R

rv72004

Well Known Member
I cant seem to find info on the angle valve equipped IO390 RV8.
I am looking for info and or links to the ;
1] flight characteristics with the heavier motor
2] real world performance gain and advantages

Also there seems to be 2 ways a 390 comes to be;
- longer stroke "Mattituck"
- bigger bore "BPE"
Which is better??

Thanks
 
The third option

You are forgetting the third option, Lycoming.

I have installed the BPA in a -7a and it really didn't fit well. I have installed the Aerosport power (same kit as the mattituck?) in a 7a as well with much better results.

AND NOW I have a Lycoming IO-390 with the rear mounted governor and it fits perfect.

I also have improved the air intake as I like the Rocket looking intake so you can see the one I made molds for on my web site

www.blueskyaviation.net

I also came up with a remote oil cooler and duct work but you have to have the Light speed ignition, rater the lack of a mag on one side or the other.
 
BPE

I have the Barrett built engine in my RV-8, went with the lighter 3 blade CB MT prop. Performance is outstanding! Allen Barrett even drove up from Tulsa for our first engine run. There are also 2 more Barrett 390s' here in the KC area, the other 2 are on RV-7s'.
 
Noel,
<<I also have improved the air intake as I like the Rocket looking intake so you can see the one I made molds for on my web site>>

How do you accomodate engine movement, and do you have any filter drop numbers for it?

EJ...usual rules apply. It will climb faster, but won't go a lot faster when level. Yeehaa stuff aside, you get 200+ hp with relatively low compression, so it should swallow any future fuel we're likely to see.

<<I have the Barrett built engine in my RV-8..>>

Me too. They invented and developed the thing. Why go elsewhere?
 
I have a IO-390 RV8. I haven't been able to fully test the performance due to a foot operation. I think you can count on some increased speed assuming you run the engine at the same relative power setting. And as mentioned in an earlier post, biggest gain is in climb.

As you know the engine is a little heavier than an IO-360 200hp engine (8-10 lbs). RV8 handling is somewhat sensitive to cg location and weight. I have a heavier extended hub Hartzell prop because I used a James cowl. I carry rear ballast when flying alone for better landing handling.

There is really only one configuration IO-390X even thought you can get it built by several different folks. They all pretty much use the same set of Lycoming parts. The engine is based on a IO-360 angle valve case bored to accept the Lycoming 580 cylinders. They have a bigger bore but same stroke, thus the 390 cubes. Otherwise the engine is pretty much the same as a front governor drive IO-360 angle valve 200hp engine with the exception of various FI and ignition systems.

It is true that BPE developed the engine, but then Lycoming liked it and went ahead and offered a full config for the engine. They just certified the engine and its being offered for some engine upgrades on certified aircraft.

My engine came from Mattituck and uses the same Lycoming parts. You can get the engine (experimental version) also directly from Lycoming.
 
Dan, does the forward CG cause negative handling characteristics with the extra weight ?
I want the extra power and maybe a parallel valve IO375 is the ticket.
I will get some extra hp at the same weight.
 
DanH said:
Noel,
<<I also have improved the air intake as I like the Rocket looking intake so you can see the one I made molds for on my web site>>

How do you accomodate engine movement, and do you have any filter drop numbers for it?

I am using the Van's supplied K$N and deal with movement by a small piece of SCAT tubing between the filter housing and the engine intake.
Click to expand...
 
IO-390 in RV8A

signed off on 7-9-09 by FAA, now have 49 hours on it
Perfect for the RV8 with Hartzell airblended prop, seeing top speed near 240mph

fits like a glove in cowling, tightest spot only 1/4" clearence, eveything runs cool as a cucumber
mg
 
mikeg said:
signed off on 7-9-09 by FAA, now have 49 hours on it
Perfect for the RV8 with Hartzell airblended prop, seeing top speed near 240mph

fits like a glove in cowling, tightest spot only 1/4" clearence, eveything runs cool as a cucumber
mg
Click to expand...

What about the Vne of 200kts of the RV-8? Doesn't speed like that invite compromise of structural integrity? Just curious.
 
OK.....

With that avatar you need to ask this question? Seriously 200 knots equals 230 mph. 240 mph is only 4 per cent above. These airframes are supposedly tested to 10 per cent above. Note the word "near" . So now we're somewhat less than the 4 per cent, Fishing stories aside about the 240 mph. Speed is good. Just crunching numbers.
 
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Well, since I just finished the Texoma 100 Air Race, I can give some real numbers measured by others.

My race speed for the course was measured at 197 kts or 227 mph (using ~28" MP and 2700 rpm). Of course this happened in a fairly high wind/turbulent day and thus reflects average GS. I saw about 190 to 200 kts indicated at a fairly low altitude (500-1000 msl) on a cool day.

Unfortunately, it was so bumpy, I didn't record a lot of good data.

My speed in the earlier Taylor 150 was 190 kts and reflects a less than good run due to my navigation and turns.

You would have to be diving to get 240 mph top speed out of my ship...
 
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