18 Stainless vs 19 Aluminum I need suggestions?

[akareddog95]

I have a 1984 Procraft fish and ski with 1984 Suzuki DT115. I bought the boat last year and it came with 3 X 13 X 19 Aluminum prop. The boat is set up prefect with the aluminum prop. It runs right at 5500 RPMs at full throttle. Top speed is 40 mph. I found a killer deal $150, on a brand new Suzuki 13 1/4 X 18 stainless steel prop. What affect will this have on my boat? I know 1 degree pitch usage means an extra 100-200 rpms. But I have no idea about what Aluminum to SS is going to do. I mostly fish small mud lakes in Nebraska. It's 100% fishing boat, no skiing. I don't have a spear prop and this sounds like a great deal. Thanks for your help. Shane

[D'oh999]

An 18" sounds perfect. SS don't flex as much as Aluminum, 1" of pitch plus the extra cup on SS should be exactly what you should run.

[akareddog95]

Thanks 999, I when ahead a bought it. I was so confused, some post said to go down 1" and some guys say to go up 2". I don't see how can get hurt if it doesn't work, $150 for a new SS Suzuki prop.