Why no blowoff valves?
- Thread starter Pony Express
- Start date
No not yet but maybe some day ,I imagine they are top shelf though , I use there waste gates in every kit we do that an external gate is required and they are def the best out there IMOP , I can get "tial" or "precision" gates for quite a bit cheaper but I still use the synchronic's , short of leak problems on there 50mm v-band style i have never had one of there gates fail .
yea, i had leak issues on the v-band flange of my gate but the copper high temp sealant fixed it
Trent, how do you know what type of setup will need a wastegate or bov? I always thought they were for a smaller charger but now I see that they are for a lot of applications..would I benefit from one?
Waste gates and BOV's are almost mandatory on gasser turbo systems since the engine it self can only handle a limmited amount of boost and when you let off the throttle there isa throttle body that closes fully so barking turbo's is easier and more dangerous.
On diesels it is not so simple, there are way to many variables to really go over in 1 post but the short answer on waste gates is it depends on the turbine wheel size , A/R used , and how much fuel / heat your feeding it. If your buying turbo's from people who have ran what there selling it is as simple as asking if its needed and they can go over the details from there testing , if your deciding on something that is already on your truck it really boils down to knowing what your drive pressure is and also knowing the MAP for your turbo and at what Pressure ratio it can be ran to efficiently, after you have that info it is very easy to know whether a waste gate is needed or not , for under 700 hp almost all of the turbo's that are popular do not require waste gates but that doesnt mean that they could run a little more efficient with one. An example is the GT4202 I have on my DD right now has no waste gate , but the turbine is large enough for how much fuel/ heat i am feeding it so it is only seeing about 40 psi of boost and only 42 psi of drive pressure, but if i cranked the truck up with a ton of fuel and spun it to 55-60 psi it would be off of its map and would have to be waste gated .
BOV's the best way to decide is think to yourself how many time a year you bark the turbo doing burn outs , ect and decide if the cost of the BOV is worth the insurance for the turbo or if its cheaper to fix the turbo if it ever fails a s a result.
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The BOV I have is a piston type, that's how I drew it out in my 'diagram'. The check valve i did not put in the diagram as every vehicle is different. The reason I have the check valve in my boost reference line is it keeps the valve open longer, by keeping the boost pressure higher/longer on the boost reference side of the valve. This helps to make sure all the boost is dropped before the spring pressure overcomes the valve and shuts.
My issue I was having before installing the valve was it would still open after drive pressure dropped, however it would shut too quick and would still bark. The check valve keeps the boost pressure signal high in the valve longer resulting in the valve staying open a little bit longer. And so far every BOV I've seen has had two ports on it. Even that synchronic has two ports. I believe the 1 port valves just use boost pressure AT the actual valve to open it once pressure drops on the other side.
If any of that makes sense haha.
My issue I was having before installing the valve was it would still open after drive pressure dropped, however it would shut too quick and would still bark. The check valve keeps the boost pressure signal high in the valve longer resulting in the valve staying open a little bit longer. And so far every BOV I've seen has had two ports on it. Even that synchronic has two ports. I believe the 1 port valves just use boost pressure AT the actual valve to open it once pressure drops on the other side.
If any of that makes sense haha.
The check valve was used due to vehicle/valve/turbo characteristics. Each setup will be different and require different little fine tuning adjustments. This is what works on my truck with this valve. Some of you might not even need to make any adjustments.
Had some time to kill on lunch break today. A before and after vid. The before vid shows it barking slightly. I didn't feel like trying to get it to bark as hard as I could.
Before:
http://youtu.be/U5j6ndhXvb8
After:
http://youtu.be/qWFhno0lfVQ
Before:
http://youtu.be/U5j6ndhXvb8
After:
http://youtu.be/qWFhno0lfVQ
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The video's don't really do justice. Its a lot louder, both the bark and the blow off. Plus when I'm hauling my camper/trailer over the rocky mountains it will do it a lot harder.
Some pics as of today:
You can see where I tapped into the wastegate line for the boost reference. Just so we're clear blow off valves and wastegates are completely different in reference to this thread. I've had a bunch of people ask me why I need a BOV since I already have a wastegate. Also the valve is just tapped into the boost reference for the wastegate, it it has nothing to do with the wastegate operation.
This valve actually has 3 ports coming off of it. The clear(ish) hose use to run into the port that is attached to the black hose from the wastegate boost line. The valve used to get its boost reference from directly at the port opening but as I've said I noticed a lot better valve operation taking the boost reading from the other side of the intercooler. So that is why that one port is blocked off.
The 'drive pressure' port is right underneath the screw.
You can see where I tapped into the wastegate line for the boost reference. Just so we're clear blow off valves and wastegates are completely different in reference to this thread. I've had a bunch of people ask me why I need a BOV since I already have a wastegate. Also the valve is just tapped into the boost reference for the wastegate, it it has nothing to do with the wastegate operation.
This valve actually has 3 ports coming off of it. The clear(ish) hose use to run into the port that is attached to the black hose from the wastegate boost line. The valve used to get its boost reference from directly at the port opening but as I've said I noticed a lot better valve operation taking the boost reading from the other side of the intercooler. So that is why that one port is blocked off.
The 'drive pressure' port is right underneath the screw.
Hey guys we could all just buy one off this guy for $200 http://www.duramaxforum.com/forum/sale-section/109057-fs-blow-off-valve-setup.html :roflmao: notice how the dates correspond, wonder where he got the idea?
http://www.duramaxforum.com/forum/g...2-gonna-put-together-bov-setup-weekend-4.html some more interesting reading...i especially like post #7 and how he never give a shoutout to chevyburnout for the idea....
You realize this concept is not new, don't you? In this thread, I posted a link to another thread on this forum that discusses this idea and has results from someone actually doing it, is over 2 years old. There is also a thread from CompD that I linked to in that thread that is over 3 years old. I'm sure there are guys that were doing it even before that.