I have an 05 with 500efis and XR drives. Hit 79 this summer with 30p 4 blades. Boat came with 26p 5 blades and I was told it would hit 81 but that seems optimistic. Best I saw with the 5 blades was 75.

Mine will do 80 - 81 w 500 efi's and 4 blade 30 P props, XR drives, moderately loaded, in the ocean.

Bill, what year is your boat? Did it come with 5 blades and you switched to 4?

Mine is a 2000, came with labbed bravo 30P 4 blades (per Brett at BBlades Formula supplied labbed props on these boats). It has the higher x dimension also by the way since the 'Silent Thunder' box has a raised portion over each drive. I'm happy with these props, comes right up on plane just tucking the drives in and I haven't heard any faster speeds (i.e. stock boat) with 5 blades and the 4 blades are easier on the drives and I've had no drive issues.

I took a quick last run of the season and clicked off 80@5100rpm. This was with less than 1/2 tank of fuel in 1' chop. Again here is my specs. 500EFI's, std 1.5 Bravos, std 30" Bravo 4 blades.
I'm thinking 2 mph with less fuel and more time to trim it out.
Not to mention the original plug wires from 1Q/99...

Noticed my HPs have the original Mercruiser wires from 1995. I would like to change them out to the long style plug wires, with the GIL exhaust it is a pain to reach the 90 degree style wires. Sounds like she is pretty strong hitting 80

Yes I'm happy with it.
Maybe a set from Jegs or Summit racing will suit you.

These are some pretty strong numbers I'm reading. I've always been a fan of the 353s but never paid much attention to their performance numbers. Per BoatTest 525s in them is an 80mph boat, so 500s hitting 79-80 puts a smile on my face as I'm seeing more and more 353s on the market with 500s. I'm even reading that the 496s are a 73-75 MPH boat.

Boat Test was off with the 525 #s a properly set-up 353 will run 83-85 MPH real numbers.

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