Cox ID

I thought that this was a Black Widow when I picked it up, am I right?
This one has a hexagonal section to the rear of the prop driver, a plastic backplate two internal transfers and two square exhaust ports.
I have a much older one which I had from new that has brass backplate and a pair of slit type ehaust ports each side, but the original pack was marked black widow.
Thanks

Yes that is a Black Widow. They varied from time to time. The key elements of the original concept are twin bypasses in the cylinder and the "stunt" venting of the tank. Sadly, the current Black Widows have RC venting on the tank and won't do for us CL guys without some fiddling.

Larry,

If this engine was swapped for the Hyper Viper engine, what might we expect to gain performance wise with this change?

If this change was a plus, what prop and fuel might you recommend for this combo.

Larry,
I have one also.
How can you tell if it has the twin bypasses in the cylinder?
Do the clipped cooling fins note this?
Chris

Lower the piston and look into the exhaust ports and you'll be able to see the bypass or transfer posts in the areas between the exhaust ports.

Look on the sides of the exhaust ports. There should be a little number, look real close.Sometimes it is on the base of the cylinder. The newer twin slit exhaust cylinders won't have any numbers. A #1 is a twin port cylinder a #2 is a single port cylinder, a #4 is a TD .049 and a #5 is a TD .051 to name a few.

Tim,
A #3??
Thanks,
Rob Johnson

Rob,

If I remember right a #3 is a twin bypass cylinder some with and some without SPI that were ground to use a throttle sleeve. I did not know till just now that Cox used a #4 as both a TD .049 and a Venom cylinder even though a real TD cylinder had 3 flutes per side and a Venom only 2!!

Hope this helps,
Tim

>Rob,
> TD .049 and a Venom cylinder even though a real TD
>cylinder had 3 flutes per side and a Venom only 2!!
>
>Hope this helps,
>Tim

Define 'flutes' ?

Thank you

Flutes are the "channels" cut into the cylinder that make the bypass.

The final run of TeeDee engines before I left had only 2 flutes per side, we found that worked really well. The un-symmetricality gave the fuel-air mix some spin. That gets amplified as the mix compresses, and causes better burning.

Larry,
Sorry to have to ask a naive question, but... How do you recognize r/c venting versus c/l venting on the Black Widow tank?
Thanks, in advance
Nick Vanmatre

Nick,
I don't mean to be answering for Larry but I believe he was referring to the newer BW's having the same type venting as the Texaco. You have a fill nipple and a vent hole on the backplate and no vents on the tank. I got a BW for my grandson Xmas before last and it had the "RC" venting.

What he said!

My black widow look exactly like the one in the picture for this thread. With fill/overflow vents in the TANK. So that is u/c venting? Correct? I hope, I hope...
Nick Vanmatre

LAST EDITED ON Mar-31-04 AT 07:37 PM (CDT)
 
Vents in tank....CL venting.

Mike,
The ones with the hexagonal thrust washer came with a plastic ring that fit over it to engage the starter spring. Many remove the ring because it slaps against the spring when running and robs some RPM.