Thread: Johns 66
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Old 04-29-2017, 09:56 PM   #33
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Re: Johns 66

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Originally Posted by Johns 66 View Post
At this point I am unsure what to do...I went ahead and took the heads off to see what the cylinders looked like. I then took some of the valves out of the heads to see what the valve seats looked like.

The cylinders measured 4.0 across, which unless I am wrong that is correct. The valve guides were leaking in some of the cylinders.

So what I thought at the start of the day ended with not knowing which way to go. On one hand the thought of a completely original drivetrain sounded really good, and I could go back completely as it came albeit rebuilt. This motor is a 220 hp motor, probably about 160 RWHP if I am lucky.......decision decisions......

Do I keep it stock or do I change some things? Hopefully someone will chime in with their thoughts on this.

I know there was a 365 hp 327 and based on my limited knowledge the only thing I could think that should be changed is the cam and the heads....I'm not sure if I can grind out the valve seats to put the bigger valves in it or not...I guess the machine shop will be able to tell me that...or should I just find a set of double hump heads and go that route...either way the heads have to be fixed no matter what I decide.

The cam and lifters will have to be changed as well.....lifters look like a saucer on the bottom,

It appears that I will have to rebuild the motor and at this point it probably is the better option because I certainly do not want to do this again in 4 or 5 months...even 2 years....

So my options are to build back stock or build it to the 365 hp specs.....at this point I am unsure what I am going to do.

Well if I was not concerned about being original I would build it to 300hp. Use a set of double hump heads and a mild cam.
The 365hp engine had high compression dome pistons and had a more radical cam. Just not a engine that I would recommend for a truck.
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