Turbo charged Lycoming

[RV7Guy]

I posted in the Engines section but I think many may have missed it. I've done some research and can't find much. Anyone got any input?

Saw this on Aero-News.net. A new Lycoming turbo charged IO360 for the Experimental world.

Wow, wonder if it will work on a RV? Can the Clone manufacturers be close behind?
http://www.aero-news.net/index.cfm?C...y=%2Findex.cfm
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[Tandem46]

Darwin,

Your link works, but just goes to the current Aero-news.net page. This link should work if this is what you're talking about:
http://www.aero-news.net/news/genav....ws%2Fgenav.cfm

[breister]

The "clone manufacturers," specifically Superior, were actually ahead on this with a turbo-normalized firewall forward package exclusively for Lancairs.

However, there were NUMEROUS problems with the package and they have pretty much abandoned it.

Maybe this will get them to try again.

<Edit> Don't forget, the RVs have a VNE which might be exceeded in level flight at altitude with a turbo. Previous posts have expressed concerns that flutter might be experienced with tragic results, although I haven't heard of any in-flight RV breakups. If you decide to go turbo, please be careful!

[gmcjetpilot]

Normalizing turbos of Ray Jay have been around since the 1960's.

Lycoming does not recommend turbo engines that where not made for turbo.

Many LONG LONG threads on the subject of how little gain a turbo is in an RV are on this forum if you use the search function.

Bottom line you need to fly into the low teens to get your use out of it. Than you are sucking O2 and than running onto Vne (true airspeed).

Superior had the IDEA to offer an engine with turbo for experimental gave up because the cost of the kit was too great, almost as much as the basic engine. I saw it at Oshkosh in 2004? I called them about something else a year or so ago and asked. That is when they said they shelved it. I think it was before the buyout.

Plus weight and a small cowl would make installation of turbo, wastegate and inter-cooler a pain the back. You really want an inter cooler. There is a RV8 turbo and the plumbing is a monster. He said what kind of speed and fuel burn he got and it was not a quantum leap. Again you have to go up into the teens to get any benefit. Do you fly up there a lot. If all you did was long cross countries over mountain ranges in the Denver area, it might make sense. Most RV's don't get about 3,000 feet for local flights, which make up 80% of they flying RV'ers do. Remember normalizing does not ADD power at all, unless like I say you fly out of Denver (or other high hot airport).

I highly recommend you forget turbo. RV's are not a good match for the machine and mission. If you want more altitude performance get a bigger HP engine, IO360 or IO390 200/210 HP engine. Although 180 HP is plenty for most pilots.

[RV7Guy]

Originally Posted by gmcjetpilot

Normalizing turbos of Ray Jay have been around since the 1960's.

Lycoming does not recommend turbo engines that where not made for turbo.

This IS a Lycoming from their Thunderbolt line. I love flying high. With the added power you can throttle back, get great efficiency and speed within the proper limits.

Just asking for information. Putting a 6 Cylinder on a 6, 7, or 8 isn't recommended but there are plenty of them flying and they haven't fallen out of the sky yet.

[osxuser]

A turbo'd parallel valve is a good idea, but I almost wonder if for the extra weight, a IO-390 or Parallel valve IO-540 wouldn't be a better idea. The turbo gets you back something at altitude, but doesn't help the climb really, and the RV isn't IDEAL for higher altitude flying with it's short fat wing.

That said, i've considered a whole slew of things like this when looking for engine options on my projects. My current favorite idea is a supercharger with a clutch (only around 4-5 PSI of gain, only used at altitude).

[rv6ejguy]

If you are climbing high, even a normalized engines makes a big difference in climb rates and times to cruise altitude. At 5K you are down to about 83%, 10K- 69% and 15K- 56% power. My ROC stays pretty steady through 14,000. I've used O2 only once and that was on a test flight for max speed.

I do agree that unless you like to suck O2 and fill the bottle frequently or actually do fly out of high elevation airports and in the mountains, turbos don't make a lot sense on RVs for most pilots.

Since I had the sense knocked out of me a long time ago following some mountain bike endos, I have turbos on both my RVs.

The only substitute for cubic inches is boost.

Done right to the right engine, I don't see many reasons why it should not be reliable and require little more maintenance than an atmo Lycoming. It will add a fair weight penalty though, no escaping that and probably add a bit more drag through increased cooling airflow and intercooler airflow. Always compromises. I haven't looked at the hardware Lycoming uses on this- (I hope it is not the old school stuff they used 30 years ago) but hopefully the factory has done it right.

[osxuser]

Originally Posted by rv6ejguy

If you are climbing high, even a normalized engines makes a big difference in climb rates and times to cruise altitude. At 5K you are down to about 83%, 10K- 69% and 15K- 56% power. My ROC stays pretty steady through 14,000. I've used O2 only once and that was on a test flight for max speed.

I do agree that unless you like to suck O2 and fill the bottle frequently or actually do fly out of high elevation airports and in the mountains, turbos don't make a lot sense on RVs for most pilots.

Since I had the sense knocked out of me a long time ago following some mountain bike endos, I have turbos on both my RVs.

The only substitute for cubic inches is boost.

Done right to the right engine, I don't see many reasons why it should not be reliable and require little more maintenance than an atmo Lycoming. It will add a fair weight penalty though, no escaping that and probably add a bit more drag through increased cooling airflow and intercooler airflow. Always compromises. I haven't looked at the hardware Lycoming uses on this- (I hope it is not the old school stuff they used 30 years ago) but hopefully the factory has done it right.

Agreed, but 75% (generally climb HP on the lycs) is 135HP for the parallel valve, only 64% for the IO-390 (So maintainable up to about 12K?). 52% for a parallel O-540 so maintainable up to about 16K...? You see where I'm going. No free ride either way. I know the rotary is a LOT more responsive to boost than a lycoming too, boost tends to reduce life considerably, probably due to higher temps, which could be solved, but like you say, more cooling drag.

Edit: I don't know why I thought you had a rotary, either way though, I'm guessing the sube responds better to boost than the lyc.

[rv6ejguy]

Yep, any engine with good port flow responds well to boost (4 valve Sube, Wankel etc.) I only run 38 inches for TO and 35 for climb. Turbos maintain full SL power (100% MCP) to critical altitude. Critical altitude on my present installation is limited by intercooler performance, hence induction temperature rather than the turbocharger which will do 35 inches to about 28,000 feet, depending on OAT with the new compressor. You may be limited by turbine inlet temp, CHT, IAT, oil temps, a fully closed wastegate, N1 limits of the turbo machinery or in some cases, compressor surge limits. Lots to consider, especially above 20,000 or so.

The RV10 twin turbo installation will have far superior intercooling and the turbos are matched for the 8000-17,500 foot mission. Mainly doing this for the smoother ride and a bit more TAS plus the easy ability to catch the favorable winds sometimes. High altitude gives us some more gliding options too. I'm hoping for a solid 2000 fpm at medium weights right through 17,000.

I know most Lyco guys with RVs keep it firewalled in the climb. Is this not common practice? That's how I flew Lycomings.

I'm guessing that more Lancair guys would be interested in the normalized Lycoming than RV guys. They have a higher Vne.

[osxuser]

Most everyone I know with a lyc runs 25" 2500 RPM in the climb (CS), with a fixed prop full throttle and whatever RPM they can get (around 2400 usually with a cruise prop...)

Keeping temps down as it climbs would be a REAL challenge at 28" ad 2700 RPM.