LS DD maiden voyage

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keys2pines
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Re: LS DD maiden voyage

Postby keys2pines » Tue May 14, 2019 7:14 am

JGANT wrote:
keys2pines wrote:Sorry to dig up an old thread, but curiosity got me and I got bored after two pages. Was waterthunder able to develop a thrust bearing to run a DD LS?


I had been wondering the same thing. I thought I saw a post back on FB a while ago where WT said they had a meeting with a big name manufacturing company and they were going to work on a solution that’s been in the works for a couple years. I don’t think he mentioned specifically the thrust bearing, etc. but it sure seemed that is what was being implied.

I know one guy's dad that has a DD LS boat, didn't get into specifics, but he says it runs with his 0540 step. Maybe there's just not enough demand, the price for the "solution" is just more money that can be spent buying a gearbox.
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SWAMPHUNTER45
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Re: LS DD maiden voyage

Postby SWAMPHUNTER45 » Tue May 14, 2019 8:25 am

WaterThunder the LS expert built a DD LS about 4-5 years ago. It was ok if I recall but not super awesome.

Was down in StPete last week the guy Mr Branch and I use had a 427 LS on Dyno. He said it had a 4 inch stroke. For a DD car engine that sort of comes up a little short.

Your Old Detroit iron from GM ran longer back in late 60s and early 70s. For power below 5250 rpm stroke, head design and cam selection are the magic pill.

When you get to building stroker engines and talk about putting rpm in the mix the power output to to the moon and back with the right components. The problem is that you encounter a very increased piston speed. With every stroke the piston must dwell a period where it actually stops and then reversed direction. With the longer stroke the speed the piston moves at a given rpm is exponential and this causes fail.

Funny that stroked LS is over .50 (half) an inch shorter in stroke than my 542 and .60 than the 555 in the run stand now at the shop. Good example of why power can be made without spinning up high.

When you add .010 to a stroke of an engine it will result in more output than boring .030 that longer push on the piston translates into more usable power but the limit is piston speed as you add rpm to the rotating assembly.

Cadillac King out

CarMotorBarge
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Re: LS DD maiden voyage

Postby CarMotorBarge » Tue May 14, 2019 2:19 pm

Was that 427 LS on the dyno an LS3 or LS7?
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SWAMPHUNTER45
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Re: LS DD maiden voyage

Postby SWAMPHUNTER45 » Tue May 14, 2019 4:10 pm

I don't know? Mr Branch asked about the stroke length and the builder said it was a 4 inch stroke.
Think it had LSX heads but I am not certain.

terrible ted
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Re: LS DD maiden voyage

Postby terrible ted » Wed May 15, 2019 12:49 pm

I will say fuel economy on my old 350 dd was great in comparison to a 520 540 and a cad dd boats I ran with. I know I ran a 30 gallon tank from 50 to the oak head and back when the water was low. With two on board a 13 foot cotton mouth back in the days of wood props. Yep every dd sb I had developed crank play. That is what eventually killed car motors for me.

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digginfool
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Re: LS DD maiden voyage

Postby digginfool » Wed May 15, 2019 7:54 pm

Rumor has it there's a Benny with a DD WT 427 hitting the water soon. Supposedly made over 1,100 lbs of thrust on the test stand. JS

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