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Old 07-21-2019, 02:00 PM
WIX51348 WIX51348 is offline
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I'm not sure that all a backfire would do is stall or slow the rotors on the blower. I would imagine it could blow open hoses leading out of the supercharger and it could also cause a huge spike in pressure leading to the bowl and, if one is used, fuel pressure regulator, as these systems have pressure lines from downstream of the supercharger. I'm not totally sure what would happen if a backfire occurred between the intake valves and the supercharger, but I cannot imagine it would be good. If at low RPM, the inefficiency of the blower and it's lack of momentum would potentially allow enough slippage past the rotors and deceleration of the rotors that minimal damage would occur. If at higher RPM, however, the blower will have much less slip and the rotors will have quite a bit of inertia. If a backfire occured at high RPM, I doubt the hot gas from the premature combustion would have anywhere to go, and it could potentially blow the system apart. I would imagine the blower would be ok but the intake system would probably suffer damage. If the "explosion" ended up trying to go out the blower and slamming up against the rotors, they could potentially be slowed, in which case a belt drive would be preferable, as slippage would allow greater dissipation of inertia, whereas a chain drive would rather immediately take up the deceleration of the rotors, while the crankshaft continued spinning at whatever RPM it was at. This might snap the chain or strain the gearing in the supercharger, which one would be wise to avoid. I would go with a belt vs a chain given the potential for a backfire, as it may at least help prevent the blower from being damaged.

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