I added the RB downpipe and presilencer with stock y-pipes and mufflers.
My boost doesn't seem to have changed at all. It just goes up to about 5psi.
Am I suppose to have higher boost with these upgrades?
I have an aftermarket Boost gauge btw.

 

Your wastegate is probably ported and prevents boost creep/ uncontrolled increase. This is a good thing. You will need a boost controller to raise your boost pressure and make more power. I'd suggest a fuel pump replacement if you are increasing the boost over stock.

 

Dang it i was about to post this! Ha , boost creep is a bitch, it was hard as hell to keep it under control with our old fd shop car and a single 44m...........we wound up running dual wastegate and a divided housing

 

+1 well said

 

I dont think the down pipe will allow your boost pressure to increase. Modifying the wastegate ie. boost cont. will up your pressure

 

as stated, boost controller is needed to increase boost.

 

In theory a freer flowing exhaust will cause boost creep

 

It's not a theory. Overwelming the wastegate will cause creep. And an unpredicted rise in boost pressure can cause the engine to run lean. That usually means a new engine and turbos.

To the OP: If your only seeing 5 psi, it's not a case of not enough exhaust flow...something is wrong with the sequential system or you have a boost leak somewhere.

 

I don't usually floor it. But i did a WOT pull on 2nd gear and my boost was 8 - 9psi almost reaching 10psi. It doesn't pass 10psi which I really like. I think the problem was that I didn't floor it all the way before. Also to add, I did notice a mpg increase after putting on the Racing beat downpipe and presilencer. I now get about 250+ miles on a full tank (maybe 300miles). from full to half i went about 150+ miles. When everything was stock, i was getting like less than 200 miles on a full tank. I also recommend an MSD 6A, it's on my my favorite mods.