Anyone flying Chevy V-6?

I'm curious if you guys running this engine are happy with the performance? Looks like a few using the Belted Air Power PSRU. I read that very long thread about the alternate conversions. I didn't see any mention of the 4.3 Chevy V-6! I feel this is a good engine. Yes it is heavy. Yes it will turn more rpm's than a lycoming. However 200+ hp is easily within reach, and it will cruise anywhere from 3200 to 4000 rpm depending on tuning/psru, etc. I'm not set on this engine, but it is MY first choice, followed by a worn out Lycoming core that I would rebuild. TIA
Boyce

RAMPEYBOY said:

I'm curious if you guys running this engine are happy with the performance? Looks like a few using the Belted Air Power PSRU. I read that very long thread about the alternate conversions. I didn't see any mention of the 4.3 Chevy V-6! I feel this is a good engine. Yes it is heavy. Yes it will turn more rpm's than a lycoming. However 200+ hp is easily within reach, and it will cruise anywhere from 3200 to 4000 rpm depending on tuning/psru, etc. I'm not set on this engine, but it is MY first choice, followed by a worn out Lycoming core that I would rebuild. TIA
Boyce

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Boyce,
I talked to Belted Air Power several times about their conversion. There aren't many in the field. This doesn't make it bad, there just isn't a lot of info available. I know of someone using a Chev V-6 in a Starduster 2 of all things! He has had reasonable success, (the plane flies), but hasn't put a lot of time on it. Don't know the details of PSRU or other items.
Bill Jepson

Someone here in Albany, Or

There's a local guy here that has a Chevy 4.3 V6 in a 6a. Which he has been flying a couple years or so. I'll see if I can get some info from him. I have no clue whether he frequents this forum or not.

I got a site for you

http://www.beltedair.com/Default.htm
http://www.beltedair.com/KitPlanes.htm

Nothing fancy, no claims or pomp and circumstance, just good basic design using very basic (read reliable and dirt simple) technology.

Belt - Check good and reliable, no harmonics
Carb - Check good No electronics
Ignition - Check good No electronics

Seems to be an alternative. Why not as popular? I don't know the Subaru and Mazda get more play, but a V6 seems pretty elegant. I am by the way a dyed in the wool Lycoming fan, but can appreciate a good effort.
George

Been around a while....

If you want to check the RV-LIST archives. I'll bet those guys have been around for at least 6 or 7 years. I think they were quite active on the RV-LISt when they developed their first prototype engine.

As for popularity, the only "popular" alternative seems to be the Subaru that comes in a FWF kit. These are starting to appear in some numbers. I think most of us have enough work to do building the plane without taking on another large project in the engine. As evidence, I cite the popularity of the quick build kits. Without a FWF kit, I suspect that any alternative will be confined to the minority looking for a more interesting project.

My .02

John

As for belt drives and harmonics or torsional vibration (TV), all types of redrives can suffer from possible TV whether belt, chain or gear. This is a complex interaction between the crankshaft, flywheel, redrive and propeller. The Chev V6 belt drive mentioned had an avoid band around 3000rpm if I remember correctly. This is not an area used in flight much fortunately. This engine is on the porky side but has accumulated many hundreds of flight hours successfully and is reasonably priced although you must assemble the package.

EcoTec looks cool

william weesner said:

can't you get most of these parts in aluminum.

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Yes, belted power seems to be very conservative, which is a good think, but no doubt you can shave some lbs off with after markert parts. I think most of the parts are aluminum as is.

HERE IS A COOL ENGINE:

Ecotec 2.0L Supercharged Production Engine: This supercharged 4 cylinder Crate Engine (RPO LSJ) features the following: DOHC with Sequential Fuel Injection Bore is 86.00 mm and Stroke 86.00 mm with 9.5:1 compression ratio 205 Horsepower @ 5600 RPM and 200 lb-ft @ 4000 RPM torque: http://www.gmgoodwrench.com/perfparts/images/parts/large/12499466_large.jpg

The V6 engines come in 160hp to 260hp super charged versions, but think they are cast iron. No doubt the racers have aftermarket aluminum heads and blocks if GM performance does not already.

The EcoTec is sold as a crate engine and I think the hot rodders have gotten some cool aftermarket stuff for it. Seems like an interesting engine.

