I will say, I'm having second thoughts about the intake issue, for the specific reason that you described the problem as stalling
upon a stop, i.e., upon deceleration, rather than stalling upon idle. Is the behavior that the engine stalls as you decelerate, or is that that you come to a stop and then are sitting there and at some point it stalls?
If the behavior is the former, it might still be carb-related, because most people who report that problem find that the solution involves the carb. Zenith owners sometimes describe this behavior – something about the fuel sloshing in the bowl as the car decelerates and starving the engine. Here's a quote from someone on this forum a few years ago.
Quote:
Originally Posted by Mark in MT
My experiences with the Zenith are that if you are idling too fast, it is not running on the idle circuit. This can be because the throttle plate is not positioned right in the bore. If the air at idle is not forced right by the discharge port for the idle, you have to increase the idle screw to get it to run. This makes it run on the cap jet circuit which is more sensitive to sudden stops. Adjust the plate in the bore to get it to cover the idle discharge port and you can get it to idle at 400 rpm and do so while standing on the brakes.
|
So I dunno, it might be worth exploring the carb situation a little more before you buy a brand-new intake. You may have multiple problems – a tiny leak in the intake that's making it run a little bit lean, but also a problem in the carb that cuts the fuel flow on deceleration.