t_kwink

I had another test session with my reed valve project tonight....

Last session-
5.5-4 MAS prop, cox high comp. plug, 3 head gaskets, 25% Norvel fuel = 16,300

tonight- (shortened distance between carb and crankcase, and reduced crankcase volume)
5.5-4 MAS prop, cox high comp. plug, 3 head gaskets, 25% Norvel fuel = 17,600
5.5-4 MAS prop, Norvel plug, 3 gaskets, 25% fuel = 17,700
5.5-4 MAS prop, Norvel plug, 3 gaskets, 35% fuel = 18,000
5.5-4 MAS prop, Norvel plug, 1 gasket, 35% fuel = 18,300

I'll keep working on it,
Wink

Tim Wiltse-RCU

Wink,

That is GREAT!!!!! After meeting with you the other night I knew you would get that thing screaming one way or the other! After bouncing ideas off one another I have a few new tricks I am working on too! I guess what is even better with your news is that that is a good sized piece of lumber it's swinging too! How does it throttle? Get that thing to a point where you are happy and send it down and I'll anodize it for you. Of course you will have to make me something too

Later,
Tim

t_kwink

It is still acting as if the carb is too big for this engine without a preassurized fuel system, but every time I get it to pick up RPM, it seems to meter fuel better, sound cleaner, and throttle better. I am hoping there is still some left in it. I plan to move the carb closer still (touching the back of mounting plate). I also want to try the mylar reed as opossed to the stainless steel "oval" shaped one it has now, and I am considering trying a crankshaft and piston/rod with a shortened rod pin so I can move the backplate in further and increase the crankcase compression ratio a little more. I was really surprised at the performance of the Norvel glow plug. It actually GAINED RPM!!! If anyone else has some ideas (on the induction) let me know.

Wink

t_kwink

Tim, I would love to have you anodize this thing! Your work is very impressive. I work with a lot of parts at work that are anodized when we get them (probably in some mass quantity at some kind of factory), and I noticed that the pieces you brought were much brighter and more colorfull. The difference is kind of like the difference between a factory paint job on a new car, and some car show winner that has about 10 coats of clear coat. It is just.....brighter. When I can't get any more out of this thing, I'll make a couple of duplicates for 'ya.

Wink

Tim Wiltse-RCU

Wink,

I have a carb off a G-Mark .049/.061. It's is alot smaller than the AP carb. I'll send it to you to try out. I have a feeling it will be just the ticket!

LAter,
Tim

DICKEYBIRD

Very cool stuff Wink; way to go! I'd like to hear how your engine does with a Galbreath/Nelson head and also what rpm it will turn a Cox black 5x3. Keep up the great work!

mclintock

My Feedback: (3)

This is probably a silly thought, but I wonder if the prop blast is causing low air pressure in the reigon of the carb intake. Maybe try with it in pusher mode, or with a snorkel of tubing with the end out of the air stream?

That looks so cool.

t_kwink

Where in the heck do I get a nelson plug and head set-up? I haven't easily found one anywhere.

Wink

Andrew

Wink --

Try [link=http://www.the-printer.net/DookCat.html]here[/link] -- it's under Nelson head for Cox, AME

BTW -- great engine work -- this forum is a treasure trove of expertise!!!

the "other" andrew

t_kwink

I removed the supplied stainless-steel "oval" shaped reed and replaced it with a mylar "star?" shaped one. I ran the engine again, and it gained.......nothing. It ran exactly the same. Oh well.

Wink

ptulmer

My Feedback: (5)

WOW! That's so nice I'll say it backwards...WOW! [sm=spinnyeyes.gif] That thing is turning alot better than my cox's with a 5x3. Great work![sm=thumbup.gif][sm=thumbup.gif]

Tim Wiltse-RCU

Wink,

You can get the Galbreath Head and Nelson plugs at www.kittingittogether.com. It's RCU member Larry Driskills site.

Later,
Tim

t_kwink

Thanks for the info on the Nelson plug set-up guys.

Tim, I think I would be interested in trying that G-Mark carb if you would be willing... let me know.

Wink

Tim Wiltse-RCU

Wink,

Dude no problem at all. I had the whole engine but the rod was busted. I had it kicking around thinking someday I would find someone who needed something off it. I think Tom has the case and I just found the carb kicking around a couple of weeks ago in the box. It's yours to beat on as I have no plans for it. PM me your address.

Later,
Tim

t_kwink

That would be great, Tim. I tried to run this thing again tonight, but it is so tempermental that I got frustrated. It is clearly having carb isues. I am not sure if this AP carb is too big, or if it's something else. I am unhappy with the way the needle valve feels. It has a lot of slop in the threads. I can grab it and move it back and forth. When the engine is running, every time I touch the needle, the engine starts to stumble, and I am almost positive it is vibrating during the run. I would presume that it is also leaking air past the threads. Has anyone else experienced this with the AP Wasp .061 carb? Would teflon tape on the threads be the correct fix? I'm going to disassemble it completely first, and see if I see something funny.

