Pirata/ Saltare info

[scbowles]

Hey guys I recently acquired a 1991 pirata needed a bunch of work etc. Installed reman 454 gen V added Edelbrock marine intake manifold . TBI conversion from performance fuel Injection and did a little port matching. also reman trans rudder from Discount inboard marine, fresh air exhaust. plus several other items. I have 2 props both Acme 3 blade 13/13 and 4 blade 14/12. fuel economy and performance with 3 blade 13/13 sucks. prop slips horribly. with 4 blade 14/12 excellent fuel economy and performance, untill reaching speed close to 40 mph . end up with top speed of 40 mph. with engine speed of 4400.what other wise 24 mph 2200 rpm with good accell. with 3 blade 13 inch 24 mph over 3000 rpm s accell not good. what are you guys seeing with your boats.

[korey]

The prop specs thread has several Saltares in it, so you might check out that sticky:
https://forum.supraboats.com/showthread.php?15325-Prop-Specs-ONLY

If your slipping with a 13x13, you may have something funny going on. What is the gap between your strut and the back side of the prop? This should be less than 1", on mine it's more like 1/8". That dimension isn't actually what's important, but indirectly affects what is important to prop efficiency - distance from hull. You're not going to get a lot more than 40 MPH out of these boats no matter what you do.

I've personally run these two props on my '86 Saltare with 454 - which is probably not as healthy as your freshly built engine:
ACME 209 4 Blade 13" x 12.5" 0.080 cup: WOT unloaded: 4500RPM at 37.5MPH (ridesteady digital readout, GPS). 11.2MPH at ~2600RPM with ~1900lb ballast and wake sharper for surfing. Seems like it's working pretty hard, nearly not doable with more than 3 extra bodies onboard. No chance in the world of getting on plane with that weight.

Acme 1229 13x11" 0.080" cup 3 blade. WOT Unloaded: 4600RPM at 41.0MPH. Yes, it sped up and only turns 100 more R's than my old 209. I don't quite understand it, but it's true! The boat is "throw you out of the observer's seat" fast out of the hole now. Seems to cruise pretty happily unloaded at 2600RPM at 25-26MPH. Fuel consumption makes it seem like it's not in the secondaries of the carb, therefore still fairly economical.

With mixed use, i run about 10GPH, or a little better.

Also, how are you measuring speeds? if it's from the stock speedometers, have you calibrated to GPS or the old school timing method? If not, throw your readings away.

[cadunkle]

I currently run an Acme 431 13x13 CNC 3 blade on my Saltare with 454 and Velvet Drive 1:1 trans. 22 MPH at maybe 2300-2400 RPM. Top speed is mid-high 40s, I forget. Fuel consumption around 6-7 GPH at 22 MPH. If you have the same prop I do something is way off with it, maybe been reworked to a really low pitch or damaged and cut down to smaller diameter. This 13x13 gives me about 150 RPM less at any given MPH than the Acme 13x12 CNC 3 blade I used to run. Less slip than the original cast 14x13 3 blade, but lower top end. The cast 14x13 would do 50-51 MPH but did not perform as well down low.

[scbowles]

thanks guys I am using dual gps speedo's most recent test is with Acme 4 blade 14 x 12 #3033 .60 cup.
2000 rpm 17 mph
2200 rpm 24 mph
2800 30
3000 32
3400 34
3600 37
4200 41