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gwpowell
03-11-2008, 05:29 AM
We have a 07 197 with a MCX CAT and 4 blade prop. We also have a 08 X7 with the same motor and a 3 blade prop. The 197 pulls one barefooter and 3 in the boat at max speed of 41MPH at 4800RPM. The X7 pulls one barefooter and 3 in the boat at max speed of 41MPH at 4500RPM. IS 41MPH the max we can expect? Is it possible to increase speed without working the motor? and if so how?

2RLAKE
03-11-2008, 06:59 AM
I'm working on a similar situation with my '08 X14 ... Bill Weeks at Acme prop is great at working with you ... he might be able to get you another couple mph ... bweeks@acmemarine.com or 888 661 2263

EJ OJPROP
03-11-2008, 07:56 AM
We have a few new propellers in the works for this application. More MPH with a footer and the smaller motor is a tough chore. A gain of 1-2 without a footer may be achieved but you will lose some with the load of the footer. The low RPM indicates the strain from the footer.

Eric
eric@ojprops.com
800-359-9730

Jim@BAWS
03-11-2008, 08:30 AM
We have a few new propellers in the works for this application. More MPH with a footer and the smaller motor is a tough chore. A gain of 1-2 without a footer may be achieved but you will lose some with the load of the footer. The low RPM indicates the strain from the footer.

Eric
eric@ojprops.com
800-359-9730


Eric at OJ knows his stuff. Always very very easy to work with. Eric is the vendor for MasterCraft so you will find that he has your best interests at hand !

Jim@BAWS

MYMC
03-11-2008, 10:23 AM
Take the baffles out of the exhaust tips and have Eric @ OJ cut you another prop...I've been done this road several times. If the boat is too loud bolt in a pair of the old "Silent Master" mufflers.

Seaworld
03-11-2008, 10:26 AM
I had the same problems with my 2007 MCX on my X7. The acme prop will give you about 2-3 more MPH and a better hole shot. The bigger problem is making the MCX turn a few more rpms. I have heard that running Royal Purple synthetic engine oil can increase your rpms by 100. As soon as my 2008 is broke in it will get Royal Purple in it. I went to a LY6 in my new 197 and it will run 50mph with the Acme Prop. Are you running a slot or a 1:1 tranny?

H20skeefreek
03-11-2008, 10:33 AM
I'm not sure about Indmar, but PCM says NO to synthetic, and it wil void your warranty.

Seaworld
03-11-2008, 10:36 AM
I will have to double check my manual, but I think it says synthetic can be used after 100hrs.

EJ OJPROP
03-11-2008, 10:38 AM
Seaworld - What was the difference in the sizes of props, OJ to Acme?

TRBenj
03-11-2008, 11:00 AM
I'm not sure about Indmar, but PCM says NO to synthetic, and it wil void your warranty.
That is not true. For the new PCM's, they specifically say that they dont recommend synthetic, and using it does not extend the change intervals. However, if used and changed on the standard intervals, it does not void the warranty.

MYMC
03-11-2008, 11:03 AM
Until someone can back up the "data" that they are claiming lets just call it rumor or hearsay...I'd like to see radar gun or GPS proof of all these "50 mph" ski boats running around.

EJ OJPROP
03-11-2008, 11:14 AM
Mike...I was searching for a way to put it, well done. Claims of 2-3 MPH gains as well as better low end are...well...you know. A 50 MPH 197/X7 is more of a 5-6 MPH gain, but who's counting.

oldriver
03-11-2008, 11:37 AM
Eric can you help me lower my rpm's ,LT1 with powerslot,
Dont need all the high rpms,just burning more gas?

Seaworld
03-11-2008, 11:39 AM
The prop that I was using on my 1:1 in 2007 was the 13x12 Acme 3 blade. It gave me 2-3 mph over the stock OJ 4 blade.

Seaworld
03-11-2008, 11:43 AM
The 2-3 mph gain was on my 2007 x7. It did not run 50mph. My 2008 has the LY6 in it. It runs 50 with the Acme. Only ran 46 with the OJ on the 2008 LY6.

EJ OJPROP
03-11-2008, 11:47 AM
Oldriver - I can add some cup to your current propeller to drop RPM. Just send it in and let me know the current RPM to MPH.

Seaworld - 3 blades will run faster than 4 blades. So an increase in speed is no surprise or revelation. The problem with saying this prop is better than that prop, regardless of who made it, is it is rarely an apples to apples comparison. An equal test of like sizes would reveal less of a gap in numbers.

EJ OJPROP
03-11-2008, 11:48 AM
What was the prop on the LY 6?

