Complete repowering of a brick
#282
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From: KY
#284
#286
Sure is taking a while to get a response from OSO on a reply. I'm starting to look into pulling the motor and getting another dyno done. I just cannot get past the thought of adding 120 HP and gain nothing. Yes I have better hole shot, but for years my motor was running rich and the rebuild did fix it. So now it is running efficiently but I just cannot get past the extra power and no gain.
I would have had it out already if it was a 2 hour pull, but this is a 4 to 6 hour pull because I have to take a bunch of stuff off just to get it out. Don't want to want another couple years and finally get around to doing it and then if its less HP then the statement will be, it was but now its not.
Got to talk to my help and see if he is up for it, looking at to dyno shops in KY, so if it happens I'll post up
I would have had it out already if it was a 2 hour pull, but this is a 4 to 6 hour pull because I have to take a bunch of stuff off just to get it out. Don't want to want another couple years and finally get around to doing it and then if its less HP then the statement will be, it was but now its not.
Got to talk to my help and see if he is up for it, looking at to dyno shops in KY, so if it happens I'll post up
#287
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From: KY
Do you have the dyno sheet you can post? Sorry if that was addressed earlier in this thread. I still believe a set of worked 3 x 3's would be the fastest props. You also want them to be where you can turn the engine as many RPM as you can under the rev limiter at WOT and not be well beyond where HP is falling off. In most cases, RPM = speed. So let's say Eddie says your new target WOT RPM is 5,200. If you turning a set of 3 x 3's at 5,200 RPM is netting you no additional speed, then I too question what is happening here. That extra 120 HP should not be just pi$$ing away in prop slip. You're not going to see the gains other boats would at an extra 120 HP but I would have fully expected somewhere in the 2 - 4 MPH range.
I did notice the dyno sheet shows Wisconsin and my oil pressure stays at 80 psi. Asked the builder if this was correct and do I need to get a higher oil pressure gauge. Response was not reassuring and gave me pause if there was an issue. Hooked the motor up, and cold it goes above 30 at idle, and does not go above 50 no matter what, stays mostly below 50. My guess is the oil pressure gauge was shorted to stay at 80.
#288
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From: Tennessee
Here are some pics of the dyno sheets. They were run with dyno headers with all accessories except the p/s pump. I didn't want to have to plumb the p/s just for the dyno. So, those 2 items will cost a little power. I would say in the 20-25 hp range. So that makes it around 515-520 hp. We were only shooting for 500 hp, but a little extra never hurts. Bob was aware of the use of dyno headers and the lack of the p/s pump.
From what I understand, the 502 Mags make right around 425 hp. I've never had the chance to dyno a bone stock one, so I'm going on hearsay. They are all set up on the rich side as Mercury has no idea of where that engine is going or how it will be ran. That is taken into consideration with their numbers.
As it sits, there is no reason under the sun that the engine won't make 500 hp. It's a 509, 9.3:1, a pretty decent size cam, with some mild porting of both the heads and the intake. It should have no problem making 1 hp per cu in. This was never about an all out hp build. It was approached as a freshen up with a few well placed mods to mainly increase the torque, as it's a very heavy boat.
The dyno is a Stutska that is made in Wisconsin. That is why it says WI. on the top of the page under Stutska. While it's not my dyno, I have no reason in the world to doubt it's accuracy. We check the calibration with weights on a regular basis. I have no problem at all with it being put on another dyno. I'm confident in what we built.
Here are the dyno sheets for those that are interested. I'm not sure where the 80# comment came from. As you can see, the oil pressure goes up the entire pull. It's a little high because the oil is still pretty cold.
I take it very personally when a customer doubts our work or me. I'm hate that a customer is not 100% happy with what we delivered. I'm completely confident in the power that it makes, even though it doesn't show in much of a speed increase. It's pulling 2 more inches of prop to a higher rpm than the smaller props. I'm really not sure why that's not translating into speed. It gets on plane faster with the larger props than it did with the smaller ones, so it's obviously making more torque/power.
Bob, if there is something else or something more that you expected from us, then please contact me and I will do my best to accommodate it. I want everyone to be as satisfied as possible with their purchase. I'm only a phone call away. You can reach me anytime. If you would like some assistance is setting up the boat/drive height/ prop combo/whatever, I would be more than happy to help in any way that I can.
Eddie
From what I understand, the 502 Mags make right around 425 hp. I've never had the chance to dyno a bone stock one, so I'm going on hearsay. They are all set up on the rich side as Mercury has no idea of where that engine is going or how it will be ran. That is taken into consideration with their numbers.
As it sits, there is no reason under the sun that the engine won't make 500 hp. It's a 509, 9.3:1, a pretty decent size cam, with some mild porting of both the heads and the intake. It should have no problem making 1 hp per cu in. This was never about an all out hp build. It was approached as a freshen up with a few well placed mods to mainly increase the torque, as it's a very heavy boat.
The dyno is a Stutska that is made in Wisconsin. That is why it says WI. on the top of the page under Stutska. While it's not my dyno, I have no reason in the world to doubt it's accuracy. We check the calibration with weights on a regular basis. I have no problem at all with it being put on another dyno. I'm confident in what we built.
Here are the dyno sheets for those that are interested. I'm not sure where the 80# comment came from. As you can see, the oil pressure goes up the entire pull. It's a little high because the oil is still pretty cold.
I take it very personally when a customer doubts our work or me. I'm hate that a customer is not 100% happy with what we delivered. I'm completely confident in the power that it makes, even though it doesn't show in much of a speed increase. It's pulling 2 more inches of prop to a higher rpm than the smaller props. I'm really not sure why that's not translating into speed. It gets on plane faster with the larger props than it did with the smaller ones, so it's obviously making more torque/power.
Bob, if there is something else or something more that you expected from us, then please contact me and I will do my best to accommodate it. I want everyone to be as satisfied as possible with their purchase. I'm only a phone call away. You can reach me anytime. If you would like some assistance is setting up the boat/drive height/ prop combo/whatever, I would be more than happy to help in any way that I can.
Eddie
#289
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Joined: Mar 2009
Posts: 386
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From: Beaverton Or
I truly believe the hull is not lifting or planing here a hull that long and heavy is a incredible drag he actually spoke a bit on eailer saying the boat porpsied a bit indicating it was coming up and then fell off. Yes bottom paint can do that...i know many cry BS but just as many have seen nice increases with the removal of the paint or a refinish.
http://www.offshoreonly.com/forums/g...aint-slow.html
http://www.offshoreonly.com/forums/g...aint-slow.html
Last edited by Pliant; 10-06-2015 at 01:13 PM.
#290
I truly believe the hull is not lifting or planing here a hull that long and heavy is a incredible drag he actually spoke a bit on eailer saying the boat porpsied a bit indicating it was coming up and then fell off. Yes bottom paint can do that...i know many cry BS but just as many have seen nice increases with the removal of the paint or a refinish.





