254/346 Hybrid Build “documentation” thread thingy… idk

[srcarr52]

This is cool!
103 is a pretty high exhaust for a ported 346, but who knows in a hybrid?

103 would be fine on a 346. With 2mm longer stroke it should be good.

 

[ZukiRyder440]

Ahh shoot i forgot.. im gonna get it runnin right tonight

 

[ZukiRyder440]

103 would be fine on a 346. With 2mm longer stroke it should be good.

I dug through my notes and my stock 254 jug timed at 103 121 72, and it ran rather well. I might shoot for the same ex timing and transfer timing, but drop the intake down to 78-79 range. But with the new piston ill do a comparison as far as “stock” timing goes. The skirts on the brush cutter piston look at tad bit shorter but pictures dont usually tell the whole story… well see when we get er

 

[ZukiRyder440]

Found the culprit…

 

[ZukiRyder440]

Replaced the old decomp with a plug.. and did a couple other small things.

 

[ZukiRyder440]

I dround down the heads of the cylinder screws to give me a little more room too, as well as going with. an .080” spacer, 1 .040” gasket and a .060” gasket to fet my .0245” squosh. Everything still fits under the rop cover so thats a plus

 

[ZukiRyder440]

Ill get some more videos of it running tomorrow, should be fine now that the kill wire isnt grounding out on the flywheel looll

 

[ZukiRyder440]

Gonna be trying this carb out for science n stuff.. its an HDA 159 i had layin around. Ehh why not. Ill do a comparison video between the two. If there is any difference at all.

 

[ZukiRyder440]

Doing this in real time so bear with me.. i havent done a real time tear down/ build yet. Ill try and go through everything i do and explain the point behind it.

 

[ZukiRyder440]

Scratch the 159… ilthe throttle shaft is tweaked and will not return to idle with out a push back. Next option is a zama el42, can really swap shafts but ill get it to work without the stock shafts

 

[ZukiRyder440]

Alrighty. Im going out to do some test cuts.. first video is going to be with the stock 254 carb.

 

[ZukiRyder440]

Funny how a funky kill wire can make it seem like a fuel delivery issue? It runs waayy better. And it still has the 120 carb on it. Im letting it cool down as of right now and ill post pics again

 

[ZukiRyder440]

Another one same wood as the first round., i think it will wake up nicely to some more compression and port work

 

[ZukiRyder440]

Some disassembly pics

 

[ZukiRyder440]

Heres the zama copy i run on my 346. Doesnt look like itll take too much work to fit on the 254

 

[ZukiRyder440]

I got it on. No tweaks were made to anything.

 

[ZukiRyder440]

All i had to do was flip the choke lever upside down. Its gonna be a little weird having the choke out when running but itll do for now

 

[ZukiRyder440]

Found a spare choke lever to work with this. I clipped the bottom guide tab for the old 357/57 cluster.

 

[ZukiRyder440]

Re assembly pic

 

[ZukiRyder440]

Ready for a test run