LT4 Boost Bypass Valve Adjustment
 

Some forum members have stated benefits from adjusting the boost bypass valve. I found a Youtube video showing the location and how to adjust the valve to ensure that the bypass doesn’t prematurely open and lose boost for an LSA. I can’t locate information on the LT4.

The following information would be helpful:
1. Post a picture of the bypass and the location in the engine compartment.
2. Explain the “adjustment” procedure.

@Lt1z350 You seem to be a proponent of this, but your post aren’t descriptive enough in other threads. More info would be greatly appreciated.

So cooling mods, adjust the bypass valve and some other unknown trick and you're running .2+ seconds faster on average than every other "fast" stock A10 pass? I'm probably game to try it, but I don't see how a bypass valve adjustment is taking you from 7 PSI (Stupid low for a stock LT4) to 10-11+, in fact that's not possible IMO without a pulley. What gives? Also, I thought the stock tune wouldn't even really allow the car to make any more power, hence why adding intakes/throttle bodies and the like on stock tune don't, in your opinion, gain anything because the tune just limits the timing and whatnot to keep it at stock power?

I just went and checked mine. It was blue lock tite'd in place. I backed it out and it basically immediately lost contact with the little arm for the canister. I screwed it back in until it JUST touched. I MAY have it 1/8-1/4 turn further out than it came from the factory.

Notice any changes? Did you check boost before so you know what it goes to after?

Pics of the Parts being discussed would be helpful.

This is what you're looking for. It is the solenoid and metal rod assembly. To the right of the pic under the coolant cross over is an allen head screw with blue loctite. This is what you'll adjust.

Reference Picture to put you in the area.
https://i.imgur.com/bd3shiJ.jpg


screw and GAP
https://i.imgur.com/8eRPryd.jpg

One more shot
 

Here's another pic.
Front of motor, right behind TB.
LOL, Almost life sized too.

I havent gone and driven it yet.

im not expecting anything though as I believe mine was probably set correctly from the factory if its supposed to have 1/16" pre-load, I would guess mine did.

Wouldn't expect a lot unless it's gross off. The bypass blade should be slightly "off seat", to avoid grooving and a possible binding. Probably around 1/8th of a turn off seat will handle the job.

I made this same adjustment on my Gen5 ZL1 and I felt the difference. Going to try it.

I am still not sure what I am looking at when I adjust sink don’t do something wrong. Can someone break it down detailed if they have done it. Also if it’s so popular why is there no videos for an lt4 on YouTube

There are videos on youtube for the LSA, same concept.
-Bobby