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120” want to up the compression

Started by rking1550, February 18, 2023, 09:31:28 AM

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harpwrench

So what I was getting at is if the pistons were milled to 13.5cc then the domes reportedly might not be thick enough for plan B (milling them again to lower compression if you didn't like how plan A worked out)

jsachs1

Anything UNDER .200" crown thickness can put you in the danger zone, if your tune is off.
John

rking1550

Well, TR. called me back Monday night. He actually recommended NOT using the 662-3. He thought I'd be disappointed in the low end performance of the cam said it's all top-end. To get some low end torque I'd need the ccp to be around 230-235.  While I'm not afraid of compression I don't want to push it that high. 
His suggestion was to maybe add a little compression to the 662-2.  He said the heads could be cut some more , I'd need to check piston to valve clearance,  valve to valve would be a non issue. He also said if I decide to go/need to go 124" there's a lot more piston options and the 662-3 is better in a 124" or larger motors. Something to thing about for later ??? 
So the plan is to get it apart, see why the  rear cylinder has so much oil in it. And go from there. Rather than plan the new build first. Trying not to spend more than I have to right now.

 Thanks for the info and suggestions.
124"@ 11.1 to 1, T-man 662-2, T-man thumper, woods CV 51 carb,  Bassini RR