A lot of the factory cars have hung the boosters pretty close to the the engine with no problems. I've run into a couple where the booster has had to be moved to remove a valve cover.

In some cases (MOPAR comes to mind) they even made bracket assemblies that relocated the the booster up away from the engine for clearance reasons.

What might help is a picture of the engine side of the firewall to see what the clearance looks like there (if you and the engine and booster mocked up.


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