Is this a streetcar or a racecar? From everything I've heard slidevalves have a tendency to stick from dirt and grime that builds up in a streetcar. Since a racecar gets much more maintence and squeezing every ounce of power out of a more is critical, it's much more applicable to them
Frankly, this sounds like a pretty big job, you should be able to get your throttle bodies rebuilt for around $900. It's not cheap, but it's like having a new set of throttle bodies.
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