What little mods can I do to make a 1200 a bit faster....In terms of exhaust,carburetor,extractor.
And would it be best to use 2-1/2''or 3'' piping for the standard 1200 engine?

The best exhaust pipe for a stock A12 engine is 1.5 inch. If you have a bigger carb, use 1.75 inch.

You would probably need 200hp for a 2-1/2 inch pipe ...

Is a 2" overkill with stock manifold ?

thats what i have and it's fine, i did it so it was ready for extractors. i say an 2" system with extractors and a 32/36 webber would be a good start. and a proper tune when you have your webber fitted

2" is probably optimum if you have headers and larger carb ... and do most of your driving at high rpms. A big exhaust pipe won't necessarily make your engine run poorly, you just won't get optimum acceleration.

General rule of thumb, the larger the engine, the bigger the pipe. For example:
- 150hp 3-liter engine: 2-1/4 inch single exhaust
- 150hp 4-liter engine: 2-1/2 inch single exhaust

But these are just generalizations. It depends on various things.

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