head cc's thought...

[kct11]

as i was checking the cc's of my heads last night, i got to thinking..... if i had the correct heat range plug that was longer then adjusted them to stick in about 3/16 farther (or less if needed) with some indexing washers.... why not? sounds like a way to take up the 2.5 or 3 cc's i would like to get rid of, and you can always go back with a simple plug change. i wonder if the few threads that would be in the combustion chamber would make hot spots, and the abillity of the heads to pull the heat out the the extra plug area in the chamber.

i am sure there are lots of thoughts on this one!

[Jay Smith]

Nothing new, some Pro Stock Racer in the past in santioned racing used that method to increase compression in a stock class where the stock CCed head was required..

Jay

[kct11]

after i posted this i ran out (in my pajama's its about 25 degrees in there) and quickly checked the voulume of 3/16 of plug........ i found out that 1 cc is alot more than i thought! lol it looks like it would take a lot of extra plug in there to take away 2 cc's i will play around later today with some clothes on and the heater going and find out.

[rock]

Add that to a head gasket change. If you are using the 1.2 you could gain comp. by switching to the .75. Head remains stock.
Rock

[YELLOWSS]

yeah, 1 cc has some mass. stock class every little edge can help.

[Freddie Webb]

Make sure the plug doesn't hit the top of the piston, if that's a crossflow.

[Dingie 2]

as i was checking the cc's of my heads last night, i got to thinking..... if i had the correct heat range plug that was longer then adjusted them to stick in about 3/16 farther (or less if needed) with some indexing washers.... why not? sounds like a way to take up the 2.5 or 3 cc's i would like to get rid of, and you can always go back with a simple plug change. i wonder if the few threads that would be in the combustion chamber would make hot spots, and the abillity of the heads to pull the heat out the the extra plug area in the chamber.

i am sure there are lots of thoughts on this one!---- You could see and feel gains by dropping the plug into the cylinder on short runs like in drag racing, In a non drag race boat doing this could cause cylinder temps to rasie,it could cause the end of the plug to get hot and cylinder temps to go way up ,should cause pre-ignition,slowing you down and a possible melt down.If the end of the plug has any small sharp edges in the cylinder it will glow after it has run and cause lots of problems. Joe R

[T-REX]

Juss cut tha heds for a comp gain...stick'in a torch closer to the piston iz juss ax'in for trouble...JMO

[kct11]

i am just going to leave it alone. it is actually togheter and running now. if i feel the need for more i will just pop the heads off and have them cut.