Problems With Ca After Turbo Swap

[Kaz200]

Ok I've had the flu all week so I'm like a blonde x2 mentally.. so bear with me.

The car's not making boost after we swapped the turbo and a few minor things...

CA18DET 180.. got it tuned then of course the bloody turbo blew later the same day.. So...

1) swapped from stock turbo to a slightly larger SR turbo (in VGC).

2) Swapped from stock AFM to RB20AFM, rewired plug.

3) Got some custom intake and intercooler piping done.

4) Added an RB20 plumback BOV (currently venting to atmo until we can get a hose to fit, and the return pipe for the BOV on the intake piping is blocked off)

5) Pulled apart and cleaned inlet tract (including manifold + TB) because it was full of oil from when the blown turbo (oil seal on compressor side).

6) fuel injectors cleaned while it was all apart

7) new liquid gasket through intake side + exhaust manifold to head

8) put in a silencer caus it was even louder than before.. like about as loud as a lawnmower (took it for a run without the silencer in today and it was running better but still no boost of course).

9) changed spark plugs, gapped to .7

10) Refilled oil/water blah blah. Will be changing oil again & flushing coolant after another run or two.

11) Changed SAFC settings to reflect rb20 afm.

When boost hits ~4-6PSI the car seems to hesitate/stammer (still revs but doesn’t boost – engine kind of choking on itself).

My guess is that it is a leak in the cooler piping somewhere.. but not too keen on pulling it all apart only to find that there's not. There is one stud missing on the turbo outlet elbow as it needs to be retapped.

We’re also uncertain of the current wastegate plumbing setup, not sure if this may be causing it.

It's also really, really hot under the bonnet, with most heat seemingly coming from the dump pipe. The Temp gauge in the cabin is normal, but engine bay temps are definitely up. The only thing that’s different that could affect it is:

1) Left off a few of the minor heat shields (ie small shield between the exhaust and compressor housings), and

2) The silencer (possible that the exhaust gas is heating the dump more than it used to because the hot gases are not escaping as quickly?).

Any other ideas/advice is much appreciated.

Hope that all makes sense.

Thanks guys!!

Kaz

[BH_SLO32]

Kaz,

The RB20 BOV isn't leaking? They should hold plenty of boost before leaking but I have seen a stock RB25 unit that had obviously had its day and start leaking under stock boost. If venting to atmosphere and running an airflow meter it will cause the car to hesitate as described and overfuel resulting in fuel being burnt in the exhaust (ie the exhaust gets hot).

You should be able to hear and feel the BOV leaking.

Let us know how it goes.

Hope this helps.

Cheers

Edited March 22, 2006 by BH_SLO32