a pressurized system.

On your engine, this noise you hear is the air being choked up in the intake manifold because the engine no longer needs that much air when the rpm's drop, thus causing a surge of pressure through the system. When the air is choked up, it has nowhere to go, and the turbo doesn't know the difference.

The surge in air pressure puts ALOT of thrust (in & out) pressure on the turbocharger impeller, bearings, and turbine shaft, which is a big reason you see so many broken shafts on turbochargers.

Take a gander at some YouTube videos on sled pulling trucks, and you'll notice that after they come to a stop after a pull, they'll pump the throttle a few times to slow the turbocharger down. You have to remember that a turbocharger spins in excess of 150,000 rpm, so any backfeed of pressure is going to slow the turbocharger down (never to, or near a complete stop) kind of like how an engine brake works.

Fishin2Deep4U

This guys sounds he just wanted the ricer noise. In that case, the simple micro switch is all that's needed.

For manual trucks, BOVs can actually reduce the spool time between gears as the impeller speed does not slow as drastically as there is no boost slowing the impeller. This means time to start making boost os much faster after the valve closes and exhaust energy is added.

It does work. And it's not just for sound.

The great thing about a BOV in any truck is backing off tailgaters. Simply open at any speed and instant smoke and heat.

Dave

j_k_auto

Yea I would like to make a setup that will make some noise and help my turbo live longer. I do know having one on will save the turbo because of surge and bark. backpressure is no good for the turbo.

I am thinking on getting the loud valve and tuning it the way I need to hooking it up to my tps wire.

Tate

I like the idea of using the pressure differential between the exhaust manifold and the intake to trigger the BOV. If you don't let off the throttle completely to trigger the micro switch, then its no good. You don't have to get completely off the throttle for the turbo to bark.

Mike Holmen

You could also use the differential across from your turbo discharge pressure to the engine inlet. You could rig up a BOV to open at when the pressure at the engine is higher than turbo. Put the BOV just before the air horn. Lots of ways to rig one up. You could also lift the throttle softly prior to shifting. Kinda hurts 60 ft times. I don't use one, as I just baby my truck.

98.5Hotrod

Try Engineered Diesel in MI, they have a BOV set up to operate off of drive pressure and a spring. They are around $200 bucks. They make high quality stuff. Give them a call at Chris 616-608-2977 or Glenn 616-890-1470.

powermad

sorry i couldnt read on any more got bored with it but heres my 2 cents. guys with manual transmissions can benifit from a bov because it keeps the turbo spinning freely with little back pressure while shifting it will help your tubo live longer but most bov for our trucks run over 500 bucks and isnt realy worth it. theres thousands of guys out there with 1000hp and how many of them have bov? external 60mm wastegates yes... but bov no. but if you have the money go for it its not like your truck is going to self destruct by installing something to help keep the turbo spooled between shifts