thanx man well i did have it blocked but ended up mstripping carbie and starting fresh again without it blocked and it is working fine atm

Haven't read all the replies but if your running blow through you need to run a line from plenum to fuel bowl[if bowl at atmo pressure as boost rises it will lean out, fighting the fuel pump]. Some pressurise whole carb bar inlet.Someone hopefully mentioned it.

ok guys so it seemed like it was working fine that night i got it running again but i stuck it back on the dyno and it is running leaner than b4 then i noticed wen i tried to thrash it a bit it was still striving for fuel..... :( i thought i had it all sorted

cranky yes it was mentioned but no one has said to run a line from my manifold into my fuel bowl although wen i first had it on the dyno we had a tafe lecturer there and we did tap a hole into the fuel bowl but only to outside the carby we didnt run a line off it to the manifold so this is wot i need to do tap that hole out again and runn it to the intake manifold. . . ?

Yes mate that is what you need to do.
You need the pressure in the fuel bowl to equal the manifold pressure.
The basic working of a carbie is that the venturi effect caused by a change in carbie cross section of the air flowing through it resulting in a pressure differential between the fuel bowl and intake air (look up the equation for Mass flow of air - mass flow does not change nor does density as at this velocity it is considered a non compressible gas, so a change in cross sectional area has a resultant change in pressure and velocity), end result, fuel moves from bowl to mix with air due to the pressure differential. In NA cars the reference pressure is atmospheric (i.e little hole on top of carbie is vented to atmosphere and the only pressure change is the caused by the venturi effect).

However, in a blow through turbo situation the reference pressure should always be the inlet manifold pressure, this is because on boost the reference pressure changes as the inlet air is no longer base lined on atmospheric, as it is being compressed by the turbo. In this scenario if the fuel bowl pressure is left at atmospheric then you have a higher pressure of air pushing against the fuel, you may even see the fuel coming out of the reference hole on top of the carbie.

If the reference pressure between air flow and fuel bowl is maintained, then the only variable is the pressure change due to the venturi effect, this will result in the carbie work the same as NA, regardless of the reference pressure. The other issue here is fuel pressure, which I think you have already rectified with a raising rate fuel pressure regulator.

Sorry if it is overly technical.

Bryan

no this helps alot thanx i will hopefully fix this tonight and let u kno how i go...
it's all making more sense now thanx. .

Does your fuel pressure regulator work on a vacuum? What I did was use a vacuum regulator, used the old emmisions fuel line (the one that emits fumes from the tank to the carb) as a return line. Got rid of all that crap that sits on the top of the fuel tank and just directly connected that line to the top fo the tank.
This way, when car is at idle, you have vacuum to open the loop and return fuel back to the tank. At full boost, it will force the loop closed and raise the fuel pressure to your carb. With this system and your Holley Pump, you should have no problem overcoming your boost leanout. As long as you do not boost more than your pump.
I was running 10 lbs. of boost on a 14 psi ProComp pump with no lean out.

well i ran a new fuel line from the bottom of my fuel tank with filter and pump then to front of car with another filter and then the fuel reg and used my old fuel line as a return and i have my fuel reg vacum to my manifold and that did nothing it wouldnt give it enuff fuel so i had to adjust the reg the screw all the way in for it to b driveable and i checked it with a fuel pressure guage and its running at 15 psi all the time

but still leaning out under boost

Line to fuel bowl tapped off between turbo & carb [not carb & engine]. Mcgee's right, just long winded. How about drawing a diagram of set up?

ok so i did this last night but couldnt test drive it very well because it was now misfiring down low i think cause of over fueling so tonight i will go buy some smaller jets for the primary
and c how that goes..

Sort your fuel pressure out first before you stuff with other things. If you can't get fuel pressure well below 15psi at idle, something is wrong. Its not your pump or regulator themselves but its more thank likely how you have your regulator connected