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Then no way to know stingy or graceful a dyno is.

Quote:

Originally Posted by mggdoors (Post 4685145)

Im sure they will considering I have the ability to rev it if I choose to

Maybe if you run 1.65 drives?

This is what I see:

At 3200 rpm you are giving up 110.6 ft lbs of TQ and 67.4 HP.
At 4200 rpm you are giving up 128.1 ft lbs of TQ and 102.4 HP.
At 5400 rpm you are giving up 31 ft lbs of TQ and 32.5HP At this point yes the 525 is done but
At 6200 rpm (Where you stopped) you now are 80 ft lbs of TQ less then the 525 was at 5400 and still down 10.6 HP.

There are others on here that may share some insight but yes you can spin faster but it is going to be a much small prop or if you go to a 1.65 you may spin more prop but the prop speed will only be 157 rpm more at 6200. At say the same slip and 28 pitch props (pretty close to what most 525's run on a step V. Lets just say 12% slip the 525 would be 83.99 mph at 5400, the LS would be 87.66 at 6200 rpm. Pretty good gain if it will pull the prop. But I bet everywhere else below 5400 the LS motor will not have the punch the 525SC has.

But that is just me, idk but I will be following as this next winter its time for a repower for me.

I guess when it hits the water we will know.

Quote:

Originally Posted by Wildman_grafix (Post 4685171)

Maybe if you run 1.65 drives?

This is what I see:

At 3200 rpm you are giving up 110.6 ft lbs of TQ and 67.4 HP.
At 4200 rpm you are giving up 128.1 ft lbs of TQ and 102.4 HP.
At 5400 rpm you are giving up 31 ft lbs of TQ and 32.5HP At this point yes the 525 is done but
At 6200 rpm (Where you stopped) you now are 80 ft lbs of TQ less then the 525 was at 5400 and still down 10.6 HP.

You pretty much summed up why you wont find 400ci small blocks in a 2019 Top Gun.

On point phil.

I’ve yet to see an NA LS outdo an NA big block though we keep seeing people try. There was the 650hp set for sale for a long time and the speeds posted by the owner with a sunny I think were on par with a 500efi version. Always interesting to see though.

Quote:

Originally Posted by Crude Intentions (Post 4685186)

Do you have any clue why they where on par with 500efi?? I do. I spoke to dennis personally about this. The weight reduction cause the bow to be too heave in turn driving the nose through the water. He also stated that the ass end sat substantially higher put of the water. The power was there. The boat in my opinion needed more cupping on the props or possible drive spacer for leverage

Those were tye "650hp" ones....ran 88mph in a 32 sunsation....which is what they run with 500efis or darn close. 300 more hp, a few hundred lbs less weight, should have made it faster than a 500efi boat.

Then again, maybe they didnt actually make 650hp, the dyno just said they did.

Ok. Just saying. I’ve yet to see a set go in a boat and outdo the big blocks. Maybe you’ll be the first.

I really enjoy these projects and learn a great deal from them. They seem like a great set up for something like a twin 29’ Outlaw where that much junk in the trunk makes them porpoise like a chunk monkey on a single ski.