LS Build: In Progress
03-19-2019, 07:09 AM
#171
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Nice numbers.
I personally will not build high RPM boat engines again. To achieve my PK HP and speed I was spinning my engines ~6500 RPM that pushed my "legit" cruise speed to 5000 RPM's. There was never a real balance in prop pitch selection. Either spin the s#it out of them with a small wheel or load the engines with a bigger prop. Engines ran great, but running engines 6000+RPM's for miles that you hand built with your hard earned money just makes your guts pucker.
I personally will not build high RPM boat engines again. To achieve my PK HP and speed I was spinning my engines ~6500 RPM that pushed my "legit" cruise speed to 5000 RPM's. There was never a real balance in prop pitch selection. Either spin the s#it out of them with a small wheel or load the engines with a bigger prop. Engines ran great, but running engines 6000+RPM's for miles that you hand built with your hard earned money just makes your guts pucker.
03-19-2019, 05:45 PM
#172
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Thread Starter
One thing he has going for him is that these are going into a 28 Daytona, efficient hull for sure. I had a 6300rpm BBC motor in my old 28 Profile cat, took some propping for sure. Small prop and still had to ventilate the prop to get it on plane, tried tubes like a #6 boat at first then found out the prop vent holes were enough to let it spin up to get it on plane. With twins he should not have as much of a problem as me planing. I always thought twin LS motors in a 28 Daytona would be killer, taking out a 1000lbs from big block weight would do that hull wonders as far as balance.
03-19-2019, 05:49 PM
#173
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Thread Starter
Engine get dropped at dyno Saturday. Should be dynoed by end of following week Will be ran on a Superflow 901. For comparison im gonna try to get some sheets from Larry of hp500 and 525 that have also been ran on hos dyno for apples to apples.
03-27-2019, 07:50 PM
#174
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I admit I have not had a chance to read your entire build thread. I was surprised early on to see you were using LS3 style heads. I have contemplated an LS build for years for either my current boat or preferably a better boat. I however would use a cathedral port head, most likely one of the aftermarket heads like a TrickFlow or AFR. I have seen several dyno shoot outs of max effort builds using both style heads and while the square port always takes the top number, it also is always sacrificing numbers down low and to me the peak number does not justify that short fall. I realize these are not max effort/max budget builds, so perhaps that was why you chose the stock LS3 heads over perhaps a stock cathedral head. At any rate I look forward to seeing your results and still plan to read the rest of your build. Good Luck. One last thing, I just had a memory post up of this build on my F/B wall and thought I would share it with the group.
https://www.enginelabs.com/news/vide...00-horsepower/
https://www.enginelabs.com/news/vide...00-horsepower/
Last edited by fastestbowtie; 03-27-2019 at 08:14 PM.
03-27-2019, 08:57 PM
#175
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Thread Starter
I admit I have not had a chance to read your entire build thread. I was surprised early on to see you were using LS3 style heads. I have contemplated an LS build for years for either my current boat or preferably a better boat. I however would use a cathedral port head, most likely one of the aftermarket heads like a TrickFlow or AFR. I have seen several dyno shoot outs of max effort builds using both style heads and while the square port always takes the top number, it also is always sacrificing numbers down low and to me the peak number does not justify that short fall. I realize these are not max effort/max budget builds, so perhaps that was why you chose the stock LS3 heads over perhaps a stock cathedral head. At any rate I look forward to seeing your results and still plan to read the rest of your build. Good Luck. One last thing, I just had a memory post up of this build on my F/B wall and thought I would share it with the group.
https://www.enginelabs.com/news/vide...00-horsepower/
https://www.enginelabs.com/news/vide...00-horsepower/
03-28-2019, 08:26 AM
#177
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iTrader: (1)
Im teally hoping the weight loss helps this baby get on plane easier. It can be a real pain. Was literally impossible with 4 blades. Had a good enoigh bite but then boost on old engines would kick in and blow them loose. Even dragging tunnel tab. Hopefully heavier nose now will help force her over
03-28-2019, 10:20 AM
#178
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Thread Starter
03-28-2019, 10:26 AM
#179
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Thread Starter
Built bravo drives. Imco nose cones. My problem is a) 1.5” above bottom b) boost on old engines kicked in hard before on plane amplifying torque and breaking props loose. Too much power is as bad as not enough in some situations. Measure your buddies prop depth. You would probably see it is flush with bottom. Mine compared to a flush setup is 12 mph faster
03-29-2019, 02:02 PM
#180
Registered
If I wanted more torque I would have went with Big Block engines. I’m still running the 1.65 Blackhawk drives. I’m after top end power at 6000-6500. My thoughts are a future update on drives and installing LSA superchargers. I like the broad power and of the 6.2 with its heads. I still should have more power and torque at any rpm range than compared to the MPI 350’s I had.
