schwenk

Civic
ZC DOHC
450s
14b
AFC hack

The problem that I'm having is when I get to 5K rpm the boost kicks out like the turbo has huffed out of air.
Is this the most that I can take the 14b?
1st---6K rpm
2nd-4th----5k rpm

Any help would be appreciated.
Or just let me know if I'm looking in the right or wrong direction.

QikEnuF

You are running the compressor out of its efficiency range.. Go bigger

schwenk

Will a big 16g work as a great replacement?

QikEnuF

Sure man. Pretty much anything is bigger than a 14b

losesomethinbra

What psi are you running? I was under the impression that a 14b should be able to hold at least 8-10lbs all the way to redline on that motor..

schwenk

I am running 10 psi.
Even when I run it at less psi its still the same result.

turbob16hatch

then something is wrong with your setup. my friend had a 14b on his built z6 and it pulled to red line at 20+ psi.... way out of it's efficency but we were just messing around...

MAJORAHOLE

ya, dsm'ers run them at 17-19psi all day long. i'd get a ------ chipped ecu man. most likely ign timing

schwenk

See that's why I was like wtf is going on. I have heard of people raping the hell outta these turbo's.
I am going to try and do some diag on a few things and see what I can come up with.
It's weird as hell because it will hold boost steady then just drop off like you let of the throttle @ 5K.
Another thing, could it be because of too small of a diameter of piping on the charge side?

losesomethinbra

It holds 10psi and then drops off? That is weird. If your charge pipes are at least 1.75 inches you should be absolutely fine... Make sure there are no leaks in the charge pipes, intake manifold, or exhaust manifold.. Whats your exhaust like? Excessive backpressure can restrict spool at higher rpms.. Also where is your wastegate or wg actuater getting its boost signal from? It should be a dedicated line. Same for the bov if you have one installed

If everything appears in good shape I'd look closer at the turbo. Did it run ok before you got it? Id imagine when they get worn out they probably dont like to spin, but I havent any experience with worn out turbos maybe someone else can chime in