Catalytic Converter Removal and Aftermarket Throttle Body

Do you have a V8 or V12?

Reason for the ask is that an larger throttle body for the V8 is in the pipeline. I have played around here in Australia and found significant improvement in the V8 but a waste of time on the V12. I have shopped the world and can't find anyone doing one for these cars so I am currently negotiating with a machine shop to have a run of them made.

Any preliminary interest would be good as numbers will make the difference to end cost.

As for cat removal on the V8 it does make a difference but the consequence on legality might be risky. Certainly is where I am although the temptation was too great to not try! Perhaps removing the internals with an iron bar and leaving the appearance will get you through MOT checks although ignorance of a burnt out Cat could still be risky. It's up to you.

cheers

Just curious, but is trottlebody the same as the intake manifolds?
Noticed that the same thing might have different names in various parts of the world.

I have a V12, and I've thought of having my intake manifolds and heads machined to a bigger size if they ever have to come off (i.e leaking gasket).

I was told that someone in Holland is driving around wit a bigger intake manifold on a V12, where the part of it with the BMW logo on (the common chamber) had been made bigger by splitting it and welding in a piece of metal.
A noticable power gain was presumably the result.

As one can see on this newer BMW V12 engine, the common chamber is bigger, so it makes sence to me that the power would increase.

The throttle bodies on the V12 are electronically actuated and are completely different to the intake manifolds. It is not practical to open up the throttle bodies on this engine as these are not a flow restriction.
The intake manifolds can be honed along the runners and port matched to the intake gaskets for a marginal improvement and a larger volume plenum chamber will give a greater volume of air for the intakes to draw upon improving flow, however this improvement would only be marginal.
A possible 1-2% increase can be found by removing the gauze and inserts in the MAF sensors but you will need to be very careful and keep the air filters clean.
Removal of the cats will net a noticeable improvement in performance but depending on your emission laws, may make the car illegal.