My car has rubber mat not carpet - does that make it a 170 or 770 series?

For some reason Rockauto says the vacuum advance for 170 engine is only for 770 series ?????

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76 Dart

Probably a 170, depending on the rest of the car's trim. The VIN is a more reliable indicator of what the car is.
The trim level (170/770) does not affect the vacuum advance application, no. It is also unlikely RockAuto has a vacuum advance that will (directly) fit and work in your '61; the '60-'61 cars had a nylon vacuum advance line flared at both ends and secured with a threaded fitting into the carburetor and distributor ends. The '62-up nipple-type vacuum advance can be used but you'll have to cut off the nylon hardline near the carburetor and attach a rubber hose to it, then run the rubber hose down to the new vacuum advance. This might be a good time to consider upgrading to electronic ignition rather than putting any money or effort into the points distributor.

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一期一会
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