QuickSilver Nemesis 4-Blade 19P, Nice Prop

[TwoBallScrewBall]

Quick review of the Nemesis 4 blade aluminum prop I just put on my 20ft 1988 Bowrider.

Installed last weekend and ran for the first time.

Boat had a 3 blade 14.5X21 that kept the top end a little bit lower than I liked. Was tough to get 4200 with a couple people in the boat. OMC 5.0 (HO I think).

I vented that prop (drilled the hub for bubbles) which helped a lot with holeshot when we were running heavy, but top end was still too low of course.

Went to the 19P Nemesis since they claim the props are designed to match the RPM characteristics of a 3 blade.

Holeshot is really good, pushes you back and jumps up on plane in a couple seconds, especially when the boat is light. Would easily raise a skiier. WOT with an average load I can spin 4500 and the engine feels like it's working less at all RPMs. 2800 on plane is 25mph on GPS, real nice cruise. Measured MPG (GPS Trip / Gallons) is up from 2.1 to 2.4. Top end at 1000ft elevation (freshwater obviously) is 41mpg GPS. I saw 42 once it was the wind This puts my slip numbers pretty high so I am going to verify my gearcase ratio. It's 31 years old and I know it's been repowered at least once.

Excellent prop. The only other 4 blade I have experience with is the Mercury Revolution SS. Had one on my two previous boats and they are phenomenal. This one is right on par for 20% of the price. And I boat in the mountains so I want to run aluminum in case I misjudge a shoreline point

 

[dingbat]

WOT with an average load I can spin 4500 and the engine feels like it's working less at all RPMs. 2800 on plane is 25mph on GPS, real nice cruise. Measured MPG (GPS Trip / Gallons) is up from 2.1 to 2.4. Top end at 1000ft elevation (freshwater obviously) is 41mpg GPS.

interesting...how did you come up with the mpg numbers?
I would have thought you would get much better performance

 

[TwoBallScrewBall]

I fill it. I keep a trip odometer on the GPS app on my phone when we're on the boat, then I re-fill it and take the miles on the trip divided by the gallons used. I've put 55 miles on it so far and used 22.4 gallons of gas.

 

[TwoBallScrewBall]

Much better performance than what? The top end or the mpg?

 

[mfelthousen]

Might have been wondering about the mixing up of mpg and mph terms in the posts.

 

[Stinnett21]

I've been seriously considering one of these myself. My boat is very similar to yours. Currently getting good performance out of a 19" Vengeance but like everyone hoping for more. Hard to justify and convince the wife we need to spend $700 for a good Mercury prop on already good running boat. I was thinking the Spitfire/Nemesis is more or less an aluminum version of the Rev 4. If I tear one up I could buy three more. Thanks for posting your results.

 

[dingbat]

Much better performance than what? The top end or the mpg?

Both actually.

My boat is 2’ longer and weighs #5400. Runs 31 mph cruise, 41 mph WOT and gets ~ 2.2 mpg measured with fuel flow sensor.

I would have thought a smaller, lighter boat would have bettered both figures

 

[Cortes100]

I've been running the Nemesis 4-Blade 21P and happy with the performance. It will tag the rev limiter with a light load. Also have the same in a 19P, which I used a few times but quickly hits the limiter. I was keeping it for a loaded up day, but have yet to have one of those.
The 21P pulls very good though out the range, WOT easily hit 45 mph. A nice cruise is around 32-3300 rpm @ 30 mph.
Have no reason to change it out. Could be something better, but not buying more props just to try. The Nemesis 19 and 21 were around $150 at my dealer. The Merc Spitfire was a few bucks more.
Boat has an alpha drive 1:81 and we're at 3000' for elevation.

 

[TwoBallScrewBall]

Both actually.

My boat is 2’ longer and weighs #5400. Runs 31 mph cruise, 41 mph WOT and gets ~ 2.2 mpg measured with fuel flow sensor.

I would have thought a smaller, lighter boat would have bettered both figures

What kind of boat? HP? I'm in a 31 year old bow rider that I haven't weighed, running a used GM 305 that was swapped in by the previous owner. I'm assuming I'm around 200-220hp. I'm 10% above your mpg, and there's a hydrofoil on my out drive that I'm pulling off this week so we can see what that does to top end speed.

I'm very happy with it, not much else matters.

 

[Starcraft5834]

nice, Im a firm believer in 4 blade being the best over all choice.... heavy boats simply perform better with one...if you dont mind losing a few mph... best choice overall

 

[Gary GAS]

I have the spitfire/ nemesis 21 pitch 4 blade on my 2008 19 ft.bluewater open bow with the volvo 4.3 gl and I did,nt lose any top speed over the same. pitch 3 blade. It planes faster and has a two mph higher cruise speed at the same rpm and tops out at 4860 rpm,s at 47 mph gps.This is the best prop I have found and I have tried many alum and s.s. best prop for the money out there by far.

 

[TwoBallScrewBall]

Pulled the hydrofoil off my out drive this weekend (was on there when I bought the boat)

Cruise speed at 3000rpm went from 25 to 27. Wot max speed trimmed out went from 41 to 43. No difference in handling without it. Definitely leaving it off.

I expect average mpg to increase a little, but I forgot to run my GPS for a few trips this tank so that will have to wait until next tank.

 

[TwoBallScrewBall]

Update after about 120 miles on the prop. All in a lake at 1150ft, in a 31 year old Rinker 20.5ft bowrider with a Cobra 305.

Love the prop. Wanders less at idle around the docks. Pulls like a tractor even with a full tank and 900lbs of people and gear. Pops up on plane in 3-4 seconds fully loaded up, no crazy bow rise. Consistent 42-43 top end but I only spot check that here and there, being nice to this old engine. Thankful its running as well as it is. In a sloppy chop (think washing machine, holiday weekend, bozos everywhere) she will plug along on plane with the drive tucked in at 2700rpm, about 22 mph, and just slices thru the mess. Clean water, it pulls nice cruises at 27mph/3000rpm or 33mph/3500rpm. Calculated mpg (GPS trip vs gallons taken) is now 2.9mpg. Up from 2.4 last time I checked. Some of that is me getting to know the boat and feel where its sweet spots are. A lot is the prop. Boat just feels like it's not working as hard as it was.

Hope this helps someone else.