James cowling help??

[Bill Whidden]

I am ordering the Sam James cowl and plenum for the rv6. I want to put the Air flow Performance FI system on also. I was actually on a 3 way call with Don from AFP and Will from James Cowl and am still not sure if we were all on the same page. So I thought I would ask, .. Has anyone else used this combination and if so how did it work. I also have the cross over exhaust. Which AFP system was used ??and which cowl was ordered?? are the two real questions.

Bill
RV-6 someday.

[Bill Whidden]

This is for a 360 lycoming.

[Highflight]

I know you're looking for actual experience, Bill, but I'm in the process of deciding and ordering so here's what I found out and did:

My engine: Mattituck IO-360 w/Airflow Performance Injection and two P-mags.

I talked at length with Will James this morning and the short story is that if you want to truly get the benefit of the James cowl, you want to go with the extended cowl and not the standard length cowl.

The reason, according to Will James, is that the benefits of the James cowl come from the improved aerodynamics of the extended cowl over the standard length James cowl, the "new and improved" induction system made for and supplied with the extended cowl, and of course, the airtight plenum with round inlets that maximize air flow and cooling with less drag.

The better aerodynamics, he says, comes from the extended cowl. Plus, the improved induction system only comes with the extended cowl and not the standard cowl. You could use just the SJ plenum with the standard Van's cowl, but you won't get the benefit of the SJ plenum due to the less than optimum square openings in the Van's cowl.

The other side of that coin is that if you use the extended length SJ cowl, you will have to use a 4" prop extension if you use a fixed pitch prop (like me), or a 2-1/4" prop extension if you go with the Hartzell CS prop. I don't personally think either case is a problem while others may disagree.

I can't definitively say about the exhaust, but I don't think it makes any difference which cowl you use.

The only little "gotcha" you want to know about is that the Airflow Performance FI uses a purge valve. I contacted Don Rivera at AFP this morning concerning using the AFP system with a Sam James Plenum and here's his response cut n' pasted from his email:

"Yes. If you use a Sammy James pressure cowl, please make sure you order the fuel injection kit with a "horizontal mount purge valve assy". This comes as an assembly with the flow divider and purge valve attached with appropriate brackets. The rotation of the purge valve is also reverse from the standard set up."

Hope that helps.

[gmcjetpilot]

Bill you are in luck. Go to the Yahoo group: http://groups.yahoo.com/group/JamesAircraft/


You can join to post. Be sure to check out file and photo links. There was a great write up with pictures and discription of a FI fwd facing set up. I think it was in a post in the last 2 weeks. There was a link to a builder web site.

I would join and post. George

[RV7Factory]

Originally Posted by Highflight

The other side of that coin is that if you use the extended length SJ cowl, you will have to use a 4" prop extension if you use a fixed pitch prop (like me), or a 2-1/4" prop extension if you go with the Hartzell CS prop.

I recall talking this over with another builder, but can't remember the #'s... this reduces the g-limits of the aircraft somewhat doesn't it? If so, anyone know what the new limits are for the CS?

[Kyle Boatright]

Many moons ago I read a thread on the RV-list where the only prop that was compatable with the SJ cowl was a Mooney (?) prop that has a recommended G limit under 4...

By now, the cowl may have evolved to accept other props, or one of the new prop offerings might fit. Can't say.

I'd ask the cowl vendor to be sure.

KB

[gmcjetpilot]

Originally Posted by Kyle Boatright

By now, the cowl may have evolved to accept other props, or one of the new prop offerings might fit. Can't say.

I'd ask the cowl vendor to be sure.

KB

Yes I don't think it is wise to add an extension on a constant speed prop. The "extended" hub props are more expensive, more rare and the g-limit is about 3.8 g's. All acro should be done at 3 g's any way, but all true.

Yes there are no extended hub props for 200hp IO-360 users, so this produces a little problem, and thus why folks are tempted to add extensions to constant speed props.

Yes SJ is in the process of making "short" cowls so the standard HC-C2YK or HC-C2YR can be used. He has not finished this and who knows when.

Again my solution is using Vans stock cowl and modifying it.

G

[Bill Whidden]

Any reason this set up won't work.

0-360 being converted to API's FI. The project I bought has a rebuilt pressure carb. What to do now with bendix pressure carb?


Buying SJ cowl and plenum. Don't really have a good reason except they claim 7-10 mph increase over the vans one I have now.

Changing out slick mags for 1 e-mag and 1 p-mag.

Getting 4" prop ext. from Saber Manufacturing so my fixed pitched sensenich will fit the new longer cowl.

Have a single egt guage. Should I change to 4-way egt being I now have fuel injection?

Anyone want to come vacation in Sunny Warm Florida for a couple of weeks to get out of the frigid north and help me put all of this stuff together??? Have spare room and car.

Bill Whidden

[osxuser]

The Mooney (M20J) prop IS for a 200HP IO-360 (A3F6) as installed on the M20J.

[jclark]

Originally Posted by Bill Whidden

Any reason this set up won't work.

0-360 being converted to API's FI. The project I bought has a rebuilt pressure carb. What to do now with bendix pressure carb?


Buying SJ cowl and plenum. Don't really have a good reason except they claim 7-10 mph increase over the vans one I have now.

Changing out slick mags for 1 e-mag and 1 p-mag.

Getting 4" prop ext. from Saber Manufacturing so my fixed pitched sensenich will fit the new longer cowl.

<SNIP>


Bill Whidden

Just curious ...

Will the AFP FI setup fit in the "standard" Van's cowl that is normally used with a carburetor?

James