LS-3 Powered Velocity

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Voidhawk9

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Definitely one to watch!
Anyone know how he intends to feed the radiator? I assume another inlet in the lower cowl.
 

pfarber

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Motor sounds great. Should be a nice preforming aircraft.
LS3 is a 300hp+ motor.. it can make a bag of bricks perform like a PITTS

Looks like a FWF package.. $50k or so IIRC

Get it down to $10k and you have my attention.
 

pfarber

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Only issue I see is that as everyone should know, the 1st flight is Tuesday.

BTW, let me know where you can buy a 300HP aircraft engine *crankshaft* for under $10k, and you'd have my attention. ;-)
Crankshafts are cheap. Its that little piece of paper that costs all the money. And no, its not about liability or volume. Its about Lyc/Cont simply forcing GA to pay whatever it wants,
 

TFF

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Good crankshafts are not cheap. A good Chevy crank truly airplane quality is about $2500. Not some cheap Eagle junk. Lycoming only makes about 1500 new engines a year now. That ain’t much. A couple of times Lycoming farmed out cranks. Nice big hairy ADs. One a judge ruled that they could sell no new engines until all the customers that had a bad one was taken care of. Took Lycoming a year to make new cranks before to sell new engines. This was about 2003. 50% is cost to build 50% is for lawyers.
 

TXFlyGuy

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So that is not an LS3. Based on the 495 hp, it has to be an LS376/480. That engine has the GM Hot Cam factory installed. Our V8 did 525 hp on the dyno, at 6000 rpm.

This is a twist...running as two V4's? Why? Would it not be just as desirable to have both ECU's power the entire engine, with the option of selecting one ECU at a time?

And that engine will only set you back around $7,700. Delivered to your front door. And that includes the GM Hot Cam.
 

rv6ejguy

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Good crankshafts are not cheap. A good Chevy crank truly airplane quality is about $2500. Not some cheap Eagle junk. Lycoming only makes about 1500 new engines a year now. That ain’t much. A couple of times Lycoming farmed out cranks. Nice big hairy ADs. One a judge ruled that they could sell no new engines until all the customers that had a bad one was taken care of. Took Lycoming a year to make new cranks before to sell new engines. This was about 2003. 50% is cost to build 50% is for lawyers.
You can get quality forged, heat treated 4340 SBC cranks from Callies or Lunati for well under $1000. Similar quality to what's in a Lyc.
 

TXFlyGuy

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You can get quality forged, heat treated 4340 SBC cranks from Callies or Lunati for well under $1000. Similar quality to what's in a Lyc.
No doubt. One thing we chose was to remain all OEM stock. No after market cams. Yes, we contacted several manufacturers. As GM offered their factory Hot Cam, we felt comfortable going that route. And it was not terribly expensive. I think you can get one from GM for around $700 or so.

Why would anyone want to change out the OEM crank in an LS3?
 
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TXFlyGuy

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LS3 is a 300hp+ motor.. it can make a bag of bricks perform like a PITTS

Looks like a FWF package.. $50k or so IIRC

Get it down to $10k and you have my attention.
Just for comparison, the complete FWF package from Titan will run you close to 60 big ones.

The only difference between grown men, and little boys, is the price of their toys.
 

TXFlyGuy

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Depends on the RPM you want that 525.

... And no, 525 is not enough.
Ok. Let us know how much is enough. That will give everyone a target to shoot for. In our case, we have a max 430 hp available, due to rpm limits, with a max gross operating weight of 2250 lbs. On an airplane that was designed around a 100 hp engine. For my purposes, that is more than enough. And that power is with an engine that is complete factory OEM stock.

How much hp is available on the V8 Velocity in this thread? Maybe he wants to upgrade to a new crank/cam? What is the PSRU?

You can't really talk about horsepower in a vacuum. It needs to be factored in with the total GW of the aircraft. In my case, around 5.2 lbs/hp is the figure. A WWII P-51 was in the range of 8 lbs/hp.
A modern C-172 comes in at 15 lbs/hp.

Still curious as to the logic in operating as two V4's? Is this the best possible solution?
 
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Toobuilder

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Ask the Reno guys how much HP is "enough".

From a more practical standpoint, a long stroke in an LS based engine is one of the keys to any hope for a successful direct drive conversion. Without going to forced induction, more displacement is the only way to churn out the required power at a normal propeller RPM.
 
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