First cleaned up pictures of my new Prostar - Page 5

jeff shelton · #41 01-23-2013, 12:39 PM

Quote:

Originally Posted by Cloaked

Go-to is a 13x13 LH for the 454 regardless of the gearing ratio. There are other possibilities. Keep it simple and functional. Don't worry about making Jeff Foxworthy proud.

As was stated, if you want to know the current 4 banger, pull the prop and look on the hub.

My 1990 190 with powerslot trans has a ACME 4blade 14x20. Top Speed right at 50mph. I'm not sure what would have been installed from the factory.
I do have an additional 3 blade that came with the boat but I'm not sure of the size. The dealer that I boat the boat from said that they installed the new 4 blade because the boat was turning 5600rpms with the 3 blade. I have yet to run the prop to confirm rpms and speed.

TRBenj · #42 01-23-2013, 01:43 PM

Quote:

Originally Posted by jeff shelton

My 1990 190 with powerslot trans has a ACME 4blade 14x20. Top Speed right at 50mph. I'm not sure what would have been installed from the factory.
I do have an additional 3 blade that came with the boat but I'm not sure of the size. The dealer that I boat the boat from said that they installed the new 4 blade because the boat was turning 5600rpms with the 3 blade. I have yet to run the prop to confirm rpms and speed.

Those numbers make sense. The 13x14 Acmes work well on the 1:1 big blocks. Multiply that 14" of pitch by your 1.5 reduction and youre at 21"... so 20" isnt too far off. How many RPM's do you pull that prop? My guess is 4600 +/-? 50mph seems about right for a 330hp BBC in a 19' ski boat. Thats where most of the 454 Barefoot Nautiques and Ski Nautiques run.

5600rpm would imply that the other prop was a pretty gross mismatch for your powertrain. Probably in the 13x14 to 13x16 range? Either that or the 5600rpm claim is likely incorrect.

jeff shelton · #43 01-23-2013, 03:33 PM

Quote:

Originally Posted by TRBenj

Those numbers make sense. The 13x14 Acmes work well on the 1:1 big blocks. Multiply that 14" of pitch by your 1.5 reduction and youre at 21"... so 20" isnt too far off. How many RPM's do you pull that prop? My guess is 4600 +/-? 50mph seems about right for a 330hp BBC in a 19' ski boat. Thats where most of the 454 Barefoot Nautiques and Ski Nautiques run.

5600rpm would imply that the other prop was a pretty gross mismatch for your powertrain. Probably in the 13x14 to 13x16 range? Either that or the 5600rpm claim is likely incorrect.

I didn't not mention previously but it does have the 454 with slot. You are correct on rpms. They are right at 4600rpms.
I had planned to put the other prop on before the end of this past summer to see what the rpms and speed were but just didn't get to it. I do think it is a 19 or 20.

TRBenj · #44 01-23-2013, 05:22 PM

Quote:

Originally Posted by jeff shelton

I didn't not mention previously but it does have the 454 with slot. You are correct on rpms. They are right at 4600rpms.
I had planned to put the other prop on before the end of this past summer to see what the rpms and speed were but just didn't get to it. I do think it is a 19 or 20.

Probably a hand finished prop (Federal maybe)? If so, then add 200 or so RPM for the different style if the same pitch... if less pitch, add another 150-200rpm per inch. If its a 19" and turns more than 5k RPM then its probably flexy (ie, worn out). Ive seen that a few times.