The term "cinder block" implies a much weaker construction material when compared to what is termed a "concrete block". I have successfully used concrete blocks for this type of auto raising duty for years. Have always used the block with the holes pointed up and cover with a 1" x 8" piece of lumber to effectively spread the load out over the available top section of the block. Remember that industrial buildings are constructed of this material and it holds up very large loads, just need to keep it in compression and not have sharp load points.

Even large wood blocks should be topped by a sacrificial 1" x 8" to prevent the main block from being split by sharp load points.

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1961 190Db retired
1968 220D/8 325,000
1983 300D 164,150