George

Thanks for the replies guys. I'm familiar with the Belted Air power people. I plan to use there PSRU if/when I decide. I was hoping to hear from some satisfied customers on the installation of this engine. By the way, Brodix now offers aluminum heads for the engine. GM offers aluminum heads and block. The aluminum GM heads seem to be quite a departure from the stock engine design. The Brodix heads look more doable. I like the engine/theory because it is relatively low revving (3000-3800) as compared to other auto conversions.

I think the aluminum heads and block saves around 70 lbs. which is huge. Bad thing is they're pretty expensive but cheaper than a Lyco still. If this turns your crank go for it. Lots of cubes so you should be able to turn it slower.

Some people say the auto conversions have trouble running at high RPM for extended periods. Personally I see no problem with the 3000-4000RPM range. Older vehicles before the common use of overdrive would run pretty close to that all day. My father's F150 with 300 6 cyl, runs about 3200 rpm at 65mph. We frequently used it to pull a boat or camper at those speeds for hours with no trouble. Now, if it were asked to run 6000rpm for hours with no internal mods, I may agree with the doubting Thomas' opinion..

Costs?

Short of emailing and/or calling the company, any general ideas what the V-6 complete kit costs?

I see that they offer the mount, headers, etc......

Thanks-

I looked at their site last week, and the figure they quote is approx $13K installed using a brand new GM crate Vortec.

RAMPEYBOY said:

Some people say the auto conversions have trouble running at high RPM for extended periods. Personally I see no problem with the 3000-4000RPM range. Older vehicles before the common use of overdrive would run pretty close to that all day. My father's F150 with 300 6 cyl, runs about 3200 rpm at 65mph. We frequently used it to pull a boat or camper at those speeds for hours with no trouble. Now, if it were asked to run 6000rpm for hours with no internal mods, I may agree with the doubting Thomas' opinion..

Click to expand...

Some others flying this engine are running them in the 3600-4400 rpm range for cruise/ takeoff respectively. The Ford V6s run similar rpms with no problem. The Subies are running 4000-4900 rpm no worries.

Chevy V-6

Am I crazy for thinking that the Chevy V-6 (modified to also accept AVgas) is a VERY viable option for power?

I must admit that I have done very little research on the subject so far, but the previous posts have had me very intrigued for the past few days.

Am I missing any obvious 'concerns' such as icing, or ????

I wouldn't even consider it except for the facts that it seems to be a very reliable option with little press thus far. The guys who developed the reduction package have flown this configuration in everything from a Globe Swift to an RV for countless hours with no issues reported. I have seen and heard the Subie RV's, and I know those followers are dead set on that option.

But, any other thoughts, opinions, or pro's/cons for the V-6? It sounds so simple, especially since a full FWF package is now offered. Alloy heads, special cam and other internal components seem very simple.

Am I missing something here?

Thanks in advance- I'd really like to keep this thread rolling and get everyone's opinions!

Too much power/weight can turn a sweet plane into a beast. This might be the case with the -9. I'm not real familiar with the mission of the -9, but I thought it was really for the 118-150 horse engines, such as the 235, or 290/320 lycomings. But hey, if the glove fits, wear it!

RAMPEYBOY said:

Some people say the auto conversions have trouble running at high RPM for extended periods. Personally I see no problem with the 3000-4000RPM range. Older vehicles before the common use of overdrive would run pretty close to that all day. My father's F150 with 300 6 cyl, runs about 3200 rpm at 65mph. We frequently used it to pull a boat or camper at those speeds for hours with no trouble. Now, if it were asked to run 6000rpm for hours with no internal mods, I may agree with the doubting Thomas' opinion..

Click to expand...

You have to remember that swinging a prop on a plane is like driving uphill, pulling a trailer, all day reguardless of the RMP. Your truck/car is pulling very low man pressures to sustain 65mph. I have personally seen subie engine internals fail multiple timeson aircraft. Usually rods.

Best,

To fly or Tinker

txaviator said:

Am I crazy for thinking that the Chevy V-6 (modified to also accept AVgas) is a VERY viable option for power?Am I missing something here?

Thanks in advance- I'd really like to keep this thread rolling and get everyone's opinions!

Click to expand...

Yes you are crazy.

No seriously the two biggest problems I see with all the auto conversions: WEIGHT and DRAG. A secondary issue is the propeller.


WEIGHT: I have never seen any auto conversion beat a Lycoming for lower weight. The PowerSport Rotary engine kit came close, a few more lbs than a 200HP Lycoming. However the 200hp Lyc installed weight is about 20-30 lbs more than a 180hp. Bottom line auto engines weight about 60-100 lbs more, usually more towards the 100 lbs. If there is any argument look up the empty weights flying RV's with Subaru, Mazda and V6 installations and compare to equivalent RV's with 150hp, 160hp, 180hp and 200hp. All the auto conversions are heaver. As the one guy stated, to paraphrase, "Too much power or weight can turn a sweat plane into a beast."


