Acme 537 vs 1941

[TipoFloe]

Hello everyone,

I found a few references but did not find enough information to make a decision so here it goes.  

I have a 2007 VLX Silver Edition with Hammerhead 383 (6.2L 400HP) engine.  Recently my OEM prop was damaged and I had it repaired but the prop was repaired poorly and it lost the initial "kick"(holeshot) that it had before the accident.  

The boat has 1,250lbs of factory ballast and comes with Power Wedge Gen1, adding another 1,000lbs of "weight" for bigger wakes.  I did not have any issues before the accident getting the boat to 18MPH to 24MPH with the ballasts full and the wedge down and with up to 10 male adults on the boat.

I am thinking of replacing it with a brand new OEM prop (Acme 537 13.5 x 16"), but I was recommended to upgrade to Acme 1941 14.5 x 15.5 as I am told that this would be a better match for the engine and the way I use the boat.  The main reason behind this is because the 537 prop is an older prop that was not made specifically for wakeboarding, but for overall speeding (in other words, the props were less efficient in 2007 vs today's props?).  

Has anyone replaced their OEM prop to 1941?  If so, what did you think of the replacement and how was the performance after the upgrade?

Thanks for your input!

Edited September 22, 2016 by TipoFloe

[minnmarker]

537 to 1235.  Very happy with 1235 loaded performance and only lost about 4 mph top speed.
That said, 537 is a better prop for cruising and skiing.  Others will suggest even lower pitch props.

For future repairs http://www.propmd.com/

They are really good at repairs and have the best prices for new props.

[Nitrousbird]

First, see the Acme prop guide I put together:

You are running very little weight for that hull so it is no surprise you don't have an issue with your old prop.  The 537 is a 13.5" diameter prop.  Even for those trying to get high speed runs, skiing, footing, etc. I feel a 13.5" prop is too small of a diameter on these hulls...14" should be the minimum.  The equivalent performing 14" would be the 1939 (the 1939 outperforms the 537 in every way...they shouldn't even sell the 537 anymore IMO). 

In a 14.5" prop, the 1941 would probably perform in a similar manner.  Less prop slip being a bigger diameter, which would make up the difference for being a little less aggressive prop.  2701 would likely be a more even match.  1273 would also be a great match to get you a bit more pulling power without losing much top end (it is basically the vanilla 1235 that used to be the popular "power prop" with more cup).

15" is the thing now.  For your current use, a 2247 would be a good match.  I am guessing you aren't doing any surfing based on you running stock ballast.  If you plan to do that or up your stock wakeboard wake, I'd recommend the 2773.

As for vendors selling props, I would take Wakemakers over Prop MD that was mentioned above.  Wakemakers has a big selection, supports TMC AND has much better prices. 

 

[oldjeep]

fwiw, blue sea yacht and nettles both beat wakemakers on price when I was buying my spare 1939 and  Acme puller kit. Propmd is 3 miles away from me and had very close pricing at the time but didn't have one on the shelf. Hands down the only place I would go for repairs, propmd fixed a 1939 that I completely mangled.

Edited September 23, 2016 by oldjeep

[1HELLUVALIFE]

Nettles has great customer service and prices. 

 

[blk93jeepzj]

I have a used 537 off my boat if you are interested in it?  In good shape just don't need 2 spare props laying around.  PM me if interested.

[MJR63]

I have a line on a used 1235.  PM me if you are interested.

[TipoFloe]

On 9/23/2016 at 3:12 AM, Nitrousbird said:

First, see the Acme prop guide I put together:

You are running very little weight for that hull so it is no surprise you don't have an issue with your old prop.  The 537 is a 13.5" diameter prop.  Even for those trying to get high speed runs, skiing, footing, etc. I feel a 13.5" prop is too small of a diameter on these hulls...14" should be the minimum.  The equivalent performing 14" would be the 1939 (the 1939 outperforms the 537 in every way...they shouldn't even sell the 537 anymore IMO). 

In a 14.5" prop, the 1941 would probably perform in a similar manner.  Less prop slip being a bigger diameter, which would make up the difference for being a little less aggressive prop.  2701 would likely be a more even match.  1273 would also be a great match to get you a bit more pulling power without losing much top end (it is basically the vanilla 1235 that used to be the popular "power prop" with more cup).

