Well done.

Will you be testing the new set up once fitted to see if the problem has definitely gone?

You might get an indication by getting the engine fully warmed up, let it idle for a minute, then BOOT the throttle, easier with a helper to see the exhaust output.  Well done in persevering.

  good work to find that out with some patience involved as well 

I'd be inclined to leave it out.

Does sound a bit odd.

I had a similar issue with my standard radio turning on by itself but mine wouldn't even turn off with the power button. I replaced it with one from eBay - a relatively cheap and easy fix

Yesterday we fitted the Toyosport manifold and new main CAT and it now revs properly.  Clearly that was the answer all along, the pre cat in the right downpipe had completely disintegrated and blocked the main CAT.

I guess the question now is whether bits were also sucked back into the bores giving us a car with a serious oil drinking problem. On the face of it the engine seems ok.  On start up there is lots of steam but after a few minutes it seems to run clear and idles smoothly.  I'm hoping the previous owner experienced a catastrophic CAT failure event which rendered the car immediately undriveable such that bore damage was limited......is that even possible?

I guess that we wont know until we get the car on a road test and we are currently a long long way off that.  Suspension, brakes and power steering all need an overhaul plus misty headlights and some rust issues.  I'm sure I'll be back on here asking more questions soon. You lot are amazingly knowledgeable, thanks so much for sharing your wisdom.

Well done for perseverance.

The standard radio in my 2003 roadster always turns on and raises the aerial when the ignition is switched on. If I turn the radio off, turn the ignition off and then turn the ignition back on, the radio will turn on and raise the aerial.

Is this correct or do I have a fault?
I would have thought that if I turn the radio off it will remain off when I turn the ignition off and on again.

My 2003 roadster has suffered from a flat battery if not driven every few days.
First I replaced the battery but the problem continued. To diagnose the problem I disconnected the negative battery lead and connected an ammeter between the lead and the battery. With the ignition off and all doors closed, the car was drawing around 200 mA. I removed every fuse one at a time from the engine bay fuse box,  the fuse box at the passenger side of the dash ("RB3") and the fuse block under the front bonnet. No fuse reduced the draw significantly. The drain remained high. I eventually disconnected the alarm siren which is located in the frunk in the spare wheel storage area. This immediately dropped the current draw down to around 20 mA. I am replacing the alarm siren with a secondhand unit and have bought new batteries for this from eBay. I hope this helps others who might have the same issue.  Here are a few pictures of the faulty siren