rmh

You should be able to run 40-1 Pennzs to stroke air cooled.
Any reason you went to the 25-1 mix?
Once you have the running at WOT stabilized - try a good syn oil-
The 40 does not carbon badly on pennzs -I ran first one quite a bit on it but the Redline does run a little faster starts a little easier -etc..
Let's see pylon controline--
Mc Coy ? Dooling? Hassad?

rmh

run a 1000 ma NiCad for best ignition.
The 270 poops real fast.
Makes engine seem to go rich - actually just poor spark

Scorpionjack

Dick;
Thanks I am running a 1400 in the Aircraft these were just for break-in. The 25:1 was Penzoil for the fir 3:45 hours Now I cleaned everything and changed to 40:1 Klotz brand 2 Stroke Synthetic as I had a spare pint in the shop. Then let the 270Ma pack run which took about 30 min. to deplete to what you say is a rich setting : ) 4.5 hrs took right at 2 gal give or take a pint running at 4000 Rpm and then releasing to Idle and going to High for a little then backing off to 4000 again.


Pylon Control Line? LOL you remember Monoline Racing, Rat Race and Proto speed?
Fastfill and a Hot Glove for starting.? Those were good days. Perfect Tanks, Veco Tanks and Veco Speed wheels? I think I still have about 20 sets of those some still in the boxes.

Well anyhow thanks Dick

Iflyrc4fun

My Feedback: (132)

Hi All,

I just wanted to say thanks for all who answered my original post on the ZDZ 40 props. i found your information very helpful. I am running the 20-10 Bambula now. I think I will try a Meijeck and Pro Zinger 20-10 and 22-8 for comparison. It might take me a while but I will post the results to you when I get them. Thanks again for your help,
Jim

TT2

My Feedback: (13)

Ditto on IFLYRC4FUN's thank-you's!

I've got a brand-spanking new ZDZ40 / Bisson Pitts muffler that's going on the front of a H9 Edge 540. I ordered a couple of Bambula 20x10 props and the drill jig from RCShowcase. After the order arrived (3 days later!!!) I measured the props only to find that they're actually closer to 19 1/2" than 20".

Just an observation...I'm certainly going to use the props. Cheap and pretty good quality.

-Tom

locomotive

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Hey all you ZDZ 40 guys......I have a question for you. I am building a Lanier Cap 80 incher that should come out to be about 15lbs.....would a ZDZ 40 pull it well or do I need more motor?
Thanks!

Scorpionjack

Use a 20 X 8 should turn over 7100.

Forgues Research

My Feedback: (7)

I think a 20 x 8 is a bit small for the ZDZ 40. I'm getting 7100 rpm on mine with a 20 x 10, and that is a bit small.

Scorpionjack

Roger your absolutely Right it is a 20 X 10 on mine. I guess the mind does lose things with age.

Forgues Research

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Tell me about it...LoL

locomotive

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Hmmmmmmmm.......must have my cloaking device on.......how well will a ZDZ 40 pull a 15lb Cap 232?
Thanks

Iflyrc4fun

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It will rip it through the air with unlimited vertical even pulling straight vertical out of a hang with authority . Have fun !!

Jim

locomotive

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Seriously?? More power then a locomotive?? Able to leap tall buidings in a single bound? How much actual thrust do you think they produce??
Thanks very much!!