15" is the thing now.  For your current use, a 2247 would be a good match.  I am guessing you aren't doing any surfing based on you running stock ballast.  If you plan to do that or up your stock wakeboard wake, I'd recommend the 2773.

As for vendors selling props, I would take Wakemakers over Prop MD that was mentioned above.  Wakemakers has a big selection, supports TMC AND has much better prices. 

 

I always felt that the stock ballast was inadequate and now that I'm getting into wakesurfing, I'm thinking of adding at least another 500lbs of ballast at the aft of the boat as well as the center...  Having said this, the list of prop models you suggested here is confusing me even more...  

Since the 15" is the thing now, I am very much interested in the 2247.  My questions related to these 15" props would be:

How would the 2247 or 2773 affect the overall RPM and the top speed of the boat?  What about fuel efficiency...?  From the specs I gather that 2247 = more top speed and 2273 = more holeshot/torque when taking off?

Wakemakers recommends 1941 for general use, 1235 (or 1273 per your recommendation) and finally 2079 for heavily ballasted boats...  

I guess for the time being I will have to check with my mechanic if the 15" will fit on my boat and then I'll have to decide between 2247 or 2773 (if I'm going to be upgrading the ballast as you suggest).  

Thanks for the info!

On 9/23/2016 at 6:56 AM, blk93jeepzj said:

I have a used 537 off my boat if you are interested in it?  In good shape just don't need 2 spare props laying around.  PM me if interested.

Thanks for the offer, but based on the consensus I think I'll be permanently upgrading to a bigger prop!

On 9/23/2016 at 9:48 AM, MJR63 said:

I have a line on a used 1235.  PM me if you are interested.

Hello!

Thanks for the offer.  I am interested.  But let me check if my boat can fit a 15" and if not I'll PM you!

Edited September 24, 2016 by TipoFloe

[MJR63]

15 minutes ago, TipoFloe said:

I always felt that the stock ballast was inadequate and now that I'm getting into wakesurfing, I'm thinking of adding at least another 500lbs of ballast at the aft of the boat as well as the center...  Having said this, the list of prop models you suggested here is confusing me even more...  

Since the 15" is the thing now, I am very much interested in the 2247.  My questions related to these 15" props would be:

How would the 2247 or 2273 affect the overall RPM and the top speed of the boat?  What about fuel efficiency...?  From the specs I gather that 2247 = more top speed and 2273 = more holeshot/torque when taking off?

Wakemakers recommends 1941 for general use, 1235 (or 1273 per your recommendation) and finally 2079 for heavily ballasted boats...  

I guess for the time being I will have to check with my mechanic if the 15" will fit on my boat and then I'll have to decide between 2247 or 2273 (if I'm going to be upgrading the ballast as you suggest).  

Thanks for the info!

Thanks for the offer, but based on the consensus I think I'll be permanently upgrading to a bigger prop!

Hello!

Thanks for the offer.  I am interested.  But let me check if my boat can fit a 15" and if not I'll PM you!

What motor do you have?  Acme doesn't recommend a 15" prop unless you have the HP to back it up.  A 15" prop requires a lot of HP to push it....

[teamerickson]

1235 is a 14.5 diameter prop. 

[MJR63]

18 minutes ago, teamerickson said:

1235 is a 14.5 diameter prop. 

Yes, I know that...I was commenting on his consideration of the 2247 or 2273 props....

[Nitrousbird]

10 hours ago, TipoFloe said:

I always felt that the stock ballast was inadequate and now that I'm getting into wakesurfing, I'm thinking of adding at least another 500lbs of ballast at the aft of the boat as well as the center...  Having said this, the list of prop models you suggested here is confusing me even more...  

How would the 2247 or 2273 affect the overall RPM and the top speed of the boat?  What about fuel efficiency...?  From the specs I gather that 2247 = more top speed and 2273 = more holeshot/torque when taking off?

Wakemakers recommends 1941 for general use, 1235 (or 1273 per your recommendation) and finally 2079 for heavily ballasted boats...  

I guess for the time being I will have to check with my mechanic if the 15" will fit on my boat and then I'll have to decide between 2247 or 2273 (if I'm going to be upgrading the ballast as you suggest).  

2247 will likely have a similar top speed.  Never heard of a 2273.  If you mean a 2773, that will for sure have more hole shot but you will lose top speed.  I run the 2773 on my boat and love it.