DRAG: The RV airframe is designed for air cooling. Air cooling is very efficient from an airframe cooling drag stand point. Auto engine folks will go on how superior water cooling is. IT IS!! Its great for heat transfer internal to the engine. However it does not mean its superior for reducing airframe drag and going fast. Again PowerSport was one of the first to use a chin scoop (cowl from Sam James) to do something about reducing the drag of forcing fast air thru a radiator. They where rewarded with decent speed compared to the Lycoming, albeit at the expense of much higher fuel burn, which is a particular CON of rotary engines, high fuel flow at high power. Look if an airframe with a radiator cooling tunnel in the fuselage or wing radiators was designed around a water cooled engine, than yea, hell yea! However stuffing a water cooled engine in an airframe meant for an air-cooled engine is a "work around" at best. Look at a P-51 real close and tell me what you see. That big chin scoop by the way is for the carb induction not cooling. The radiator's on the belly in a scoop, has carefully engineered ramps and exit diffuser. It does not hurt that it has a 2000 hp engine. Again the airframe was designed for the engine and vise a verse.


Props: Of course the Lycoming is designed for hydraulic prop. However the Lycoming being a huge displacement (at least for 4 jugs) big bore short stroke torquey engine can do well with fixed pitch. Well small displacement higher Revving engines NEED the RPM to achieve their power over a much broader RPM range. So if you want to have peak performance on par with a Lycoming you need a constant speed prop. This is where a very expensive electric prop comes in. Electric has it's own set of CON's: maintenance, slow response not good for aerobatics and cost. The MT electric is very expensive. Not that its not good or doable, it just is not a hydraulic prop, cheaper, less maintenance, better response and did I say cheaper.


BE DIFFERENT?
In the end do you want to be boring cookie cutter, been there done that 1000's and 1000's of times and flown millions of hours, OR do you want to be unique with a power plant creation few fly and only you can tinker with? I am in the first camp, cookie cutter engines, ie Lycoming. However I applaud those who go for the difference, which has its own rewards. To me the real call of alternative power was the call for "CHEAP POWER". That call by and large has not been the case. For one thing that has canceled the auto engine cost advantage is the proliferation of alternative engine kits that cost $30-$50K, which also takes away from the BEING DIFFERENT advantage that alternative engine builders want. To buy a FWF "alternative" engine kit is counter to being unique or alternative. However the reality is most people don't have the time, talent or resource to do a, ROLL YOUR OWN, auto installation, at least a good one. The ROLL your own is the only way to really save money with alternative engines. However than you're a slave to the "RE-DRIVE" makers, since you need to ratio down the engine RPM. Which is another thing to maintain, break and worry about. (Before you all write about how reliable reduction drives are, I know, so are transmissions in cars but they break sometimes. Helicopters fly with all kind of transmissions and gear boxes. However there have been a few close calls and one or two failures of homebuilt reduction drives. Stuff happens. If its there to break, it will. Direct drive is simple.


$$MONEY$$ & THE REAL JOY
By the time you add up the cost, money is not the advantage of Auto conversions, which was the promise in the early day of utilizing car engines. Performance and economy has been proved to NOT be an advantage auto conversions. The real joy is doing it yourself and coming up with something unique. Than the real, real, real joy is endless tinkering to improve it or make it better. My feeling is I want to FLY not TINKER. The basic Lycoming RV offers enough challenges and things to work on and improve to make me happy. I am going for engine modifications, like ignition, 4-into-1 exhaust of my own design and a few other secrets. If you want more there is HC pistons, FADEC, composite oil pans and roller cams. I am also going with airframe modifications, custom cowl, cooling plenum and oil cooler installation. At some point I want to fly and just maintain. I flew my RV-4 for almost 1000 hours and a Lycoming. It ran like a sewing machine, a loud shaking sewing machine, but also that let me go 210 mph, 190 mph on 7.5 gal/hr. To add insult to injury to the alternative engines are Lycoming and Lycoming clones which are getting cheaper!!!! With so many parts and part makers its well supported, and since the RV is designed for the Lyc, its easier and cheaper to GO WITH THE FLOW. In the end your conformity to the norm is rewarded with, less cost, less build time, better performance and efficiency. If an alternative engine guy has claim to being, lighter, faster and less fuel flow than a Lycoming I have not seen it. (Turbo charger claims are great, but lets turbo to turbo, apples to apples.) However being differnt and tinkering is its own reward. It is a personal choice. It takes all kinds to make the world go around. For those who are not crazy, we must be understanding and accepting of those brothers and sisters who are crazy.


