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Tom Martin
12-26-2015, 05:39 PM
On December 24 the skies and winds allowed me to achieve a ground speed of 270 knots at 4500 feet. I have made this speed a couple of times above 15k but never this low.

http://i65.tinypic.com/a4ymno.jpg

I just recently had my engine rebuilt and with about 5 hours on it I am working it hard. Note the TAS of 220 knots cost me 22gph running full rich!

With just a bit over 900 hours on the engine I had to have it rebuilt. I have replaced my ECI cylinders, 10:1 pistons/Lycon port and polish, with stock Lycoming cylinders and pistons.

It is too early to tell how much speed I have lost at the top end; I am guessing 5 knots. What will be interesting is to compare my cruise settings of 22 squared, but that will have to wait for another 5 or 10 hours.


Blow by from the breather tube is almost non existent and I thought that on todays flight that the oil and cylinder temps were down a bit, under 180 OT and 380CHT.

I am looking forward to a more trouble free engine!!!!

hydroguy2
12-26-2015, 06:16 PM
Excellent...well except burning all that fuel.
It will be interesting to see your cruise numbers compared and also how you do in the SARL races.

Tom Martin
12-27-2015, 06:18 AM
Brian
I retired the plane from racing three years ago. Straight and level speeds were getting too fast for my comfort level. The good news is that it has made this airplane a great traveling vehicle for my wife and I. Typically I flight plan 210 knots at 10k,burning 11gph. This is the number that I am curious about; what will it be now with a stock engine setup?

gstone
12-27-2015, 06:30 AM
Very impressive, as always!!
greg

hydroguy2
12-27-2015, 08:34 AM
Brian
I retired the plane from racing three years ago. Straight and level speeds were getting too fast for my comfort level. The good news is that it has made this airplane a great traveling vehicle for my wife and I. Typically I flight plan 210 knots at 10k,burning 11gph. This is the number that I am curious about; what will it be now with a stock engine setup?

I understand that decision. I haven't raced for a couple years. I enjoyed it and the people, but after dodging some seagulls at 185kts and 200'agl I had to rethink it. Also between building a house and my Dam work, I don't fly many hours these days. I still like to go fast up high and occasionally down low over the ice.

210kts...great traveling machine for sure.

rvmills
12-27-2015, 10:26 AM
Very nice Tom! It will be interesting to see what 22^ looks like. What were your indications that called for the re-build? Always on the lookout here too!

Any new projects in the Fairlea Farms Skunkworks this winter?

Cheers,
Bob

Toobuilder
12-27-2015, 10:31 AM
210 @ 11 is pretty impressive. I've been cleaning up my airplane but my new flight plan numbers of 200 @ 12 show I have a long way to go. I do have a bone stock, factory built 260 though. Will be curious to see what a change your cylinders does to you.

vlittle
12-27-2015, 10:49 AM
210 @ 11 is pretty impressive. I've been cleaning up my airplane but my new flight plan numbers of 200 @ 12 show I have a long way to go. I do have a bone stock, factory built 260 though. Will be curious to see what a change your cylinders does to you.

I have similar results. Tom's Rocket is an F1 EVO which is intrinsically faster, especially at higher altitudes. I've incorporated many of Tom's speed mods and got my 8500' top speed to 208 knots. That extra few knots was a lot of work, but hardly worth the time and effort unless you like the challenge.

I like to cruise at low altitudes about 180-190 knots at about 17-18 nautical miles per US gallon (about 0.049 furlongs/cm^3).

Tom Martin
12-27-2015, 11:02 AM
Bob here is the short story on the engine

First flight 2006, nickel carbide ECI, 10:1

2010, 400 hours cylinders back for recall, four new, two rebuilt, rings delaminated, needed new pistons
shipped to Lycon for port and polish, 10:1

2013, cylinders removed,honed, valves lapped, high oil, blow by, rings delaminated. Cam and lifters looked good.

2014, 50 hours, cylinders NEVER broke in, high oil consumption, some metal in filter noted. Pulled one jug and found lifters badly spalled!

Engine back to shop and torn down. Noted excessive main bearing wear

And thus a big bill for repairs but now I have brand new Lycoming jugs and stock pistons. Although I did a few races with this engine the total hours of racing would have been less then 20 out of 900 hours. I always fly cross country at 60 to 65% power. I had hoped for 1500 hours in the engine using 10:1 but that was not my experience. As for the spalled lifters in 50 hours I can only imagine that all that excessive blow by into the crack case caused a swirling of grit that started the wear process.

The new rebuild it running very well with almost 6 hours so far. Oil use is normal for a rebuild but this time there is virtually no oil on the belly and that is a huge change from the last 900 hours. Especially since I have been running in the 80 to 95% range for those six hours. Temperatures are good as the OAT are cool at this time, around 0-5C. I have a feeling that the last half hour the temps were falling a bit. Maximum seen so far was 410 on #6 and oil of 195. Currently 380 and 180 at 85% power, full rich.
I feel comfortable leaving the patch now and all I need is some good weather to add to the hours. I would like another few hours at these power settings before I do any leaning. That is when I will know how much power I have lost, right now I am thinking less then 5 knots at the top end.
Fuel economy will be another factor. Heck if these jugs break in properly they might do as well as the ECI cylinders that always had higher oil consumption...

Tom Martin
12-27-2015, 11:06 AM
Bob
Sorry, missed your other question! Yes I have an RV14 in the shop. The metal work is almost complete and it has passed our final pre-closure inspection. I kind of ran out of enthusiasm when I found out the cost of the finishing kit! This is just a keep busy project and it will likely be sold sometime in the spring.
The RV14 will be an awesome airplane but I am not yet old enough to need to go 40 knots slower then the rocket :-)

smokyray
01-04-2016, 08:39 AM
Bob
Sorry, missed your other question! Yes I have an RV14 in the shop. The metal work is almost complete and it has passed our final pre-closure inspection. I kind of ran out of enthusiasm when I found out the cost of the finishing kit! This is just a keep busy project and it will likely be sold sometime in the spring.
The RV14 will be an awesome airplane but I am not yet old enough to need to go 40 knots slower then the rocket :-)

Hi Tom,
Always great to hear of your adventures. 270 Knots over terra firma in a piston powered Kitplane is hauling the mail for sure. Very cool. I miss my HR2 and seem to spend more time working these days than ever, New Years included. Maybe one of your former HR's will come up for sale sometime...:)
I remembered your post and thought I would share a screen shot I took recently. I know it's a commercial jet (B737-800) with 175 witnesses along for the ride, but I thought it was worth sharing. Note the winds: Jet stream was howling that day!
V/R
Smokey
http://s11.postimg.org/ku0ap9rtf/629_Page_1.jpg (http://postimg.org/image/p350rfv2n/full/)