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01 Jetta Blow off/Diverter valves

2445 Views 13 Replies 7 Participants Last post by  Anthony

New here, new to VW..

Picking up my 01 manual Jetta Monday. Super excited, it'll be my 2nd car. 1st was a Dodge ram 2500. Gas Guzzla!

Anyways, I got about $1200 I can work with for mods... I'm thinkin' chip, intake, turbo back.

I have a quick question.. I was shopping for BOVs because that's going to be one of the first things I want to put on, however, been searching around and a lot of people are saying BOVs are no good for 1.8ts.. So I am doing a bit of shopping for DVs now. Only thing is, I heard DVs arn't as loud as BOVs. This is a problem, I want my compression blow off/charge-air or whatever you call it to be loud... But I also don't want to cause any problems to the turbo... Or anything else for that matter.

I found this BOV/DV from Forge... I don't know anything about it, so I was wondering if someone could tell me if this is a good idea.

Now it's ok if you want me to search and find out but it'd be cool if someone could explain real quick BOV vs. DV.

Also, if that bov/dv from forge isn't the best can someone show me to the best or "LOADEST, SAFEST" Diverter Valve out there. Again, I have $1200 bills I can work with, so I could put a good bit down to the DV.

Don't know much about cars or VW, and super excited to join you guys on the road. Sorry if this is in the wrong thread or if there's hundreds of these threads (i tried searching).

cant wait to hear from you,
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A compressor bypass valve (CBV) also known as a compressor relief valve is a vacuum-actuated valve designed to release pressure in the intake system of a turbocharged or centrifugally supercharged car when the throttle is lifted or closed. This air pressure is re-circulated back into the non-pressurized end of the intake (before the turbo) but after the mass airflow sensor.

A blowoff valve, (BOV, sometimes hooter valve, dump valve) does basically the same thing, but releases the air to the atmosphere. This creates a very distinctive sound desired by many who own turbocharged sports cars. Some blowoff valves are sold with trumpet shaped exits that amplify the "psssshhh" sound, as not all bov's are the same, some make different noises and these designs are normally marketed towards the tuner crowd. For some owners this is the only reason to get a BOV. Motor sports governed by the FIA have made it illegal to vent unmuffled blowoff valves to the atmosphere.

It's really your choice here. just gotta watch how you install it or you can run into problems with your ECU.
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you got the idea


with a BOV you might also run into legality issues. I would do some research before making a decision
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