mdshaw
HalfDork
1/2/22 10:17 a.m.
After building my CR80 & tuning it & not exactly sure what the compression would be, I mixed up some 89 non ethanol & 100ll to get @ 94.5 octane. It runs like a scream'n Banshee. Checked the compression with a really good gauge kit & it's really high at 215psi. This is just too high & too much stress on the little rod & bearings from what I've read. I removed the head to check for any signs of pre-ignition & the head & piston look perfect.
I installed a different head which is new & never resurfaced with the old thin h.g. & compression was @212psi. So ordered a thicker 0.032" solid copper h.g. When it arrived it says I need to anneal it. My propane torch is a pencil tip. My question is can I use a propane stove to evenly heat it up to temperature? It's the perfect diameter & would get it evenly heated. But is it enough heat?
Thin hg
New copper hg
I've never done it, but just watched it done yesterday
8:00 minute mark
https://youtu.be/tM9AqyQrrPk
You can also stack a few base gaskets to bring the compression down
mdshaw
HalfDork
1/2/22 11:09 a.m.
In reply to Ranger50 :
From what I've read & instructions that came with it the oven at 500 degrees isn't nearly hot enough.
It says to take it through the color stages to red/orange almost molten.
But I don't want to melt it either.
mdshaw
HalfDork
1/2/22 11:11 a.m.
In reply to Mr. Peabody :
The base gaskets were probably the better plan. This cylinder has been machined a few times.
In reply to mdshaw :
That's how my buddy reuses copper gaskets on the old beezers and nortons he works on or a hot plate.
Cactus
HalfDork
1/2/22 12:27 p.m.
Copper melts at nearly 2000°F. I'm not saying you can't hit that, bit I don't think you have a whole lot to worry about. My main concern would be keeping it flat, so I'd stick it on a fire brick or flat tile. Get some rock wool insulation, make a little igloo for it on top of the brick and I think even a pencil tip moving about can heat it evenly. Remember, copper is one of the best conductors of heat, it'll get to temp pretty evenly just on that.
Honsch
Reader
1/2/22 1:32 p.m.
Hit it with a torch until it glows, cool any way you want.
Now you have annealed copper.
Jay_W
SuperDork
1/2/22 3:15 p.m.
Makes me wonder why the dern thing can't be annealed before you buy it ("pre-annealed for your convenience") but I dunno much about this subject..
In reply to Cactus :
I thought the point of annealing was to make the copper dead soft, so its flatness doesn't matter.
Me, I'd make sure the head and block were flat, spray both sides of the gasket with a thick layer of Copper-Kote, and run it.
Cactus
HalfDork
1/2/22 3:27 p.m.
In reply to Pete. (l33t FS) :
I assume you're right, but I'd still want it to be as flat as possible for my own peace of mind.
mdshaw
HalfDork
1/2/22 3:55 p.m.
I use the copper spray every time. Jug & head are super duper flat.
Tom1200
UltraDork
1/2/22 10:21 p.m.
In stick copper head gaskets for two stroke mx bike on the stove alk the time, works great.
In reply to Mr. Peabody :
True, but it changes two stokes port timing at the same time.
Minimally, but the effect will be more than offset by the still increased compression.
Ranger50 said:
In reply to mdshaw :
That's how my buddy reuses copper gaskets on the old beezers and nortons he works on or a hot plate.
"Beezer" is new to me. If you had not mentioned Nortons, I would not have been sure. Is that a new slang for Beemer, now that so many folks with a Bimmer are calling their cars Beemers?
Wow, say that 3 times fast
In reply to 03Panther :
Now it is slang for Birmingham Small Arm, er, BSA.
In reply to TurnerX19 :
Ah! That works. Makes more sense, now that I'm not thinkin' bout bmw