Seaworld
03-11-2008, 11:50 AM
Eric, I am very aware of my claim about better top end and hole shot. Maybe you should get an Acme an run it for yourself before you say that I am a little crazy. I have spent the last month testing props for the 2008, and I have yet to find an OJ that will put up a fight against the Acme. Mastercraft sends a 13x12 3 blade on a 400hp powerslot. Makes the boat a rocket out of the hole but who wants to slalom at 4280rps at 36mph.

MYMC
03-11-2008, 12:04 PM
Eric, I am very aware of my claim about better top end and hole shot. Maybe you should get an Acme an run it for yourself before you say that I am a little crazy. I have spent the last month testing props for the 2008, and I have yet to find an OJ that will put up a fight against the Acme. Mastercraft sends a 13x12 3 blade on a 400hp powerslot. Makes the boat a rocket out of the hole but who wants to slalom at 4280rps at 36mph.
Testing? That would imply actual data...before you call out a supplier that has gone above and beyond for members of this board as well as the company that owns this board I would suggest you publish the "data" or at least include it when you are bashing the product.

BTW, MasterCraft specs the props installed on each and every boat...NOT OJ. Yes, Eric has input but the final decision rests with MC. If you must blame someone try putting it where it belongs.

I have tested and published everything you are claiming and can back up my results. This includes paying for (out of my own pocket) fluid dynamic studies by an independent engineer (PHD in fluid dynamics)...I've done my homework.

EJ OJPROP
03-11-2008, 12:12 PM
Seaworld - Not sure where I said you were crazy. It is not my intent to get into a war of words here. Your comment is why I do not post much. I try an offer opinions based on over 20 years of designing, building and testing propellers for tournament boats. I have in fact run many of the other propellers against ours and my OJ's fight very well thank you.

We too are testing new propellers, as I said, for this application and will have some new parts ready in a few weeks.

Seaworld
03-11-2008, 01:09 PM
Data

Mastercraft 197 MCX 1:1
OJ 12.5X12 4 blade WOT 40mph
Acme 13x12 3 blade WOT 43mph

Mastercraft 197 MCX 1.26:1
OJ 13.7x15 4 blade WOT 4970 @ 44mph
Acme 13.25X15 3blade WOT 5270 @ 46.5

Mastercraft 197 Ly6 1.22:1
OJ 13x12 3 blade WOT 5500 @ 45.6mph
OJ 14.25x14 4 blade WOT @ 46mph
Acme 13.25X15 3 blade WOT 5570 @ 48mph
Acme 13.5x15.5 3 blade WOT 5360 @ 49.8mph

This is the data that I just finished up. The hole shot always seemed better with the acme props, but one will have to decide that for themselves. Best of luck to you.

EJ OJPROP
03-11-2008, 01:45 PM
Numbers from last test;

197 LY-6 Numbers are an average not peak radar speeds of a min of 3 runs in different directions. Acceleration numbers obtained from Stalker program to determine actual acceleration comparission.

14.25 X 14 LC 0-36 in feet --169.003 46.6 MPH at 5140 RPM

New 3-Blade Version 1 -- 0-36 in feet 126.9 47.7 MPH at 5600 RPM

36 MPH @ 3900 RPM.

I would venture to guess actual acceleration numbers from the props you tested may surprise you. We work very hard to build propellers that work well on both ends but we lean more towards the low end power. I am still in the process of making a few changes to the above 3-blade and will post those results as we complete testing.

H20skeefreek
03-12-2008, 07:39 AM
That is not true. For the new PCM's, they specifically say that they dont recommend synthetic, and using it does not extend the change intervals. However, if used and changed on the standard intervals, it does not void the warranty.
Ok, I haven't actually read the manual....now I do see the owner of PCM on a regular basis (every few weeks), and I thought that was what he said, but anyway, they definately say there is no advantage.

H20skeefreek
03-12-2008, 07:39 AM
Ok, I haven't actually read the manual....now I do see the owner of PCM on a regular basis (every few weeks), and I thought that was what he said, but anyway, they definately say there is no advantage.

H20skeefreek
03-12-2008, 09:44 AM
Eric,

I have an '85 with Powerslot, and I am not concerned about top speed. As long as I can run 36, I don't care. My hole shot is phenomenal. I'd like to reduce fuel consumption, would cupping this prop help? How can I tell if it already has a cup? There seems to me a little, but not much. I'm swinging a 14x18 Legend, but don't want to drop the coin on another prop at this time.

MYMC
03-12-2008, 10:17 AM
This is the data that I just finished up. The hole shot always seemed better with the acme props, but one will have to decide that for themselves. Best of luck to you.
Seemed? The words "data" and "seemed"? Where is the time over distance? What version of the Stalker software are you running?

