13:1 Compression Pistons in 340 Small Block

If you have access to a source of consistently blended source of e85 it becomes slightly more feasible but your going to burn more of it than you would race gas. If it’s mostly a summer driver, you don’t have to worry about the ethanol blends varying more than a few percent, but in the winter, it often gets blended to about 65% ethanol. The 78%-85% range is regarded as the sweet spot for that level of compression. But it’s really going to be about if you can afford to feed it.