How on earth do I adjust base idle on this car - everytime I put foot on brakes it revs down to almost dead then comes back up and just really rough under 750 thanks

sounds like your idle speed controller is the problem, there is an idle speed adjust screw on the throttle body but it must be set lower than the target idle speed controlled by the ecu, u adjust this by unplugging the ISC and then winding the screw in till the motor just idles, about 3-400rpm
then when you plug the ISC back in it should idle about 700 ish

you could try cleaning the ISC by unbolting it and flushing it with carbie cleaner.

failing that you made need a new one

is the ISC the think with the black knob on top of the throttle body

yeah, ISC= idle speed controller

the black knob is actualy an air filter

have cleaned it all out with degreaser no change - i will try adjust the screw with isc disconnected and maybe try the steps to adjust the voltage TSP or that stuff that people mentioned in is that how it's done but otherwise i will get a new isc

This happens with my EL Ghia too,
but with mine, being that I have a stage 2 cam, it could be interrupting the ECU and how it computes everything, but it shouldn't because the ECU is tuned according to the cam.
I'm not quite sure what the go is,
sounds cool though.
Old school metallic cam idle.

Mine also revs up high (around 2000-2500rpm) every now and again when I just rev it.
It stays up in that rev range for about 15 seconds, then drops back down to base idle.

All of this happens to me AFTER I cleaned out the ISC and throttle body butterfly etc with carby cleaner.
It's certainly odd.

Thanks mate, I got rid of the EL Ghia, I came back from holiday and somehow the camshaft gave up when I was on the road so maybe that was the cause, it was on its way out but ended up deregistering it and got rid of it. Now I have a nice AUII Ghia and things seem to be going according to plan with it - but a bit of a unstable revs at times but still better - so will see how far this one goes. thanks anyways