What is a Blow off valve or bypass valve?
 

Hi, from what I've searched and read, I still am unclear about the difference between the blow off valve and the bypass valve.

I have a 1981 280ZXTurbo with 63,000. Everything is just stock.

Now I'm starting to do some modifications to it. Beginning with IC and higher boost.

I know that I must have a Blow off valve if I want to go higher boost. But I also read about a bypass valve ?? Is that the same thing? Which one is better for my ZXTurbo? OR.... should both of them be installed for my car?

Furthermore, to go higher boost, I would need a boost controller or something sort like that, no? Where can I get all these items: Blow off valve/Bypass valve and Boost Controller? Do you guys have some links that are pretty decent (cheap) price?

Thanks in advance,

Nathan

sounds like the same thing, it's too long to explain, so read this...

http://auto.howstuffworks.com/turbo.htm

ok, they don't mention BOVs or Boost controllers. the BC works with the wastegate, in order to control how much boost is being made so you don't "blow up" the motor. the control can either be electronic or manual. like atop speed limiter but for a turbo, a boost limiter.

the BOV is a valve that works w/ the vacuum of the motor. when making boost & then you shift, the butterfly valve inside the throttlebody closes, imagine walking into a locked door at 30mph. now all that boost has nowhere to go but back into the turbo itself, this is very bad. the BOV opens when there is vacuum inside the intake manifold (past the butterfly valve) then the valve opens & releases the boosted air. that PWOOSH sound you hear on turbo cars.

280ZXTurbo with 63,000. dang id ebay thay i seen them get 10k+ w/ those low miles

I just Installled a manual boost controller on my 280zxT
am boosting 9-10 psi to be safe W/O Intercooler. I got My Manual boost controller From e Bay (turbonetics) For $40 Bucks You Can also Get Greddy BOV For $180 Plus u Have To Also Buy A universal Flange To Install It, Its About $30 more Dollars. I guess you Can Search In Ebay Maybe Get A Good Deal.