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Discussion Starter #1
Hello my friends; I am really exited about doing the mod with the washer on my valve,but I am confused,few questions please.

I have an 83 turbo in perfect shape,I just want a hair more "PEP". My boost valve shows almost to 7 inches in full aceleration but it nevers get there. I dont think I ever heard the valve open. How can I get more boost then ? Would you take a few mjnutes and e mail me and let me know before I start. I would think making the spring stronger will make it worse.

Thanks a lot,

Jorge
 

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Hopefully this will clear your confusion.

The pop-off valve is a safety device designed to vent the manifold in case of an overboost situation, like if your wastegate gets stuck closed. The valve does not regulate your boost pressure, this is what the wastegate does.

If you want to raise your boost for more performance, you need a boost controller on your wastegate, be that a bleed valve, manual boost controller, or electronic g-whiz boost controller. In order for the boost controller to do it's job, you have to raise the pop-off valve pressure, which is set to about 8-9 psi - you cannot raise the boost until you raise the pop-off pressure, hence install the washer and make the pop-off tighter.

The pop-off modification will work up to about 10psi or so, then there is not enough flow area to limit the boost - I found you can accomplish the asme thing by using the spring from a 300ZX or 200SX turbo pop-off valve inside the the 280ZX pop-off valve in addition to the stock spring - if it's still not enough pressure (mine hold to 11 psi right now), you can add a smaller washer, still keeping the flow ability of the stock valve.
 

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you know your both dumb just get forged pistons remove your pop off valve and add performance to your cars. Its a lot better because a stock 305 can smoke a stock 280zx and thats a big problem when a american car and smoke a forgien car.


tbs
 

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Moronicus speaks...

Truthfully, I don't know who breeds these guys.
I plugged my Emergency Pop Off valve as the chance of overboosting is directly related to how innattentive you are to your car and it's performance. Using a largediameter tube to a good mechanical boost gauge will let you know in plenty of time to LIFT YOUR FOOT. That is the ultimate boost controller. If your wastegate sticks, lift your foot, drive gingerly until you can remedy the situation and move on. That stock thing is there for guys who just romp it and tromp it. (Like someone who actually OWNS a stock 305 V-8) If you know what your car is doing, that thing is more of a performance hindrance as a possible boost leak than a required item. You don't really need it. It will only cause problems. You can live fine without it. BTW, anybody ever actually READ the factory service manual? They actually have listed as a PROBLEM the following: "Excessive Engine Power"

Excuse me, since when is "Excessive Engine Power" a PROBLEM?!?!?!?!?

BTW I once surged my compressor at 21 pounds of boost. So you get away with being young and stupid only ONCE from my experience, after that, learn to lift the foot! ;-)

ZYA!
 

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Discussion Starter #5
Hello Turbo,thanks for calling us dumb,I am glad that you are so well educated and have such good manners.
Have a nice day,
Jorge
 
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