|
-
POSTING RULES

-
Donate yearly (please).
-
Advertise in here!
-
Today's Posts
|
Insert Pics
|

05-10-2008, 05:49 PM
|
|
|
|
Join Date: May 2008
Location: Logandale NV
Posts: 45
|
|
Sam James Cowl
I've been looking at different websites and there seem to be deferent views(as usual) on the Sam James cowl being worth the effort. Vans doesn't recommend doing anything but build the stock plan. I assume if I do the baffles correctly cylinders will stay cool. I have also been told by other builders that any time you make a small change in the plan or add something it always effects other stuff in the kit and takes tons more time than you think it will. I have to admit the cowl looks nice!
Alan
|

05-10-2008, 08:26 PM
|
 |
|
|
Join Date: Jul 2005
Location: Detroit, MI
Posts: 1,587
|
|
I would do it again
Your post seems to be a request for feedback. Yes, it may cause more work, but in the case of the cowl, not much IMHO. If you go with the cowl, go with the plenum, too. I believe it's a drag saver and that it improves cooling. I won't take the space to argue it here, but I firmly believe it's true, Van's NIH reaction notwithstanding. James is not the only one to use that style cowl (LoPresti is another).
__________________
H. Evan's RV-7A N17HH 240+ hours
"We can lift ourselves out of ignorance, we can find ourselves as creatures of excellence and intelligence and skill. We can be free! We can learn to fly!" -J.L. Seagull
Paid $25.00 "dues" net of PayPal cost for 2015, 2016, 2017 and 2018 (December).
This airplane is for sale: see website. my website
|

05-10-2008, 08:43 PM
|
 |
VAF Moderator / Line Boy
|
|
Join Date: Jan 2005
Location: Dayton, NV
Posts: 12,256
|
|
I like it....but...
Since you asked specifically about an -8 (which is different than a -7), if I recall correctly, when I was building, the Sam James cowl for the -8 required you to have a prop extension. I never read enough convincing data that showed me that the prop extension on a Hartzell C/S prop was fully endorsed for aerobatics, and this was a show stopper for me.
Now that was over three years ago, and it is possible that the Sam James folks have reworked their design, in which case - yeah, I think the round inlets look very cool! But from the accounts I have read, you WILL spend more time building the cowl than if you went stock van's.
Paul
__________________
Paul F. Dye
Editor at Large - KITPLANES Magazine
RV-8 - N188PD - "Valkyrie"
RV-6 (By Marriage) - N164MS - "Mikey"
RV-3B - N13PL - "Tsamsiyu"
A&P, EAA Tech Counselor/Flight Advisor
Dayton Valley Airpark (A34)
http://Ironflight.com
|

05-10-2008, 09:09 PM
|
|
|
|
Join Date: May 2008
Location: Logandale NV
Posts: 45
|
|
Aerobatics
Paul
A guy in chino has an extension on his 8 and he told me it has limited his aerobatics. This could be a deal killer 
|

05-10-2008, 09:12 PM
|
 |
|
|
Join Date: Oct 2005
Location: South Hamilton, MA
Posts: 521
|
|
a few more considerations
I considered the James cowl for my 7A, but finally decided against it when I heard that the prop extension would limit the g-loads the plane should experience. I would like to fly aerobatics, so that was a negative factor. I also didn't want to deal with the fab that would be required to fit an injected IO360 with forward facing induction into the cowl WITHOUT using the snorkel. I just don't like the look of the snorkel.
I think the cowl and plenum are great ideas if you don't have either of my limitations.
The advantages are supposed to be better cooling, less drag/more speed and arguably a more modern look.
__________________
Antony
RV-7A
Empenage complete, wings complete, tip-up canopy complete, starting wiring ...
|

05-11-2008, 07:05 AM
|
 |
moderator
|
|
Join Date: Dec 2004
Location: Mill Creek, WA
Posts: 617
|
|
"Is it worth it?" is a question that can only be answered when one knows your particular priorities. I did it on my RV-8 and in retrospect, and with all things considered, would not do it again. When I built my second RV I went with the stock cowl.
Not sure if you've seen it or not as you've done your research, but here's a fairly thorough account of my experience...
http://www.romeolima.com/RV8/Cowl.htm
I got by without the prop extension. If I had had to use the extension then there would have been no way, that is a deal killer for me from the get go.
__________________
Randy Lervold
RV-12iS, empennage/tailcone complete, wings currently, fuse in box
RV-3B, first flight 2007 - sold
RV-8, first flight 2001 - sold
|

05-11-2008, 07:40 AM
|
 |
|
|
Join Date: Feb 2005
Posts: 1,082
|
|
Retrofitting with Van Cowl
I just received my SJ plenum and will install it using my finished and flying RV7 with its stock cowling. It will take some major reworking of the front to fit the inlets in but I'm up for the challenge. A little extra speed and better cooling is what drove my decision to try this and it will allow me to gauge the performance increases from stock to using the plenum. I'll keep everyone posted on the numbers once the work is done which I am pushing to finish to fly it done to Oshkosh.
__________________
Mike
JAMES AIRCRAFT.com
Flying - RV8 Hot Rod "Drone Killer"
Flying - RV8 "Look'n Good"
RV4 - FAST & FUN! Rebuilt, Flown, Sold
RV-7A Built, Flown, Sold
|

05-11-2008, 08:29 AM
|
 |
|
|
Join Date: Jul 2006
Location: Corvallis Oregon
Posts: 3,547
|
|
Works for me
I have a 2.25" prop extension and a Hartzell C/s prop.
Do I fly aerobatics...Er yeah actually I do..
http://youtube.com/user/frankhinde
Now having said that...The RV is not a rip snorting aerobatic airplane, I avoid gyroscopic manouvers (I.e adding high power to aggravate spins etc) but the RV is just not that sort of airplane if you see what I mean.
I have close to 300 hours on this set up.
I also started a Yahoogroup to gather all the builders in one spot and there is a lot of good info there now.
http://groups.yahoo.com/group/JamesAircraft/
Would I do it again?..Look at the beautiful airplane at the front of the yahoo group..You tell me?..
Frank
|

05-11-2008, 08:56 AM
|
 |
|
|
Join Date: Feb 2007
Location: Fresno, CA
Posts: 321
|
|
Another opinion
I opted to go half way. I've got the Sam James plenum but only added the SJ rings to the stock cowl, so no prop extention required. I love the looks of the resulting cowl. I also love the performance. I am regularly running down 200 horse 6's and 7's. My XP-360 is only supposed to be 180 horses, but the combination I've got seems faster than stock.
Would I do it again...yes just like last time, only it wouldn't take as long because I no longer fear ripping into perfectly good fiberglass pieces.
__________________
Timothy Cone
Sierra Skypark (KE79) Fresno CA
RV-8, XP360, RV200
Flown Sept. 12, 2007
1600 hours on the hobbs and loving it
|

05-11-2008, 09:14 AM
|
|
|
|
Join Date: May 2008
Location: Logandale NV
Posts: 45
|
|
Why I posted
Randy,
Your website and experience is one of the reasons I posted this thread. So the plenum can be retro fitted to the stock cowl. Are is there any pics put there? Speed is always attractive but I'm wondering more about cooling. I live in the desert. That is why I'm asking the question
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -6. The time now is 07:36 AM.
|