Smooth bottom cowl system???

[cawmd82]

Several RV8s have been seen lately with a smooth bottom cowl and no snorkel:
One example....several others seen on here lately.......
http://picasaweb.google.com/VansAirF...53987192232914

Which induction system(s) work this way?

Any major disadvantages/advantages besides the clean look?

Exactly how does the air intake get plumbed?

[aparchment]

Chuck:

I want this "smooth" cowl for my 7A as well. My understanding is that I have to go with the horizontal induction engine. The consequence of this is that the engine intakes air from one of the front cowl intakes. As a result, you probably lose any ram air benefit that would be had from a more forward facing intake like the snorkel (or Checkoway's modified forward intake). In addition, the twists in the inlet duct to take the air from the cowl intake to the engine intake most likely further reduce the velocity of the incoming air. Finally from what I have heard the ability of the engine to intake air during steep angles of attack is impaired if you use intake air from the cowl intakes rather than the snorkel.

I hope one of the experts in this area chime in to either correct or corroborate what I have said.

[Kahuna]

Chuck I believe you are confused.
The smooth bottom cowl has no "scoop" but I guarantee you it has the snorkel.

[cawmd82]

Look at the picture of the yellow RV8 in the first post.

Where is the air intake? Several others like this have been seen on here in the last few months, in particular a polished and red P51 looking -8 a month or 2 ago.

[jferraro17]

Chuck-

The "snorkel" refers to the fiberglass tubing that takes the air from the left intake ramp down to a horizontal induction.

The "scoop" is for a vertical induction system, FAB, etc.

To go smooth, you need a snorkel...and from what I understand, most likely FI.

Joe

[pazmanyflyer]

Originally Posted by cawmd82

Look at the picture of the yellow RV8 in the first post.

Where is the air intake? Several others like this have been seen on here in the last few months, in particular a polished and red P51 looking -8 a month or 2 ago.

See picture 6 and 7. http://www.rvproject.com/20031226.html This is Dan's setup and all I've seen are located in the left inlet on the bottom baffle.

[David-aviator]

Originally Posted by pazmanyflyer

See picture 6 and 7. http://www.rvproject.com/20031226.html This is Dan's setup and all I've seen are located in the left inlet on the bottom baffle.

Here is another very detailed write up on Dan Checkoway's ram air system.

http://www.rvproject.com/20050426.html

[DarylT]

Chuck

To use the smooth bottom cowl you need to have an engine equiped with horizontal induction. The intake on Dan's cowl was a modification done for ram air. If you have this type of setup you do not have to go with the ram air mod. The yellow RV8 you show in the pic for example is not using ram air. The air gets picked up thru a FAB snorkle under the cowling. The air comes in thru the the top of the snorkle that terminates at the baffle in the left intake.

[Rockyjs]

This is the setup on my Superior IO-360 Horizontal cold air induction. The paper towels are covering the K&N filter in the snorkel. The fit of the FAB was poor as I had interference with the Plane Power Alternator bracket and also the starter solenoid. I attempted to heat the fiberglass and make a bend, but couldn't get enough clearance. Eventually the FAB was cut and new fiberglass was layed up to provide clearance.

[cawmd82]

So it looks really slick-all will agree to that I expect. What other advantages-disadvantages are there? Is it just another way to skin the cat?

Any effect on the cooling process?