sgtshultz

My Feedback: (28)

I have an RCGF 40cc twin. Nice engine. But needs either an air intake manifold or ????

Recommendations?

thanks

scott

pe reivers

sgtshultz

My Feedback: (28)

I'm not sure what this tells me.

pe reivers

Not sure what you asked either.
The picture tells you all the parts that should be in there.

sgtshultz

My Feedback: (28)

I am asking what air intake manifold is recommended

They do not come with the engine.

pe reivers

The manifold is the part between carburetor and engine. For carb trumpet/air intake, use whatever suits your taste.

sgtshultz

My Feedback: (28)

I was going by what 3W calls theirs.

kmeyers

Planes don't always need "Velocity Stacks" but they rarely hurt you. Here is a link to TH.

http://www3.towerhobbies.com/cgi-bin...?&I=LXJ775&P=7

pe reivers

Ken,
This guy is a moron!

Tony Hallo

That what's I allways thought until I came across this somewhere here or there. The most common shapes have a negative impact

dant-RCU

My Feedback: (3)

+1 to Pe's last reply.

Dan

kmeyers

Huh? What does that chart mean? What test was being done?
Thanks
I forgot to mention that Velocity Stacks look way cool which overcomes any negative impact!

dadragon

Velocity stacks work,not just for looks because they are functional,they stop the fuel from spitting out the carb intake end,my 40 twin is a 90 degree off the carb 12" back into the fuse witch the last 5" opens from 1 1/8" to 3" to form a ram effect and totally retune the carb.I have done with a 100cc first and it worked so well so i thought a 40 mite do as well and it did.this from drawing air from the inside,I have not tried this from the outside airflow but stacks do help.SGT for your info YES stacks do work.

skip1320

Wow are we gonna see wind tunnel test,s inside of fuse,s now? hatch on or hatch off,who knows?

Tony Hallo

I think the chart speaks for itself, change in airflow vs. shape. I believe shape four is one of the more common shapes in RC and offers 5.5% lost compared to a bare carb. I like my carbs inside the cowl I really don't care what they look like. If you Google Ram Pipe you will find that most have the radius on the end that provides increased performance. I find shape 11 interesting.

pe reivers

The most efficient in the chart is #11
This can be further improved upon by introducing a raised circular part around the contraption, as was/is used in Webra and MVVS carbs.

dadragon

I build warbirds there is no tunnel testing or hatches to take on or off the air scopes for the carbs and oil coolers intakes on these planes are used just like the full scale is all I try to do and they breath just fine without dumping gas IN the fuse.

sgtshultz

My Feedback: (28)

Can you post a pic of yours?

cuwaert

Usually we bolt the engine to the fire wall and connect everything.
Mostly it works good, sometimes it doesn't.
We are not aware of what air moves around the carb and fuel line. Is it warm or cold, steady or turbulent.
Before worrying about velocity stacks one should make sure fresh outside steady air is present around the carb.
To do this isolate carb compartment from engine/muffler compartment.
Make a fresh air intake to the carb compartment to ventilate it with.
Now is the time to think about velocity stacks.