teddiepos10

My Feedback: (1)

Has anyone tried one of these special 24k .049 engines from ebay???
http://cgi.ebay.com/New-Cox-049-Cust...742.m153.l1262

kersplat

I have my doubts they will get 24K. Unless it is swinging a 4" stick on 60% nitro. I don't think the crank and cast case would survive.

forsakenrider

On one of his ebay descriptions it said it was doing that on a 4.2x2 or something rediculous. I remember the pitch was 2 forsure.... any cox will do that for a tank or 2 on a 4.5x2, c mon.

mikegordon10

It's like kersplat says, getting them to turn 24 grand is not the problem. We raced them in the past before the Norvels came on the scene. With just a few modifications we had the TDs turning 24,000 with 5 X 3 Tornado props. The problem was they would not hold together very long. The .061 Norvel AME's, on the other hand can be made to turn over 30 grand and hold together, this is with 4.6 X 2.75 props. All of this info is with 30% Sig fuel.

kersplat

That's what I think too. Now if it would get that RPM on a 5X4 on 10 % , now that would be something And dig that prop drive, It looks like it was turned using a drill and a file.[:@] It is interesting that it gets that RPM and it doesn't even have a Tee Dee head.

mikegordon10

Well after i looked at the link, I just have one thing to say "UNBELIEVABLE!".

planebuilder66

My Feedback: (8)

Wow, maybe I should take him up on the 45 buck and his 100% satisfaction policy, I bet it would be back in his hands burned out and no compression from me trying to bump the nitro and lean it as far as possible to get those #'s.

kersplat

He may deny the return because you have run it

flyinrog

My Feedback: (1)

Tim W had one run upwards of 30k, a special version he built...he said he was scared to stand too close to it as he wasnt sure how it was holding together screaming like that...dont know if it ran twice or not, he disappeared after that for a bit....Rog

gabe200

My Feedback: (21)

save youre money

teddiepos10

My Feedback: (1)

Hey guys thanks for all the input... I wasn't sure if this was legit... I thought that the engine may be stronger for normal running due to the mods...

teddiepos10

My Feedback: (1)

Is a plan old surstart worth buying???

planebuilder66

My Feedback: (8)

A plain old sure start is worth buying for a fun sport plane or something along the lines of a LST, gullows converted, but for high performance, get a norvel off of ebay, without throttle and it will knock the socks off any sure start or so called modified cox, even .049 teedee's have a rough time running in norvels range.

forsakenrider

heres a quote from [link=http://cgi.ebay.com/New-Cox-049-High-Performance-24K-RPM-Engine-Green_W0QQitemZ350153095107QQihZ022QQcategoryZ3405 6QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l126 2]this[/link]
"This test engine peeked 23,942 rpm's (Tach reads 47885 rpm's it reads both sides of the prop) with aAPC 4.5 X 2 and 19,500s with a Cox 5 X 3. "

Like I said. 2 for the pitch.... its like putting a prop from a pee wee on a regular SS engine. its screamin but not going anywhere.

I have a BabyBee with a black widow P/L that does 21000 on a 4.5X4.5 custom "windsor" I trimmed. Hello piston resets!

vertical grimmace

My Feedback: (1)

Like has been said earlier, 24,000 is no big deal for a TD. That is the redline though. They will not last long. That was what we ran for combat with a 5-3. Easy to get to with the Galbreth head.
I don't know about his engine, but the tach he is using is a POS! Not sure why he even bothered showing the tach in the video. not really doing him any favors trying to sell those.

kersplat

What I wanna know is what he held the piston with when he "trimmed" the lower skirt for SPI, a brass holding fixture ? Or did he just hold that finely ground piston directly in three jaws.

combatpigg

My Feedback: (3)

Has anyone tried to get any longevity out of the pot metal engines?

I'll bet one of these engines out pulls a CS or Brodak!

kersplat

I have a Testors "potmetal" .049 that still runs well. The crank fits the case like a hot dog in a barn but man does that engine scream at 11,000RPM[sm=bananahead.gif][sm=bananahead.gif]

lildiesel

I'd buy one if I needed another Cox. I'd also recommend getting a Sure Start with the machined block (bare aluminum) rather than the die cast block (grey with a different shape at the front). The machined block will mate properly with any old Cox parts (like fuel tanks) you might find at a yard sale or flea market. Some folks also have issues with premature wear with the die cast blocks.

combatpigg

My Feedback: (3)

Out of a batch of 5 Surestarts, I had 1 that could turn a 4.2x4 @24,000 after the piston was lightened. The combo works very well on a SWR. I didn't have to polish the outside of the cylinder, either .

gkamysz

My Feedback: (19)

If you follow the link in the auction to the youtube page it says he's turning a 4.5 x 2. At 24kRPM that's about 50W. It also says it turns a Cox 5x3 at 19kRPM, that's about 57W maybe a little more. About the same as stock Black Widow is it not?

It includes a 30 day warranty. Hook it up to a gallon of fuel and see how long it runs.

lildiesel

I didn't even bother to run the two SureStarts I got with the diecast blocks. The pot metal blocks not only looked like crap but I had doubts about the longevity. Even worse, the pot metal blocks didn't match up to the reed valve assembly on the Golden Bee tank I had in my parts box. One of them had the diecast engine's backplate (red reed retainer) and the other was assemble with machined block backplate (in black and looking like a better part and screws and no choke tube). The black one fit the Golden Bee block properly. Since I'd ordered them at the dirt cheap price from the Cox site so I just put them aside figuring I'd bought a couple of glowheads. Later on I got a couple of complete machined block, crank, and drive plate assemblies and proper backplate assemblies from a guy in B.C. and put together a couple SureStarts the way I wanted them for CL flying with my kid. The diecast blocks and the single proper backplate eventually went to another modeler who just wanted to have die cast block. Go figure.

combatpigg

My Feedback: (3)

kersplat, I made a bushing out of aluminum that is a nice fit to a .049 piston. It has about a 3/16" wall. A slit was cut into the side to allow it to clamp a piston for machining operations. This mod and crank journal relieving are 2 items that pay dividends.

MJD

My Feedback: (1)

LOL - that's a new one on me. I can think of an analogy or two that involves the fit of a hot dog.. but barns only figured in the picture when the subject turned to personal hygiene.

How come nobody is pinning their 1/2A hopes on OK?..

MJD

planebuilder66

My Feedback: (8)

at this point, maybe we should?..... o-awe, now I'm sad?![&o]