So are you crazy?
Well some would say you are crazy to build a plane you would actually fly in the first place. Now add fly a plane with an engine you build and installed with your own unique custom installation. Now that is CARZY! I mean that in jest and think its a good crazy, but safety is premium and it requires a huge investment in time, effort and self education. Best of luck. I just don't get buying a EGG kit for more money than a Lyc, but each to their own.

WHERE ALL COUNTING ON YOU
May be your the one to come up with an optimal V6 installation with min cooling drag, cost and weight!!!!! Go for it. When you figure it all out I will gratuitously steal your ideas and may be I'll build myself a V6 RV someday, or may be I will just keep tearing up the sky's in my O360 Lyc RV-7, and when I am not flying I'll come over to your hanger and watch you tinker. I get excited sometimes about things like YEA!! THE V6. However when reality sets in, I look at the empty weight, the fuel burn vs. speed and final cost and I go, Uhaaaaa, I think I'll be cookie cutter. However I am all for experimenting and look forward to the day when someone tells me, "You see George, I told you my auto engine is lighter, faster, more efficient and cheaper to buy and install". I am still waiting. George (not crazy)

Kahuna said:

You have to remember that swinging a prop on a plane is like driving uphill, pulling a trailer, all day reguardless of the RMP. Your truck/car is pulling very low man pressures to sustain 65mph. I have personally seen subie engine internals fail multiple timeson aircraft. Usually rods.

Best,

Click to expand...

Really. Rod failures on EJ series Subarus? Please relay some details on engine type, hours etc. This is the first I've heard on anything like this on these engines that haven't been screwed with by lay people. I've been involved with Subies for 7 years. Researched all available info and fly one myself and know dozens of others flying them including the RAF gryo guys with 100,000+ flight hours and no rod failures.

So then the auto conversion is 75 pounds heavier? Hmm, maybe I could get down to the FAA average, instead of the 235 I'm at? Or instead of loading it with all sorts of radios, and fancy gizmos, I make it just a fun VFR aircraft, which is all I'm rated for anyway. It's all about compromises. So what If I carry 40 pounds of baggage instead of 80 pounds. Who the heck really carries 80 pounds of baggage anyway? I usually rent a U haul when I move! I have a 4.3 core, that I can build for $1500. Add $3500 for PSRU, another $1000 on cooling and exhaust for a total of about $7000. Yes I could by a worn out O-320 for that. Then add another $800 or so per cylinder to do a top OH. I'd still have a worn out bottom end. Yeah it would be lighter. More efficient, doubt it. To each his own. I don't mean to debate one engine versus the other. I started this post to see if there were any out there flying the engine who could offer real life experience with it. I'm not interested in the claims of those selling parts for the conversion. They usually do have high opinions of them

Some real data

RAMPEYBOY said:

I don't mean to debate one engine versus the other. I started this post to see if there were any out there flying the engine who could offer real life experience with it. I'm not interested in the claims of those selling parts for the conversion. They usually do have high opinions of them

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If you have your mind made up go for it. If it works out great. If not you can bolt on a Lycoming. I guess my point before was you are taking a little more, shall we say, risk, at least a risk in that the out come is a bit of an unknown. If I can help let me know. I have an engineering background, structural analysis.

There was an article on 10/95 in the RVator. I have a copy from the 16 years of Rvator. Jerry Schweitzer has a V6 ford RV-6 flying.

Here are the highlights:
----------------------------------------------------------------------------------

Empty wt 1130, W&B solo is within but near the fwd limit. "Our RV was the heaviest we saw at Oshkosh"
(NOTE: in 94-95 typical RV's had lighter props and panels. In the 21st century RV's have gained weight with bigger engines, c/s props and fancy panels. However 1130 is not that bad.)

Thrust line is 2.5" higher than normal.

Vert stab is displaced 1" left, no rudder needed in level flight.