Iflyrc4fun

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And able to leap tall trees with a single nudge of the throttle --- . Actually I built an aluminum plate engine test stand a couple years back and mounted it on a set of linear bearings I grabbed off a piece of machinery they were tossing at work. The stand was originally built for testing the torque and clutch set up on our 100 cc racing kart engines. It was fairly easy to attach a piece of aluminum angle on it that I mount the airplane engines on for break in and tuning. Although I don't guarante absolute accuracy I attach a hanging type scale to the test stand and use it for prop comparisons and thrust estimate. The scale showed about 24 3/4 lbs max. It might not be totally accurate but I believe it is within 1 pound. Contrary to popular belief it is not necessary to wear a cape when flying this engine but you might feel like you want to especially if you slept in a Holiday Inn!
Have a good one,
Jim

locomotive

My Feedback: (7)

Thanks Jim,
24 3/4 lbs of thrust would pull a 15 lb Cap 232 just fine wouldn't it?
Thanks again!
Shawn

rmh

A Lanier Cap at 15 lbs - They must have reworked that kit -if it is the ARF-
The first ones were quite tailheavy -even with a 4 lb engine.
The Midwest Cap at 15 lbs tho - works pretty well with the ZDZ40 -and with a tuned exhaust setup-does very well.
There a quite a few of these engines locally and so I have been able to get a good feeling for what real world performance is.
16 lbs is about the upper limit of good IMAC performance for all but vertical upline snap stuff.
13-14 lbs in a H9 Cap seen a few -had one of these - NO tuned muffler - really performs and will fly the Unlimited schedule very well.
for the flip and flop fans - about 13 lbs is a good number and the Diabotins at 15 lbs hover and recover well. Tho that's about all they do --
A22x8-or 22x10 Zinger Pro on a well maintained non piped engine seems to be the best overall setup here -at 4500 ft elevation.
For blast performance - a pipe is a real boost -well worth the extra effort .
Personally, I don't think you can find a better value in a forty engine.

locomotive

My Feedback: (7)

Thats great info...thanks.......The Cap is the kit not the Arf......I am pretty sure I can get it in at 15 lbs......maybe the ZDZ 40 and a tuned exhaust would be a good setup.
Thanks guys

peso

Good idea to have a tuned exhaust but remember the header has to be long enough otherwise you will loose all the good characteristics of this ZDZ 40 engine. With a header that is too short the engine is turned into a two-speed device. Not at all suitable for an aerobatic plane.
It is not easy to install a muffler with a long header inside the fuselage of that plane. I have tried.

rmh

The ZDZ40 does not exhibit any transition problems with a Magic muffler type tuned can - overall 22" for typical 6500-7500 rpm- I have done a number of em.
My new Rear Exhaust setup in a FAI patternship will use this setup also -
model is my own design.

So far -I see this as the only viable gas engine for a 11 lb FAI model.

peso

To be more specific it is the Krumscheid can that I have used. If it is installed inside the fuselage of a MW Cap the main spar of the wing will limit the header to 10”. With this length the engine does not run well. When I increased it to 12” there was a remarkable improvement. But now I had to hang it under the fuselage. Not so beautiful but very functional.

rmh

Tuned lengths are just that - as you found out -
The Krumscheid is a very good setup

Barry-RCU

I am wondering how you are all getting up to 7400 RPM on your ZDZ 40. I have one with a 20-10 Pro Zinger and at best only get 6200 RPM. I have about 3 tanks of fuel (14 oz) run in the engine so far. 40-1 Penzoil air cooled oil, S&W muffler, 93 Octane. Any comments?

rmh

My guess-only a guess -is that your "muffler" is causing the difference .
Try this - run engine OPEN STACK- that is , nothing on the exhaust port - The engine will not shut off on idle doing this - but what you are doing is finding a base line to work from.
adjust high needle for max - NO sag rpm- measure and record rpm.
The J&A Pitts type muffler gives 6300 rpm .
(typical)on broken in 40's here -on 22x10 Zinger Pro's
I run tuned cans on my own engines which improve power and run more quietly .

peso

Mine turns 6800 rpm open stack with MenzS 20x10. Unfortunately I don´t know how that prop compares with Pro Zinger.
A small warning. It is almost unbelivable how noisy it is open stack.

Barry-RCU

Dick thanks for the response. Mine certainly is not broken in yet. Tuned cans are quieter? Where would I get one of those. Are you talking about something like the canister mufflers RC Showcase sells? Thanks