Just a sample of what must be considered:
Weather? Water temp? Tower equipped? Bimini? How much fuel and what octane? Was each subsequent test conducted under the same weight and fuel loads? Blower running? How many passes per test? How many directions were the runs conducted in? All tests accomplished same day with no change in temp or humidity?

EJ OJPROP
03-12-2008, 10:35 AM
H2O - What is the RPM at 36? We can reduce RPM up to about 400 with additional cupping.

6ballsisall
03-12-2008, 10:38 AM
If you put an Edelbrock sticker on the transom of the boat you'll gain 50HP and 10 MPH. 8p 8p

TMCNo1
03-12-2008, 10:43 AM
If a F-15 can fly with 1 wing, http://www.tmcowners.com/teamtalk/showthread.php?t=22016, then I figure I can get my boat to run 100 MPH! I'm just sayin'!

H20skeefreek
03-12-2008, 03:09 PM
H2O - What is the RPM at 36? We can reduce RPM up to about 400 with additional cupping.
Eric,

I don't remember the RPM, I'll have the boat back on the water in a few weeks. I think it's around 3750??? I'll double check then. Lowering RPM by 400, increases top end speed and lowers hole shot right? How much hole shot (I know, hard to qauntify) do you think I'd lose? I do have a short setup at one end, but we aren't gunning it to get up to speed, so there is a little gas to work with.

H20skeefreek
03-12-2008, 03:12 PM
If you put an Edelbrock sticker on the transom of the boat you'll gain 50HP and 10 MPH. 8p 8p
I already replaced the r's in Master Craft with big R's, that helps right?

MasteRCRaft!

JLeuck64
03-12-2008, 03:57 PM
Seaworld - Not sure where I said you were crazy. It is not my intent to get into a war of words here. Your comment is why I do not post much. I try an offer opinions based on over 20 years of designing, building and testing propellers for tournament boats. I have in fact run many of the other propellers against ours and my OJ's fight very well thank you.

We too are testing new propellers, as I said, for this application and will have some new parts ready in a few weeks.

I would put more faith in your limited number of posts considering your experience...

Please keep posting and just ignore the armchair prop testers out their!!!

Oh, and by the way I love the performance of my new stock OJ prop that I installed after last years little accident I had!

EJ OJPROP
03-12-2008, 04:01 PM
Eric,

I don't remember the RPM, I'll have the boat back on the water in a few weeks. I think it's around 3750??? I'll double check then. Lowering RPM by 400, increases top end speed and lowers hole shot right? How much hole shot (I know, hard to qauntify) do you think I'd lose? I do have a short setup at one end, but we aren't gunning it to get up to speed, so there is a little gas to work with.


I would like to see the RPM closer to 1:1 3600 @ 36 or a hair under, should provide a softer pull as well allowing you to work the boat some. The reduction in RPM should not change the speed much if any and may improve low end a bit.

gwpowell
03-12-2008, 04:53 PM
For those of you watching this thread and wanting more speed. I posted another thread relating to the new exhaust tips which are noisy. It seems modification to these tips can improve engine efficiency and therefore increase speed. See 'New Noisy Exhaust Tips"
http://www.tmcowners.com/teamtalk/showthread.php?t=21980
Mike has been a great help.

6ballsisall
03-12-2008, 05:14 PM
I already replaced the r's in Master Craft with big R's, that helps right?

MasteRCRaft!


Absolutely! Thats at least 15HP and 4 mph! Now if you just put a Jegs sticker on the windshield and a NOS sticker on your engine cover you'll gain an extra 100hp no problem. 8p 8p

Danimal
03-12-2008, 05:47 PM
Absolutely! Thats at least 15HP and 4 mph! Now if you just put a Jegs sticker on the windshield and a NOS sticker on your engine cover you'll gain an extra 100hp no problem. 8p 8p

Let's not forget the Hooker Headers decal in the window. That would surely get you more speed!!:D

http://www.cartype.com/images/page/hooker_headers.jpg

EJ OJPROP
03-13-2008, 06:45 AM
I would put more faith in your limited number of posts considering your experience...

Please keep posting and just ignore the armchair prop testers out their!!!

Oh, and by the way I love the performance of my new stock OJ prop that I installed after last years little accident I had!


I will be here and chime in when I can. Good to hear the "stock" prop worked well for you (erk?) and thank you for your support.

Diesel
03-13-2008, 10:18 AM
I will be here and chime in when I can. Good to hear the "stock" prop worked well for you (erk?) and thank you for your support.

When will the new three blade be available? I would like to see some better performance out of my PS209 with MCX.

EJ OJPROP
03-13-2008, 10:24 AM
The new props should be available by the end of April.