Engine installation:
392 lb w/o coolant, oil, hoses or exhaust
Prop: Sensenich W71T5 H23-8- fixed wood
Engine: Ford 3.8L with "every enhancement of value for aircraft use $4200
Northwest Aero Belted re drive 1.7 to 1, 4" shaft extension $2800
Cooling: Custom radiator, surge tank, hoses, etc $375
Exhaust: from automotive pipe, no labor $17
Oil Tank: Friend welded $24
OTHER ITEMS USED BUT NOT REQUIRED:
Ellison throttle body injector $1500
Christen oil valve and fitting $227
Sensenich prop and adapter $1600


Performance:
Press Alt:.........7,500...8,000...10,000...2,000
OAT C:.............25........25........20........31
eng RPM:.........4726....4777.....4811.....5010
prop RPM:........2780....2810.....2830.....2947
MAP:...............22.......21.5......20.2......26.7
egt C:.............870......870......870........850
TCAS (mph):...175.4....173.....175.7......184
fuel flow:.........8.1.......8.1......8.0........N/A

General:
Vibration: Our Ford, except when starting and stopping, does not run more smoothly than a well maintained Lycoming. There is a narrow range where out engine exhibits a vibration somewhat like the 2100/2200 rpm range of many O320's with metal props. Settings in normal operations are quite smooth.

Reliability: 460 hours of ford flying experience, 400 in a PA-22 and 60 in the RV.

Cooling: 40 hours when surface temp was 90-105F with out cooling problems. Our cooling systems ad associated air inlets/outlets may be contributing to unnecessary drag.

A timed climb from 1000-8000' at 100 mph with outside temp around 32F calculated to 863 fpm.

LATER updated on 12/95

Changed from wood Sensenich to IVO gnd adjustable prop.
Cowl clean up, removed sharp edges in air intake opening
More efficient air entry into throttle body

TCAS (mph) at 8,000' went from 173 to 183.8 with FF went from 8.1 to 9.1 gph.
(To put this in perspective; This is about 4 mph slower than a 150hp RV-6. A 150hp RV-6 at 75% power should be around 7.5-8.4 gph. So the Ford is a few mph slower and about 1 gph more burn. If you compare to 160/180hp, their respective cruise is 191/199 mph at about the same or slightly more fuel burn.)

----------------------------------------------------------------------------------

This shows several things. One auto engines can be a continuous process of improvement and experimentation. That sounds like fun. They mention their suspicion their cooling is costing them drag. No doubt.

As far as performance its a little slower for the same fuel burn (184 mph/9.1 gph). Not good, bad or indifferent. It is what is is. Also it shows getting a good prop is a bit of hit an miss. Climb rate was not great for a RV, but that is to be expected.

Cost was almost $11,000 (in 1995). That was with a home made mild steel exhaust. No mention of engine mount modification. What was a used Lycoming in '95 going for? Also note the do it yourself spirit. Again I think when you get the real unsensationalized info you see that there is no free lunch. It takes so much HP to go so fast. Engine efficiency between one internal combustion is not much better than another. The real challenge is making a light weight installation and minimizing drag.


BOTTOM LINE: Are you going to be happy with a plane that climbs slower and cruises slower. One of the fun things to do s fly with other RV's. The circa 95 bird above would have a hard time keeping up with other RV's. Also at $11,000 and no mention of engine mount modification, plus the time to modify the cowl and so on, does a used O320 not sound a little better? I would guess a 150hp Lyc could out run this above installation and weigh much closer to 1000 lbs than 1100lbs. It is not about carrying extra baggage or gizmo's, it is about handling, stall speed and climb rate. Weight is a big factor on how "light" the control feel.

If this is not big deal than you are the guy to do an V6 conversion. Again if you need any stress analysis I might be able to crunch some number for you.

George

About the only extensive documentation of flying the 4.3 Chevs were contained in the two volumes of the Contact! "Alternative Engines" books (volumes 1 and 2). If you're thinking of doing your own conversion, I'd highly recommend these books for all the invaluable info contained within. Try http://www.pilotsbooks.com/alternative_engines.htm

These books were compiled by Mick Myal and have articles authored by many builder/ pilots who actually did their own conversions and fly them. The heartaches and triumphs are realistically protrayed.

Those are good books. I have the first volume. I think the engine, as someone else said earlier, is a solid engine, perfectly capable of aviation use. Yes there are compromises, but in the end, I believe it's safe, and can be done for less than a zero time Lycoming. Again, not meaning to make comparisons. There's nothing wrong with using a Lycoming, except shopping the classifieds for one makes me sick at my stomach! There's gotta be a cheaper way. There are several RV's flying with the 4.3 V-6, along with other homebuilts. How many have suffered failures of the powerplant (engine/prop/psru)? I don't honestly know.

