First I might start by saying i needed one for the turbo bark. I know most people say diesels dont need one because they dont have a throttle plate. but a bov on a diesel and a bov on a gas are too differnt to compare. Gas engines need them to throw the air away asap as not to break the shaft of the turbo or burn the bearings because theres absolutley no escape for the pressurised air.

Diesels need them once you start running higher boost and barking the turbos. If you do it often even though the air escapes through the engine its not fast enough for that much pressured air to escape or for my needs as its still barking the turbo.

After seeing all the electronic diesel Blow Off Valves i didnt want that stuff and it wouldnt work for me seeing as my tps is bad and i use a pot as the electronic diesel bovs run off of the tps. The price was a bit outragous also.

With my hx50 i get some pretty good bark and some other wierd noises some times and didnt want to kill my turbo. So I started researching and using previous knowledge of all the turbo gas cars ive owned and built and i got a bov for a regular gas car to work on the diesel with just the boost line, No vacuum, as its a sequential blow off valve and works off pressure spikes.

So after hours of adjusting and test running the truck I got the blow off valve adjusted to open as soon as it sees any pressure drops to regulate the pressure in the intake. It also only opens for just a second as its pressure regulated and not vaccum.

Total cost to do every thing was 110 bucks. and only fabrication tool needed was a hacksaw to cut piping.

The sound as 40psi is pretty crazy when the bov opens

 

sounds pretty cool and cheap. I've been kind of curious about tryin one. Can you make a list of the parts you used and where you got them too?

 

Im thinking if you ran the BOV off drive pressure it may open a hair faster seeing as it would be a big fast fluctuation of air instead of a smaller one which would move the valve faster. Both would work near the same.

Heres from HKS website.
www.hksusa.com/products/more.asp?id=792


The HKS Super Sequential Blow-Off Valve (SSQV) is a dual stage pull-type relief valve. Unlike typical push type blow-off valves, the SSQV will not leak under any level of boost because the boost pressure in chamber "C" keeps the valve closed against its seat (Diagram 1). The SSQV releases excess boost when there is a pressure alteration in chambers "A & B", not by the rate of boost pressure or vacuum in the line. This ensures a quick valve response and complete closure during idle. Many competitors use a push-type blow-off valve design with a large valve to accommodate high boost / high horsepower applications. These large valves react slowly and require high pressure to open, and are not able to activate and prevent compressor surge at light-load conditions. On the other hand, smaller, fast reacting push-type valves do not discharge the airflow capacity required for high horsepower applications and tend to slowly open and leak as boost pressure overpowers the spring. For maximum performance, the HKS SSQV incorporates both a small primary valve for ultra quick activation, and a larger secondary valve for additional discharge capacity. The SSQV is engineered to initially open the small primary valve at light throttle and load conditions (Diagram 2), then sequentially opens the secondary valve for additional relief capacity under high boost and load conditions (Diagram 3).

 

only thing i used was the bov, a fitting to tap into boost. and some nylon line. hardest part was adjusting the valve correctly as there isnt much adjusment on an ssqv u can do but the little adjustment there is was tricky