Wink

t_kwink

Well, I put a good amount of teflon tape on the needle valve threads. I hope this helps. Can't wait to try.

Wink

t_kwink

I fixed it. I ran the engine again tonight after putting teflon tape on the needle's threads. It now runs and meters fuel perfectly. However, in all my excitement, I managed to straighten the coil of a Norvel glow plug with a lean/overcompressed run, and I then managed to break the snout of the crankshaft off while changing the plug. Maybe I shouldn't work on this little stuff after a stressfull day at work. I didn't get to test anything new, but it ran really smooth and clean at 18,300-18,400 with the 5.5-4 MAS, 35% fuel, and Norvel plug. After I fix it (again), I plan to try a TD piston and cylinder.

Wink

Tim Wiltse-RCU

Wink,

That flat out rocks dude!!! A pat on the back for a job well done!!!

Later,
Tim

t_kwink

Thanks, Tim. I recieved your carb today. It is in line after a few more tests, like a TD cylinder and piston. By the way, did you guys know that even the "modern" killer-bee engines have a different crank than other reedies? They look the same, but the extra material around the base of the rod journal is a little larger, and the O.D. of the crank is .500" where a standard reedie is about .528" all other dimensions appear to be the same.

Just curious, Tim, If you took a highly polished alluminum part and clear anodized it, would it keep it's original high luster?

I recieved a Tee Dee .049 the other day that I purchased from E-bay. It is (believe it or not) the first Tee Dee I've ever owned. If it wasn't for the lack of a throttle, that carb looks as if it would be pretty sweet. I like the multiple discharge holes they have in the venturi. It looks as if it would do a great job of atomizing fuel, but I bet that doesn't matter much after it all goes through the crankcase.

I'm rambeling---I think work is stressing me out.
Wink

BMatthews

Just a thought but how about opening the port timing up a little with a base gasket? Adding a shim there would advance the port opening times and delay their closing times. Longer port openings may help the top end a bit.

Andrew

Hmmmm -- an increase in deck height, with no other changes, will reduce compression and also shorten the duration of the power stroke. I'm not sure that will add to the top end -- but I haven't tried it, so .... anyone got some numbers? Larry Driskill or CombatPigg perhaps.

t_kwink

I bought a cylinder shim set on e-bay, but I haven't recieved it yet. raising the cylinder will decrease compression, but that is easily fixed by removing head gaskets. I have noticed that as I decrease the crankcase volume, (by cutting materiel from the rear) I need to add head gaskets. This makes sense to me because as you raise the crankcase compression, you are forcing more air into the cylinder, and thus raising cylinder preassure, so you need to add head gaskets to get the cylinder preassure back down where it was to achieve the same ignition characteristics. I am getting ready to go run the engine with the Tee Dee cylinder right now, and just for reference the piston is about .0025" ABOVE the deck right now. I read somewhere that a 0" deck is what you want, but it would be fun to do some testing and find out exactly where it is happiest.

Wink

t_kwink

O.K., I obviously had to replace the crank in this thing (after breaking the original killer-bee) and I used a standard reedie crank, cut the O.D. to .500" to duplicate the original, and cut .020" off the rod journal as I had done previously. I reassembled it with the Tee Dee .051 (sorry, I thought it was an .049, but it's not) cylinder and piston. I ran it as before with a 5.5-4 MAS prop, 35% Norvel fuel, and worked my way down to 1 gasket under a Norvel plug. It ran about 100 RPM less than the killer-bee piston and cylinder, and it had a TERRIBLE vibration. I assmued that I had missed something about the crank, but I switched it back to the killer-bee piston and cylinder and ran it again. It smoothed right out and ran as before at 18,300-18,400. From this, I will asume that either a .051 piston and rod are heavier than a standard .049, or the "new" killer bee piston and rod is still in some way lighter than a standard .049 reedie piston and rod.

I did get a chance to make a prop adapter for APC props, so just for kicks and giggles, I ran it with one"

APC 5.7-3, 35% Norvel fuel, 1 head gasket, 35% Norvel fuel = 19,800 RPM

I have no idea if this is good as I have never run this prop on anything before, so you guys will have to let me know. When running the APC, the engine reached a whole new level of smooth. When adjusting the needle, I couldn't hardly feel it running!!!

Wink

Tim Wiltse-RCU

Wink,

That is awsome...almost 20,000rpm. That is the limit you want to run on the ground before things start breaking!


I'm not worthy..I'm not worthy....

Your engine is truely a Cox that Rox!

Later,
Tim

t_kwink

How does it compare to a tee dee or a Norvel .049? Does anyone know what they will turn an APC 5.7-3?

If anyone knows, let me know,
Wink