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The snowmobile heart heater; coffee cup, shiny coin in the cup, coffee until you can't see the coin, then moonshiners until the coin is visible...
 
Thanks. The xj is coming along.
Will move to rear fenders then to steering and suspension

I gt a hell of deal on this box. All left side drawers wouldn't unlock. 20200108_171607.jpg got it fixed it and filled it in a evening
 
Port mapping, machine work, and figuring out grinding outlines....

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Proper chineseium top end kit, but the numbers are shockingly close to what I want and I only had to take 0.005" off the base. Did the seals in it. Took of a mint thin ring top end that I'll save for another day.
 
.005 probably gets him to his desired Squish, no need for more.

Lol yes I understand that. Just wondering why go through the hassle of doing machine work and only tighten the squish up .005? That small of change isn't really going to do anything. Build a much better saw if he went with further via squish band cut or a pop up.
 
Lol yes I understand that. Just wondering why go through the hassle of doing machine work and only tighten the squish up .005? That small of change is really going to do anything. Build a much better saw if he went with further via squish band cut or a pop up.
He mapped it out, may not want to change the port numbers by cutting the squish band, pop up is a whole different ball game. You probably already know this, but I’ll throw it out anyway. I’ll defer to the OP.
 
288xp? Why only take .005 off the base?

Which lathe is that?
181se, but a huztl 288 top end. Without a base gasket it was at 0.025" squish so only had to take 0.005" off. Port timing was 109, 126, 76 after that. I'm shooting for 100-120-80 the rest is grinding now. And a muffler mod. Then it'll get put together with a v stack. Plan to use it as a small milling saw
 
The lathe is a 9" x 24" southbend from the 1940s. It's not perfect and has some slop but it's good enough for this kind of hacking
I use a Logan 210. 10x24. Not much younger than yours.

You won’t have much Comp if you raise the exhaust nine degrees and don’t do any machine work to the piston or combustion chamber. Take more off the base and at least do a pop up. Those number will work good. Same with 99 118 78. Pretty much anything around those numbers work good for a 288.
 
won’t have much Comp if you raise the exhaust nine degrees and don’t do any machine work to the piston or combustion chamber. Take more off the base and at least do a pop up. Those number will work good. Same with 99 118 78. Pretty much anything around those numbers work good for a 288

Didn't read this until this morning so it's too late now, all the grinding is done and the port timing is set. When you say "won't have much comp", how little compression do you mean? I imagine around 160psi should be fine? it seems to pull over with decent compression (by feel) now.

I may order another piston and weld a pop up on if the saw is underwhelming. Or just get another whole top end kit, they are cheap. I don't have a 4 jaw chuck for the lathe so cutting the squish band is out of the question for now.

I read through a bunch of 288 build threads on here before I started to get ideas. Thanks for providing guidance
 
Didn't read this until this morning so it's too late now, all the grinding is done and the port timing is set. When you say "won't have much comp", how little compression do you mean? I imagine around 160psi should be fine? it seems to pull over with decent compression (by feel) now.

I may order another piston and weld a pop up on if the saw is underwhelming. Or just get another whole top end kit, they are cheap. I don't have a 4 jaw chuck for the lathe so cutting the squish band is out of the question for now.

I read through a bunch of 288 build threads on here before I started to get ideas. Thanks for providing guidance

The higher the exhaust the less time there is to trap mix in the combustion chamber. If the combustion chamber wasn’t downsized and you raised the exhaust nine degrees I find it hard to believe the compression will be very good. Compression makes power. Those saws stock are known to have 180 psi or more. Since you have a lathe you should have at least done a Pop up. 288 piston have plenty of meat on them for a good sized pop up.
 
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