Diagnosing boost problem 1.6TD

[16vjohn]

I have an NA engine that I turboed using all factory equipment (k24).  I left the NA pump on there for now.  Before, I had all this stuff on a rabbit diesel and I was able to hit 15psi simply by turning the fuel screw up on the NA pump... Now I can barely hit 10psi on my current setup.

I have double blocked the overboost vale... I put a cap on it AND modified it so that it won't open.  I double checked for leaks on the 90 degree intake hose.  It appears that all my gaskets are in good order.  I KNOW the turbo is capable of atleast 20 because that's what I was running on my rabbit.  

The only difference between this car and the rabbit is this car has a full factory exhaust.... the rabbit was straight piped with 2.5 inch after the downpipe.

On the rabbit I tuned the timing by ear and by performance... To increase IDI performance can you advance or retard timing?  Also, what do you figure the max boost capability is when using a NA pump with fuel screw tweaking?

[saurkraut]

Put a wrench on all of your exhauste manifold nuts.  The exhaust manifold have a propensity to potatochip and back them off.

Might be tough getting to 20 PSI with a nonturbo pump.  I think you may run into problems turning up the fuel screw and lowering the idle.  The idle screw is actually the resudual fuel screw, and it will tend to starve the engine for fuel when you let off the throttle after accelerating.

The majic of the turbo pump is the LDA pin.  Do what you have to and get one.

[16vjohn]

Good idea... I'll check all the bolts again.

I have 3 complete TD engines, I am just really dreading the pump switchout.  I need to get a timing belt kit or atleast the dial indicator.  Guess I might as well do it since the t belt is due anyway.