The ASP 40's of that era were very robust and were ABC type. They were very popular among our club members then and was the standard engine first used in our Sig Kougar racing class. When the 46 came along it became the standard.

They were screamers and very powerful engines that ran right out of the box, and performed best when fed 15% fuel with a castor/syn blend on a 9x7 or 10X6 props.

Karol