Chevy LS conversion.. what are your thoughts?

the4ork · #1 08-09-2007, 10:27 PM

more power and near equal fuel consumption as a 540, with the downside of running a redrive...

what are your thoughts on stuffing one of these in a 'modified rv-4' i.e rocket?

my thoughts are: a. i'd love the extra HP, you cant beat 520 hp and 600ft lbs of tq

*seems* like the fuel injection system is the way to go, but i would HAVE to go fully programable (standalone) unless it comes so already (not sure) this way you are able to lean/richen it out, and can have variabe 'modes' such as take off, cruise, max power, hot day, cold day... you could load tons of maps up that you can switch to...

the re-drive, this is the only thing im weary about... seems like they have had alot of trouble in the past but are getting better (am i right?) but is there a re-drive out there that can handle the 520hp v8 reilably? i know their out there, but reliabilty becomes a question at this hp level?
not only that, what if i decide to do some mods? a low boost turbo setup? 5-6psi? that could easily boost the power up to 600hp

for me, if it wasnt for the re-drive i'd say case closed im going V8...
but unless u guys change my minds drastically i think that will be the route i persue...

one last question...

lets say my 520hp v8 rocket has the same amount of drag as a regular 540 powered rocket (prably wont due to radiators etc...) but how fast *could the rocket go with 505hp? 275-300mph?

http://www.epi-eng.com/ET-Eng-Gen-2.htm

rv6ejguy · #2 08-09-2007, 10:44 PM

EPI http://www.epi-eng.com/ET-LS-CrateEng.htm has some pages on the LS-7 engine and their thoughts on what internal changes might be required for reliability at this hp level in aircraft. Looks like their new Mark 15 drive would be the trick. Money wise, you'll be close to the IO-540 when you are done but with a lot more power. Weight wise, I'd expect it to weigh 75-100 lbs more than an IO-540. Drag wise, with proper design, you should be able to equal or slightly better an air cooled installation. Delphi currently produces a nice ECU for use on these engines and we are working on one now for the smaller LS engines first.

I think even in atmo form, this engine would move you into untested flutter zones. Might have to do some structural mods to the engine mount pickup structure as well. Turbos would add too much weight.

Find some good prices here: http://www.crateenginedepot.com/stor...y_ID=53&Page=2

$13K for the long block, 11K for the drive and lots of misc pieces.

Would look and sound way cool!

Do it!

the4ork · #3 08-09-2007, 10:55 PM

a non intercooled turbo setup wouldnt add any more than 25lbs...

of course this would be my only plane, so turning it into a reno racer wouldnt really be smart, but who knows, it may turn into one someday?

i just went through the epi website and i edited out the LS-7 stuff for the Gen-2 engine related stuff... since the gen2 is more aviation specific and the LS7 is pretty hard to find not to mention expensive plus it still needs work...

the4ork · #4 08-09-2007, 10:57 PM

Quote:

Originally Posted by rv6ejguy

EPI http://www.epi-eng.com/ET-LS-CrateEng.htm has some pages on the LS-7 engine and their thoughts on what internal changes might be required for reliability at this hp level in aircraft. Looks like their new Mark 15 drive would be the trick. Money wise, you'll be close to the IO-540 when you are done but with a lot more power. Weight wise, I'd expect it to weigh 75-100 lbs more than an IO-540. Drag wise, with proper design, you should be able to equal or slightly better an air cooled installation. Delphi currently produces a nice ECU for use on these engines and we are working on one now for the smaller LS engines first.

I think even in atmo form, this engine would move you into untested flutter zones. Might have to do some structural mods to the engine mount pickup structure as well. Turbos would add too much weight.

Would look and sound way cool!

Do it!

is that your SDS powered RV? i've seen that thing in their website a long time ago when i was looking at going standalone on my volkswagen... i went standalone on a 16v turbo VW mkII GTI

except i went with 034EFI Stage Ic from 034motorsport.com way cool system

rv6ejguy · #5 08-09-2007, 11:07 PM

A single turbo alone for this monster would weigh a lot more than 25 lbs with the wastegate and headers. Intercoolers are a must on aircraft, especially with this CR.

