aeroflyer

Going to be setting up a ZDZ 160 with cannisters my question is can you shorten the header length to improve performance ,I have never used this type of setup B 4. I have experience with single cyl. gas engs between 23 and 62 cc. I am gathering info now as this will be a fall and winter project. Thanks in advance.

Paul

Lew

It depends on the type of cans you are using. I'm using JMB's from RCShowcase and they are not tuned. I still injoyed a couple hundred rpm's increase with these, and no tuning required. Check with the manufacturer of each can for the process they recommend, if tuning is required, before you buy. I really like mine and they were very simple to install.

Lew

JB Rekit

My Feedback: (3)

yes, you can pick up top end RPM by shortening the header, but you will lose you midrange if you make it too short trying to get a little more out of the top.

I wouldn't worry about not having enough power with the 160 (guess it depends on what plane you get, but if it is under 41-42#'s I would worry about it.
I am using a DA 150 with the KS 120cc cans and an AM 28x12 prop 6000 rpm on a 39# extra and it isn't hurting for power.

If you want a little more thrust, you could always go with a 2 blade.

just my $.02

John

aeroflyer

Thanks Lew and J B I will be putting it in a Lanier 40% edge and to start withI should probably leave it at full length?

rmh

These JMB muffler cans run best quite short - they not like any others I have tested -they are not at all like the KS tuned cans.
The header can be 6" or less.
We have run all the sizes About the only notable thing is that the small 60 cans run well on the 40 and 50 -- the 70mm cans on the 50/60 cc engines. the 70mm and 80mm on the 80cc . (160cc)
The 210 has some very free flowing cans - specifically for it.

aeroflyer

Thanks Dick. Now one more ? From where on the header do I measure , at the point of contact with the cylinder or someplace else. Thanks again , Paul

JB Rekit

My Feedback: (3)

Have you heard about anyone using the JMB's on a DA 100 and what length were they using on their headers?
I've been meaning to put some cans on my 100 for some time now and it would be great if I could use a shorter header than what I use on my KS cans b/c it would save me from having to cut through my 2nd former which would turn it into a very quick install. Whatever I do I need to get the plane back in the air b.c. I know I will need a backup plane this year. Mine always like to have things go wrong right before and during the IMAC season/ contest I think I may make it my beat around freestyle plane.

thanks

John

rmh

I can't imagine that they would not work just fine -but
I have not run them on a DA100- so I have no hands on data.
The measurement?
never bothered - just place em as close as conveniently possible -typically, we add the 90 degree curve to the exhaust flange - then an inch or so of straight tubing. (K&S header kits)

I assemble the can/and header parts -right on the engine- tack weld everything in position then remove and finish brazing
the engine does not get hot - Although you can purchase assembled headers, -some installations simply do not fit up as required -
When completed, the rear of the can should be supported in a 1/2" long isolater made from silicone exhaust tube ( Aerotrend 3/8" i d )
the front is just supported by the Teflon coupler and the two spring clamps.
for a DA100- I would use the 70x300mm size cans -they are about 300 mm long.
On some installations, I use 1" id Aerotrend cream couplers at the front - these do not burn out if the system is all aligned properly.
This setup has no vibes transferred from engine to can and is very quiet.

JB Rekit

My Feedback: (3)

Thanks

I think DA sells those cans now, I'll just ask dave what length header he seems to like best on it and go from there.

Thats the same technique I used on the ZDZ 80 header pipe with the tuned KS pipe. Worked out well. I think I'll probably just get Dave to send me whatever size header he thinks is appropriate b/c I have all sorts of vertical and horizontal room, I'll just have to uncover the bottom of the fuse to cut my second former if its going to go back that far.

John