RAMPEYBOY said:

Those are good books. I have the first volume. I think the engine, as someone else said earlier, is a solid engine, perfectly capable of aviation use. Yes there are compromises, but in the end, I believe it's safe, and can be done for less than a zero time Lycoming. Again, not meaning to make comparisons. There's nothing wrong with using a Lycoming, except shopping the classifieds for one makes me sick at my stomach! There's gotta be a cheaper way. There are several RV's flying with the 4.3 V-6, along with other homebuilts. How many have suffered failures of the powerplant (engine/prop/psru)? I don't honestly know.

Click to expand...

The second volume has a Velocity with a built 220hp 4.3. Very nice rad setup. He had an oil line failure due to improper heat shielding I think a few years ago but made a successful landing. I'll check my second book again to see if there are any others. Most are using FP or IVO props so not much to go wrong there and I've heard nothing bad about the two popular belt drives built in the NW. The electric props have proven to be at least as reliable as typical hydraulic props. The Yahoo E-Subie forum also takes posts from rotary and Chev V6 users but I don't see many posts there on this engine.

A few other pages which might be interesting:

http://www.vansairforce.org/articles/EP/chevy.html

http://www.prime-mover.org/Engines/GArticles/article2.html

http://www.matronics.com/archive/archive-get.cgi?RV-Archive.digest.vol-dt

http://www.northwest-aero.com/

Lots of the Lyco boys have a "feeling" that auto engines won't take it in an airplane but never produce any facts to back these "feelings" up with. What follows in the test that GM puts their engines through:

Refrigeration unit pumps 0F coolant into engine. Thermocouples tell engineers that core of block has reached 0F. Engine started and taken to WOT immediately and near full power rpm (4400 rpm). 11 minutes later, coolant temp is 260F. Engine is shut down. Immediately hot coolant is drained and 0F coolant is pumped into hot engine. When core temp drops to 0F, engine is started and flogged again etc. They do this between 150 and 1600 cycles on the same engine mainly to check for head gasket integrity but this will obviously uncover other things from time to time.

One powertrain test is done on a dyno with transmission hooked up. A variety of programmed tests are done including up to 1200 hours of redline shifts going through the gears up and back down, plus WOT and redline rpm held for 5 minutes.
Lexus runs their engines for 400 hours at WOT and redline on the dyno. Most manufacturers have similar or worse tests to validate their engine designs.

I have a "feeling" that no Lyco would pass the first GM test mentioned.



I say go ahead with your dream and forget the naysayers.

Guys I appreciate the links, and other information. I'm getting quite an education from this topic. Thanks again.

Not another topic as auto vs. Lyco generates so much passion and debate. As you said earlier, you don't want to compare or debate, just get some facts from 4.3 users.

I dug out some more info here which might be interesting:

Jess Meyers' article in AE2 states FF weight at 385 lbs., about 45 lbs. heavier than the O-360. Base longblock only was 282 lbs. This is with cast iron heads. They feel that the aluminum heads would get the engine closer in weight and of course the aluminum block would shave even more off. Depending on prop used, the engine could be competitive in weight with a Lyco. They used a 13 lb. 3 blade Warp drive.

They run the engine between about 3200 and 4500 rpm in flight.

Their RV6A weighed 1154 empty. I think Kitplanes featured this aircraft in a test flight article a few years back also. Can't locate my issue howver.

Stan Pitts describes a 4.3 builup and dyno run. He limits the engine to 4800 rpm where it made 219 hp and 240 ft./lbs. of torque. BSFC ranged from .39 at 2800-3100 to .49 at 4000 rpm.

Tim England flies the Velocity. 220hp on the dyno at 4500 rpm which is his max flight rpm.

More info on the PV6 GM engine and durability tests:

They run 13,000 shift cycles at 6200 rpm shift points with the engine braking the dyno down after each cycle to start the next one at WOT. They also ran the engine for 265 hours at WOT and 6200 rpm continuously and another test of 400 hours at between 4400 and 6200 rpm again WOT plus a 2000 hour idle test for oil pressure/ lubrication studies.

Might be a suitable choice for the -9 with the aluminum goodies. They do fly better light!

Thanks!

Thanks for the replies and informative data from everyone!

MUCH appreciated.

Gary, have a look at the Belted Air Power web site. There's a RV-9A on the home page with one of there PSRU's. There no further info as to which engine, but I'm guessing it's the 4.3 since BAP has been promoting it's FWF for RV's using the 4.3. Maybe the owner is a reader on this site....