Stu26

Still waiting for my manifold to turn up so I can run it all up.

I did spot these today, anyone know if it will go straight onto my Z26SC and it it will will it be worth it?

[link]http://www.davesmotors.com/ca330_3[/link]

Look interesting

av8tor1977

My Feedback: (6)

Oh yeah. If yours is a four bolt cylinder flange, that should fit and it is a great mod. I built an engine with one of those cylinders and it is a killer. 10,200 rpms on an APC 16 x 8 WITHOUT a tuned pipe. The exhaust port timing is a bit high on that cylinder at 172 degrees, so it would do really, really well with a tuned pipe.

If you build it, don't lug it down with big props; let it rev. That's what it is designed to do.

AV8TOR

Stu26

What prop were you running?

I am going for a pipe so maybe the next upgrade.

Will this go straight onto the standard crank?

Stu26

what I meant to write, what prop would you recommend? I am trying a menz 18x8 to start with to see what that does.

I emailed Toni Clark ref the big bore kit and they said it was for cars and they had not tried it.

av8tor1977

My Feedback: (6)

I don't know if it would pull an 18 x 8 prop or not. When you hop them up they tend to lose low rpm torque. I generally use an APC 16 X 8 prop on this size engine, though I know a lot of guys run bigger props than I do. The Zenoah likes to rev though, and makes it's power at higher rpms. With that big bore kit, that is even more true due to the aggressive port timing. It may have been intended for cars or scooters, but it will work fine on an airplane as long as you don't overprop it. I haven't mounted mine and flown it yet, but I was extremely impressed with how it handled on the test stand. Starting, transition, midrange, and top end were excellent and very responsive. As far as flying it, I am not worried in the least as I have many times flown engines that I had modified to these same basic specs.

Yes, it is a bolt on, no modifications needed, deal. The kit even comes with the gasket and a spark plug.

Let me know if you use this kit and run it on a tuned pipe; I think it would be a fantastic combo that I just haven't gotten around to trying yet. Meanwhile, if you run it on a muffler, make sure it has plenty of open exit area so the engine can breathe at high rpms.

AV8TOR

dadragon

The Bowman rings would be a plus,more compression.I put his rings in a G-23 and the thing runs like a 26 about 100 more rpm.

kerwin50

Doesn't the UK have strict sound laws

Stu26

I now have all the bits. I got the Toni-Clark tuned pipe and it is a work of art!! the header I got is a perfect fit for drop but just touches the rear fins of the enigne. I will email them but I think I am going to have to file the fins a touch.

I hope to get it all assembled this week and then run up at the weekend.

Noise is a big issue in the UK. Some clubs are a strict 82db. I think I should get very close to that.

So hopefully I will end up with a powerful yet quiet combination.

Fingers crossed.

karolh

Keep us informed

Stu26

I had a bit of bad luck. I was removing the choke flap to solder the hole up and on undoing the screw it sheared flush with the brass bar. I have now got a replacement and the engine is almost assembled.

The brass fuel inlet is a smooth pipe. I am considering putting solder around the end to try and create a barb effect, I am just worried the heat will travel down the pipe and do some damage within the carb? What do you think?

Stu26

Well it runs!!!!

After finding out I have the hall effect sensor in the holder upside down and a bit of priming it is going well. Menz 18x8 and its topping out at 7800 with no tweaking of the needles and them both set at 1.5 turns.

I need to sort out the throttle linkage as with the geometry I had it idles at 4000!!! LOL I was keen to see if it ran!!

I am happy although not sure if the 18x8 is too much prop???? On Toni Clark he reckons on 8500 with the tuned pipe on the same prop so am a little off. Needles will give a bit but not sure if 700 rpm!!

Anyway very happy.

av8tor1977

My Feedback: (6)

I would just love to know how to cast small items like that manifold in aluminum. Anyone know of a good, simple, layman's "primer" on how to cast?? In fact, the manifold isn't all that pretty, so it is a somewhat crude casting. Not important; it works!! I'd love to be able to cast some small parts like that....

Thanks,
AV8TOR

Stu26

sorted out the throttle linkage, much better now.

Very slight tweak of the needles and it is holding a steady 8000 on the 18x8.

Anyone know how that compare to a JC28 or a DLE 30?

Pelle Gris

Something seems to be a bit off. A friend of mine ran a stock G-26 with a canister, and he got about 8.400 rpm on a Menz 18x8 as far as I remember.

Stu26

It has now flown as well!!!

Took it to the field and got it running ok. Mid-range was not so great but it idles and the top end was good. Flew it for 5 or so minutes. Dead Stick.......

Since then I cannot get it to start and the engines squeaks when I turn it over. It;ll fire on choke, then give one brrp off choke then do nothing.

I am at a loss as to what is wrong. I have took it out of the plane and its going to a friend of mine who fixes gas engines to look over and set-up.

I am still positive it will be good. I have to say the model weighed in at 5.2KG and was a bit worried that power would be lacking, but was pleasantly surprised.

When I get it back I will update.

av8tor1977

My Feedback: (6)

Doesn't sound good I'm afraid. Please let us know what happened. Did you purchase and use that hop up kit from DDM?

AV8TOR

Stu26

not had chance to take it over to my friend as yet. I do have a starter now. So thought I would try it again.

Fired up frist time and again ran ok idle and top end. Squeak has also gone. ( I think my in experience with petrols is showing now!!)

If I throttle up slowly, it is ok. Its only when I throttle up fast it hesitates and then catches up. Again had a fiddle with the needles and may have got it a little better.

With the start though it fires every time, so think I will keep that.

Stu26

I got frustrated with this, as the ignition and carb were the only non Zenoah Toni clark part I presumed that one of these was causing the issue.

So another Z26 came up at a good price and I purchased it. This time I added parts ran etc to see the difference.

Ran it up and it worked great. stock

Added the carb bend . all ok
Added the tuned pipe. hesitation back.

tried to tune it out but couldn't. SO it looks like the pipe is the issue.

Bit odd this as it is a Toni Clark part for the Z26.

I have emailed them so will see what comes back.

Stu26

Just went and tried the original engine with the rcexl etc but on a standard exhaust and the engine ran fine. 6800 on a 18x8 so 1000 extra on the tuned pipe??

av8tor1977

My Feedback: (6)

Yep, 800 to 1000 rpm gain on a tuned pipe is about what you get. It's a lot!

Try lengthening your pipe and see if it will tune. Going to an 18 x 6 prop might help too.

AV8TOR

w8ye

My Feedback: (16)

You have to turn enough rpm to get up on the pipe

karolh

Ditto that, think you are using too much prop.

Captain John

+1

dirtybird

My Feedback: (5)

Sounds like a job for a 3D printer
reply for post 37