All of the upgrades would have to be internal.
We cannot use Webers in Cali because the do not have an E.O.#
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We can't mix and match carbs (Pinto carb on Isuzu engine etc.)
We also have to use stock ignition components, unless the have been approved by CARB and have an E.O. # for your vehicle.
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They also check timing during the emissions test, so that option is out also
. Here in Cali we have to keep 'em stock.