Magnum bore taper?

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nates68

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Been reading about how the magnum light tension moly rings and efi are friendly to the bores.
I have a motor that has 120k and had a blown head gasket on no.8. Pulled it apart to put new heads, cam,timing chain/tensioner on and clean it up for my install into a 68 barracuda. Was going to just run it because the oil looked good, no water in it.
However, even though the bores have the crosshatching, the tops of the cylinders (approx 1" down from deck and up) are worn, and after cleaning the carbon ring off the top of cylinder I can feel a slight ridge. It's not a sharp edge that a fingernail would catch on, more like a wave.
I put a piston ring in the most worn top area and then slid it down to the bottom of the cylinder and measured the end gap at both points. Only getting about 3-4 thousands difference (most are 3), and it is really only the very top of the cylinder that has wear.
So should I overbore .030, in which case I will likely do a stroker kit? Or just hone and re-ring
it? I was hoping to keep it a budget build but that never seems to happen :banghead:
Thanks,
Nates68
 
If it were me I'd be on my knees thanking the stars, (or who/ whatever) and then ordering a re-ring kit LOL
 
Great quick way to measure, I would still get an inside mike to measure out of round to help my decision.
 
Yeah I know it would be the right way to use a gauge, I rarely use them however. A basic set would be good. My biggest concern was the rings not sealing.
There are more than a few on here that are running stock bottom ends, including the magnum swap dart that runs high 11's in the quarter. Wonder if I am overthinking the wear.
Nates68
 
I would clean up the cylinders, new rings, bearings, and oil pump. Then run it till it breaks.
 
By cleaning up do you mean a flex hone or just the carbon on top? I know the magnum rings like a 30 degree crosshatch if I hone it.
Nates68
 
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