You have the choice of many different brands and models to put on your Volvo. On my 5.7, I have run the stock Volvo AL prop(21). After 10 hrs I switched to the Raker(20) I had on my outboard, Had to get the rubber rub changed. For the past 10 yrs, I have been running a Mercury Enertia(20). The Dia of all three propa re different, as are the Rake, Cup, and blade area.
In the mid 80s I bought a Mercury brand SS for my 115hp merc. Compared to the AL of the same pitch, the SS was either a 1/4" or 1/2" larger in Dia. My rpms stayed within 50. the speed was within 1/2 mph. The SS had a bit more Rake and slightly more cup and did hold on better in turns at higher trim settings. Neither prop was a 'Performace Prop' That was over 30 yrs ago, and great strides in prop design and performance have occurred.
The SS vs. AL debate has been going on for over 40 yrs. SS is about 5 times stronger than AL, so blades can be much stronger, or they can be much thinner with the same strength. Some SS props are on one end of the scale, others go the other way. Usually it a combination of thinner blade but still tougher than AL. Thinner blades are more efficient and the extra strength allows for more complexity regarding blade shape. The extra strength, does have an Achilles Heel, AL props often, upon impact, break blades off. SS, being stronger tends to bend. The day I put my SS on the VP, I found a ridge of rocks about 20 inches under water, I was only going about 22 mph but it tore the blades of the SS prop and bent the propshaft.
