Dissection of the LS Engine

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Toobuilder

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Finally found a mule to play with! I've torn it down enough to establish overall condition and have a look at the architecture. With an eye towards a direct drive and inverted operation, I've been looking at some of the detail parts and areas to save weight by modification or outright omission. I'm quite impressed with the engine, but there are plenty of opportunities to save shed some fat.

I'll post some detailed pictures before too long with some examples of weight savings ideas, but this thread hopefully will grow into an exposé on the possibilities of the LS series.

Also, this is my first post after changing my whole home IT system (now I'm smartphone based), so it's going to take me a while to figure out how to upload pics and stuff, so bear with me.
 

revkev6

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Finally found a mule to play with! I've torn it down enough to establish overall condition and have a look at the architecture. With an eye towards a direct drive and inverted operation, I've been looking at some of the detail parts and areas to save weight by modification or outright omission. I'm quite impressed with the engine, but there are plenty of opportunities to save shed some fat.

I'll post some detailed pictures before too long with some examples of weight savings ideas, but this thread hopefully will grow into an exposé on the possibilities of the LS series.

Also, this is my first post after changing my whole home IT system (now I'm smartphone based), so it's going to take me a while to figure out how to upload pics and stuff, so bear with me.

what LS engine did you get!
 

Toobuilder

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Once I have my way with the 4.8, I'll look to build a big one. The baby will demonstrate most of all the mechanical integration problems, so well see where that leads me.
 

RJW

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Finally found a mule to play with!
Great! I can’t wait to see pics and hear your take on the motor. There is a lot of questionable info floating around. It will be nice to get clear, objective, and relevant comments. I really like the inverted DD configuration.

I really must start collecting these motors. My usual sources for junk motors seem to have dried up. I guess I haven’t been doing enough crappy car work lately.

Rob
 

Toobuilder

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Are you speaking of an essentially stock "crate" engine (EFI, computer, etc)? If so, that might just lead down the typical path with auto conversions. As I dig more into this engine, there appears to be plenty of room for minor tweaks that should collectively provide real gains in cooling, oiling, and weight. In short, there are no doubt some successes with factory built engines, but I'm thinking the engine should be built from the ground up as a flying engine. There are still plenty off off the shelf (or nearly so) parts available for high output (aviation) use, but the dream of a turn key engine from the local Chevy dealer is a little optimistic- JMHO
 

Toobuilder

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So as a quick update, I am just about finished with a prop adapter for the end of the crank. As soon as I can get the pictures uploaded, I'll provide a more interesting discussion.
 

rv6ejguy

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Are you speaking of an essentially stock "crate" engine (EFI, computer, etc)? If so, that might just lead down the typical path with auto conversions. As I dig more into this engine, there appears to be plenty of room for minor tweaks that should collectively provide real gains in cooling, oiling, and weight. In short, there are no doubt some successes with factory built engines, but I'm thinking the engine should be built from the ground up as a flying engine. There are still plenty off off the shelf (or nearly so) parts available for high output (aviation) use, but the dream of a turn key engine from the local Chevy dealer is a little optimistic- JMHO
Really, I was interested with people having flight experience with an LS in any shape or form.
 

RJW

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Yeah! Cool! Let’s see the pics no matter how crappy. The phase of development that you are in is (to me anyway) by far the most fun. I like shiny finished things but it’s a real blast tearing stuff apart to see how it works.

Rob
 

Toobuilder

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Yes, that is the design objective.

Also just became aware of a Tall deck modification which can be added to the stock blocks which takes the engine out to 500 ci. Not cheap, but with a 4.5 inch stroke, that thing would swing a big prop like a Lycoming!
 

revkev6

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Yes, that is the design objective.

Also just became aware of a Tall deck modification which can be added to the stock blocks which takes the engine out to 500 ci. Not cheap, but with a 4.5 inch stroke, that thing would swing a big prop like a Lycoming!
what is the modification?? I've heard of aftermarket blocks that you can buy but not a modification like a spacer??
 

revkev6

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wow, that thing is both awesome and really scary at the same time! it would make for an ideal torque monster on the low end! use the small truck heads and intake with that block and you would really have something for direct drive
 

Toobuilder

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I agree, lots of potential there for DD. I think it's only available as a fully completed short block (to your specs) for around $14k. Pricy, but it has all the premium internal parts available.
 

Jay Kempf

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Yes, that is the design objective.

Also just became aware of a Tall deck modification which can be added to the stock blocks which takes the engine out to 500 ci. Not cheap, but with a 4.5 inch stroke, that thing would swing a big prop like a Lycoming!
Big prop isn't mandatory. You can suck up a lot of HP and generate a lot of thrust with the equivalent multiblade with a lot of pitch. Seems that cheap big torque is suited to a direct drive 72" ish 3 blade with ground adjustable blades but fixed pitch in flight for most of the speed regime of a small plane. You might sacrifice a little acceleration from a stop but not much else unless you are looking for STOL capability.

What target T and HP at what RPM are you shooting at?

And one more question: is the front and rear of the 6 the same as the 8 so that it share's the same boltup capability for accessories and your new drive. Seems like it should be. That would be a coupe.
 
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