It's a 2001 4.8 on a 220/220 camshaft with a 76mm magnum turbo pushing 10 lb's. The truck pulls good 1st to second 2nd, right now its reading like 9 lb's since i got a cutout open but shifting to 3rd gear it looses around 4 lb's of boost.

Why its this happening?

4.8, 220/220 cam, magnum 76mm, 10 lb's, 14* of timing, on 93 pump gas.

 

Just need to clarify real quick. Does it only happen headed into 3rd? Any chance of getting a video?

 

Yes only happens going into 3rd
I'll try and get a video.

 

Sounds like the wastegate is much happier with the cutout

 

^^^So it's fine that it drops from 9 lbs to 6 lbs going into 3rd gear.
Does she looses power?
I will like to know why the lost of boost at that range.

 

Usually it's the other way.
What's the rest if the exhaust ?
What's the gate size?

 

Its fine, arr you just running off the spring or are you using a controller? The gate only cares about the pressurr on either side of the valve. A cutout lessens pressure after thr valve so it now flows more. The solution is to close the wastegate more (stiffer spring). The turbo doesnt care what gear you are in.

 

It's a jgs400 wastegate and I'm running off a controler.
I have the 5 lb spring even with the cutout close I loose boost.

 

Actually it sounds like you have a boost spike issue. 5lb spring should be 5lb of boost. The fact thst it returns to that means its working just fine and you have your gate open pressure too high.

 

I turn the **** down and it was boosting 5 lb's the I turn it up the **** and got 10 lbs.