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150 Johnson 1983compression #bs milling heads

M

moparman

New member
"Good Morning,
My '83 Joh

"Good Morning,
My '83 John. 150 with about 700 hours on it currently has 108-110lbs of compression in all cylinders except one, which has 103 lbs.
I want to mill the heads 15-20 thousanths to bring up the compression some. I am also adding new performance reeds, stuffers and am cleaning up the intake manifold with a porting tool. Also going to 1 & 5/16" carbs from 1" carbs.
Question: is my current compression too low to mill the heads-will the higher compression accelerate engine wear or create problems? Do these engine mods in general look like a good plan? Your thoughts/suggestions plz...
Thanks from a newbee to the site!!!
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"My question is if you are goi

"My question is if you are going through all this, At the same time changing the reeds, you have access to remove the piston, why not remove it and replace it with a new piston and ring, in this way you are guarantee to increase and fix a bad cylinder ?
You also mentioned the size of the carbs is this the measurement of the throat ?"
 
"The compression on that engin

"The compression on that engine was lowered to compensate for the poor quality gasoline we are forced to deal with. Milling the heads usually results in piston damage via pre-ignition etc.

To bring the compression back to normal (even), the best route is to tear the engine down and rebuild it as needed."
 
"Thanks guys for your feedback

"Thanks guys for your feedback.
I was hoping to spruce the ole girl up a bit without spending a lot of $ and going the rebuild route. Based on most of the advice & information I have gotten, this motor doesn't have much potential(low/small ports, restrictive exhaust, etc) compared to the newer loopers & other motors out there. So I guess I will run(baby) it the way it is until it dies and go for a bigger/newer model then.
Enjoy the weekend & THX....."
 
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