Biscuit vs. Spool Motor Mounts

67Dart273 said

One member here put on a pretty good rant claiming that the old style mounts were better than spool mounts for torque. But I have no idea where you ACTUALLY get QUALITY pillow mounts, anymore.

When I had my car together, I converted to a spook K, and it was my impression that the mounts reduced header clearance, and I remember a fight trying to get to the drain plugs in the block.

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So a mount that can literally pull apart under torque leaving the whole drivetrain free to lift is better than one that can’t? Because ultimately the spool mount retains the bolt, if the bolt isn’t completely loose. I’ve literally watched an old 318 try to climb out of the engine bay of a power wagon when the drivers mount failed. It was shocking how much that engine moved.

The block drain plug access definitely sucks with the spool mounts, it’s not impossible to get at them but if you’re trying to break a plug loose forget it, you won’t get that kind of torque on the plug.

I think the biggest indicator is just all the header threads. The Doug’s D453’s are probably the best example, it seems like they fit the spool mount cars pretty well, with some folks reporting they did nothing to get them to clear. But with the biscuit style mounts a lot of people shim the mounts to raise the engine slightly for clearance.

Now, I’m not saying the factory changed the crank centerline, but maybe all the reproduction biscuit mounts are shorter than the factory ones were. Or maybe they’re more likely to sag a bit when tired, lowering the engine.