Ol' Ron
Well-known member
First I have to appoligize for the quality of the pictures.
Yesterday we got back to work on the 294 hafter too much turkey. We finished ibstalling the valves and did some measuring. After the valves were installed and adjusted we measured the clearance between the piston and head. At the same time I wanted to see how much clearance I had over the exhaust valve so I could run a power tip plug. The heads we are using are the new 74cc Edelbrock and they are a picture of beauty. After installing some aluminum balls over the valves and piston, and a .050" shim head gasket. We rotated the crank assy several times to check the clearances. I founf the edge of the piston to have .070", and the center come to have .090". This telles me two things, first the piston does not come all the way up to the top of the cylinder and the dome of the piston and head are a little differant. Not much to worry about, I will send the heads out to be milled .025"
Next came the removal of the first 2 threads of the spark plugs. The plugs we want to use are the NGK FR4 or 5, depending on heat range. another plug made by Autolite can also be used and in this case only one thread was exposed. I used a 45 deg counter sink to remove the threads and open up the area around the plug for better firing. Gota burn all that nasty stuff.
Yesterday we got back to work on the 294 hafter too much turkey. We finished ibstalling the valves and did some measuring. After the valves were installed and adjusted we measured the clearance between the piston and head. At the same time I wanted to see how much clearance I had over the exhaust valve so I could run a power tip plug. The heads we are using are the new 74cc Edelbrock and they are a picture of beauty. After installing some aluminum balls over the valves and piston, and a .050" shim head gasket. We rotated the crank assy several times to check the clearances. I founf the edge of the piston to have .070", and the center come to have .090". This telles me two things, first the piston does not come all the way up to the top of the cylinder and the dome of the piston and head are a little differant. Not much to worry about, I will send the heads out to be milled .025"
Next came the removal of the first 2 threads of the spark plugs. The plugs we want to use are the NGK FR4 or 5, depending on heat range. another plug made by Autolite can also be used and in this case only one thread was exposed. I used a 45 deg counter sink to remove the threads and open up the area around the plug for better firing. Gota burn all that nasty stuff.
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