Strange cylinder

Nice work, that's a really cool mod.

Very cool indeed! Wondering if you used cylinder shims to index your single (open) exhaust-port straight back toward the pipe?

Admin wrote:

happydad wrote:

Admin wrote:

They pop up on eBay every few years and they don't sell for cheap.

Are those blank cylinders? Don't you have a smaller picture?  I mean a close up of the cylinders?

happydad           < (RC car emoticon)

Not my picture, it's the only picture I have from an old eBay auction years ago.

You are forgiven. oh, and +1.

happydad

Yes I bought cylinder shims from ebay to realign the exhaust port and blocked off the front port.
I then raised the timing by filing the top of the exhaust port from 140 deg stock to approx 162 deg.
I also ground down the bottom of the glow plug to recover compression from the cylinder shim.
Shims came in a pack of 4 two thin and two thick as I recall.


Profi Tuned Pipe TD RC .050 non SPI - 1st bench test
Tarno Carb, Cox buggy header pipe with half moon brass shim to block 1 exhaust port
#5 cylinder 2 bypass ports and 2 boost flutes per port -1 shim HC Cox Plug
Tad rich approx 85% to optimum break in mode with new #5 cylinder
- Idle with Tarno carb 12,116 rpm APC 4.5 x 4
- vid recorded 20,996 rpm on the pipe best noted 21,370 rpm 25% nitro

I have one of the blank cylinders and a piston and rod . The cylinder is threaded on top and bottom as normal but the inside remains to be machined ( bored but not finished or ground ) . The piston looks to be a thin wall when compared to other pistons but that it just an eye ball look on my part . I can't recall where I picked it up but some of my old friends are speed flyers and might have come from one of them .

Mike 1484

I will have some Cox cylinder blanks. Please see post for info if you are not already following that thread.
https://www.coxengineforum.com/t9328-cox-part-lot#118861