14B MAX RPM boosting???
 

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.

Re: 14B MAX RPM boosting???
 

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

Re: 14B MAX RPM boosting???
 

Will a big 16g work as a great replacement?

Re: 14B MAX RPM boosting???
 

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

Re: 14B MAX RPM boosting???
 

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..

Re: 14B MAX RPM boosting???
 

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

Re: 14B MAX RPM boosting???
 

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...

Re: 14B MAX RPM boosting???
 

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

Re: 14B MAX RPM boosting???
 

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?

Re: 14B MAX RPM boosting???
 

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

Re: 14B MAX RPM boosting???
 

not tryin to be mean but wtf?
pipe diameter won't cause his boost to drop off.


what plugs you runnin, and whats the gap?

Re: 14B MAX RPM boosting???
 

I have the stock NGK R's still but I have gapped them to .028-.030.
If I am getting on to the interstate I can put it in 4th gear and mat it and it will hold the boost steady throughout til 5K,
Then if you continue to hold on to the gas the boost drops below 5psi and surges up and down but no mmore than 5psi.

Re: 14B MAX RPM boosting???
 

what's your oil pressure look like?

And have you checked all the charge pipes? maybe you have a boost leak?

Re: 14B MAX RPM boosting???
 

i assume you did retard the timing at the distributor

Re: 14B MAX RPM boosting???
 

I have not retarded my timing yet.
This could contribute to my problems?
I do have a MSD BTM but I haven't installed it yet.

Re: 14B MAX RPM boosting???
 

i would do that before anything, even driving it. ---- man
actually i'd sell both the MSD BTM and the AFC and get your ecu chipped, and have money left over

Re: 14B MAX RPM boosting???
 

i run my 14b to 17 psi all day long, d16y7


runs full boost to redline.

14b's are great street turbos since they spool up nicely in the low 3k's

Re: 14B MAX RPM boosting???
 

When did I say that? He was asking about pipe diameter in an earlier post, I told him it shouldnt be an issue

Re: 14B MAX RPM boosting???
 

oh, well then, schwenk, wtf??
like i said your gonna have to do something about timing, if it still happens then. who the ---- knows

Re: 14B MAX RPM boosting???
 

And post some pics of your setup!

Re: 14B MAX RPM boosting???
 

I unplugged my wastegate and It failed to boost like I thought a open wastegate should. the spool time was
awful and the PSI dropped of a pound or two then with my mbc. Cold the problem be that My wastegate is a piece
of ----? Is it possible that air is leaking past the flapper and thats why I'm the seeing these results? I think that I am going
to try and put some washers between the base of the wastegate and the compressor house to pull the rod tighter
and see what happens. :S :S :S :S :S :S :S

Re: 14B MAX RPM boosting???
 

It's the fookin wastegate. I put three washers to one side under the wastegate to space it out and just tightened that one side down and it boosted uber fast. Then I knew I was on the right track then, so i took and tried to put 1 washer
per side but after making a couple of passes that mfer was hot as ---- so I was only able to get on 1 washer. The results were that I ended up plugging the wastegate back into the compressor housing and it is producing as follows.
1st--------6-7 PSI to infinity rpm now!
2nd ------6-7
3rd--------7-8
4th--------7-8
5th--------8-9.
Finally it's carring the RPMs to past 5k and to redline like it should. Haluah!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
What a pain in my ass but at least I found out wtf was going on.


Thanks guys for all of the brainstorming Ideas!!!!

Re: 14B MAX RPM boosting???
 

He's a tard after all!!! :o