Yep I fly the Turbo Subie RV6A.

Sorry to hear you have a 034 on your VW.

Kidding. Hope it is working well for you.

I'd be going with an LS-6 I think. They are about $9K cheaper.

asav8tor · #6 08-10-2007, 01:22 AM

Insurance, call I don't think you will like what they have to say.

If you have limited earning potential and your net worth is very low, you can fly without insurance. The law dogs will leave you alone if there is nothing to recover.

Resale, probably more than 95% of potential buyers will steer away.

If you don't ever plan on selling not a factor.

Geico266 · #7 08-10-2007, 02:51 AM

Alot of things look good on paper. I have seen more auto converstions taken off and a "regular" engine put back on than the other way around. I just have not seen the auto conversions get the # of hours needed to off set the reliability of an aircooled, in line, aircraft engine.

Reliability & resale, it would be a huge mistake. IMHO

Don't start yelling at me, I just call them as I see um.

pierre smith · #8 08-10-2007, 05:21 AM

Quote:

Originally Posted by the4ork

one last question...

lets say my 520hp v8 rocket has the same amount of drag as a regular 540 powered rocket (prably wont due to radiators etc...) but how fast *could the rocket go with 505hp? 275-300mph?

http://www.epi-eng.com/ET-Eng-Gen-2.htm

I'd be more concerned with the airplane shedding its rudder or elevators. This was seen to happen to a -4 in Australia. Flutter is usually disastrous so be prepared to spend more money yet on Aero engineers to calculate and design into your airplane what it would take to raise the redline to 300 MPH or more.

Good luck,
Pierre

Jconard · #9 08-10-2007, 05:47 AM

I might advise taking a flight in an existing 10, before going forward. I flew in one a month or two ago, and we had four bubba's in the plane, full fuel, and some baggage. By "bubba's" I mean 215-255 lbs big guys.

Now, not only did we have a luxurious amount of room, but the takeoff roll was like a rocket ship. We were off the ground in like 300-375 feet and climbing like a homesick angel.

There is just no need to put a 500+ HP engine on this thing. This fascination with such HP installation seems a bit like installing a brass finish nail with a sledge hammer. In addition, even with the correct (lycoming) engine installed the 10 is a bit nose heavy. Many people find them easier to land, with either a bag of sand or some passengers in the back. If you put the extra 100 lbs...and it will be at least that, on the nose, you may be out of forward CG when landing solo.

It is not the platform to go racing in. It is a four seat family cruiser.

I know the RV6EJ said that you will/may get better drag numbers, but that is simply a dream. The truth is that HE may get close. He may get closer than anyone has so far. But if you got to his website you will discover that there are few people who can match his development and fabrication efforts. You also have physics working against you on the thermal transfer side. What you can count on, based on the overwhelming history is :alot of weight, alot of complexity, reduced resale value, and possibly an impossible to insure airplane. In exchange you will get a slower plane which burns more fuel, or you will simply throw huge HP at it and get a slightly faster plane which burns A LOT more fuel.

Finally, this has been covered many times, and at great length....you WILL NOT GET the same hp at better fuel flow. Energy is never created or destroyed, there is only a certain amount of fire in a gallon of gas. The Lycoming engines, especially in cruise regime already produce specific fuel consumptions (relative to HP) in a range that very few non-stationary engines will match.

I suppose it bears saying that Van's and Lycoming, and Continental are aware that we live in a world where cheap, high quality, high horsepower V8's are available for crate sale. Now, do you think there is a reason why they have not adopted the technology, or partnered with the suppliers?

TSwezey · #10 08-10-2007, 06:55 AM

I believe he is putting this in a Rocket not a -10. If he is using the EVO wing he will need some forward weight from what I have been told. I don't think he needs an LS6 or 7. I think he could get plenty of power from an LS2 with a supercharger. I doubt the tail section of a Rocket could handle 300 MPH. I wouldn't want to be the one to test it! I will never push my -10 past Vans Vne. When will I use the full power of the engine? For short field takeoffs at high DA's and probably to see what altitude I can fly to. If I wanted 300MPH I would buy a Titan p-51 and put an LS6 in it. I certainly would try to modify an RV to do it.