No need to check with your mechanic, the 15" prop will fit.  I don't believe Malibu has ever sold a V-drive boat that a 15" prop won't fit on with proper clearance.

You need more weight for sure, especially if wake surfing.  I have a smaller hull and run almost 3x the weight you are running total.

If you want to save money, go snag a USED 1235.  They are super common and listed all the time - just low ball someone and you will end up scoring one over the winter cheap.  It used to be the "go to" prop until the 15" props arrived.  I still think the 1273 is a better match than the 1235 for most users (same prop with more cup). 

[TipoFloe]

17 hours ago, MJR63 said:

What motor do you have?  Acme doesn't recommend a 15" prop unless you have the HP to back it up.  A 15" prop requires a lot of HP to push it....

I have an Indmar Hammerhead 383, 6.2L @ 400 HP.

Edited September 24, 2016 by TipoFloe

[TipoFloe]

7 hours ago, Nitrousbird said:

2247 will likely have a similar top speed.  Never heard of a 2273.  If you mean a 2773, that will for sure have more hole shot but you will lose top speed.  I run the 2773 on my boat and love it.

No need to check with your mechanic, the 15" prop will fit.  I don't believe Malibu has ever sold a V-drive boat that a 15" prop won't fit on with proper clearance.

You need more weight for sure, especially if wake surfing.  I have a smaller hull and run almost 3x the weight you are running total.

If you want to save money, go snag a USED 1235.  They are super common and listed all the time - just low ball someone and you will end up scoring one over the winter cheap.  It used to be the "go to" prop until the 15" props arrived.  I still think the 1273 is a better match than the 1235 for most users (same prop with more cup). 

Yup I meant 2773.  :D

I've been on the phone with a local prop dealer and he was the one that originally recommended 1941 over the 537.  But I wanted some feedback from the folks here and I am getting exactly the information I wanted from everyone!  :D

[Bill_AirJunky]

Digging up a month old thread. The lake is getting low & I tried using my 537 as a depth gauge... found the bottom. It's been reworked, looks great, and hoping to go out for a test ride on Sunday. I looked around at the marina & found a 1939. Thinking that I might ask the boss if I can take it for a test spin before I commit to it. Might be interesting to compare the two props side by side. And keeping in mind that I ride considerably faster than most wakeboarders, how it performs at 26 mph, much less top speed. Not really sure what I'm hoping to gain, other than some time on the lake on what may be the last nice day out for a while. If I gain some holeshot, or maybe lower the RPMs at riding speeds, maybe I'll make it mine.

[Bill_AirJunky]

I got out for a bit yesterday & tested my reworked 537 & a new 1939. I filled the 900 lbs of stock ballast, plus I have about 300 lbs of lead & noted RPMs at 3 speeds that I thought were most important, ie; 10, 20 & 26 mph (the speed I ride at). Plus top speed. Overall the reworked 537 did great, no vibration or singing, top speed fully loaded of 42 mph with the engine hitting the rev limiter at around 5330 RPMs. The 1939 dropped the RPMs as much as 200 RPMs, and had a top speed of 43 MPH.

Another interesting finding was very little to no difference in top speed whether the ballast was loaded or not. Guess we must have reached the hull's max.

                         Acme 537                                 Acme 1939
10 mph              2450                                           2250
20 mph              2975                                           2825
26 mph              3300                                           3175
Top Speed     42 mph @ 5330 RPMs        43 MPH @ 5060 RPMs (loaded)
                                                                        43 MPH @ 5110 RPMs (unloaded)

So with the engine running less RPMs with the 1939, does it stand to reason that it should burn a bit less gas?

[MadMan]

43 minutes ago, Bill_AirJunky said:

Another interesting finding was very little to no difference in top speed whether the ballast was loaded or not. Guess we must have reached the hull's max.

                         Acme 537                                 Acme 1939
10 mph              2450                                           2250
20 mph              2975                                           2825
26 mph              3300                                           3175
Top Speed     42 mph @ 5330 RPMs        43 MPH @ 5060 RPMs (loaded)
                                                                        43 MPH @ 5110 RPMs (unloaded)

 

This is my finding too, most inboards seem to max out top speed in the low to mid 40's.  It take's significantly more horsepower to make into the 50's.  This is because the prop is angled down and you can't trim it up like an outboard or I/O.