bored over 40
08-17-2007, 06:40 PM
#21
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Join Date: Mar 2007
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RE: bored over 40
ORIGINAL: 4reboy
My windsor is bored .040 over. The machine shop that professionally builds race engines and all types of engines in general say that the overheating after .030 over is a myth. They bore to .060 over all the time without any problems and with full confidence. I trust people that were currently rebuilding a damaged hemi block (440 I believe)
My windsor is bored .040 over. The machine shop that professionally builds race engines and all types of engines in general say that the overheating after .030 over is a myth. They bore to .060 over all the time without any problems and with full confidence. I trust people that were currently rebuilding a damaged hemi block (440 I believe)
Jim
08-17-2007, 09:43 PM
#23
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Location: Citrus County, FL
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RE: bored over 40
while i agree that taking out more than you need to is stupid (your shortening the service life of the block), i wouldnt feel bad at all about .040 or even .060 on anything older. maybe some of the later model blocks cause everything seems to be thinner, but the older stuff i say game on.
and btw your not overheating cause the motor is .020 or .030 or w/e it is over, your overheating cause your cooling system isnt doing its job, or needs to be improved.
and btw your not overheating cause the motor is .020 or .030 or w/e it is over, your overheating cause your cooling system isnt doing its job, or needs to be improved.
08-17-2007, 10:02 PM
#24
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RE: bored over 40
ORIGINAL: 67mustang302
A good set of aftermarket heads solve a lot of the shrouding problems associated with stock heads. I prefer to keep the boring to an absolute minimum, just enough to clean the cylinder up if it's needed.
A good set of aftermarket heads solve a lot of the shrouding problems associated with stock heads. I prefer to keep the boring to an absolute minimum, just enough to clean the cylinder up if it's needed.
08-17-2007, 10:10 PM
#25
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RE: bored over 40
ORIGINAL: my77stang
while i agree that taking out more than you need to is stupid (your shortening the service life of the block), i wouldnt feel bad at all about .040 or even .060 on anything older. maybe some of the later model blocks cause everything seems to be thinner, but the older stuff i say game on.
and btw your not overheating cause the motor is .020 or .030 or w/e it is over, your overheating cause your cooling system isnt doing its job, or needs to be improved.
while i agree that taking out more than you need to is stupid (your shortening the service life of the block), i wouldnt feel bad at all about .040 or even .060 on anything older. maybe some of the later model blocks cause everything seems to be thinner, but the older stuff i say game on.
and btw your not overheating cause the motor is .020 or .030 or w/e it is over, your overheating cause your cooling system isnt doing its job, or needs to be improved.
I could see thinner cylinders contibuting to uneven expansion and cylinder distortion when hot,,, but I can not see issues with increased overheating....
08-17-2007, 10:22 PM
#26
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RE: bored over 40
Do you know how an aspirin cures a headache? All you need to know is the results. I don't know the how or the why a bored small block Ford generates more heat. I don't care. It happens, and I react accordingly - a larger radiator up to 0.030, andthe dump after that.
Jim
Jim
08-17-2007, 10:54 PM
#28
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RE: bored over 40
Overheating might be due to higher compression. Boring the cylinder will raise the compression ratio, all things being equal.
I've read that .040 is the maximum recommended overbore on a Ford small block but you can probably get away with .060.
I've read that .040 is the maximum recommended overbore on a Ford small block but you can probably get away with .060.
08-18-2007, 12:04 AM
#29
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RE: bored over 40
ORIGINAL: jcomp
Overheating might be due to higher compression. Boring the cylinder will raise the compression ratio, all things being equal.
I've read that .040 is the maximum recommended overbore on a Ford small block but you can probably get away with .060.
Overheating might be due to higher compression. Boring the cylinder will raise the compression ratio, all things being equal.
I've read that .040 is the maximum recommended overbore on a Ford small block but you can probably get away with .060.
08-18-2007, 03:45 AM
#30
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Join Date: Apr 2007
Location: California
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RE: bored over 40
I'm at .040 on mine and have no heating issues. But it's also running a heavier duty 3 core radiator. Even with the fan turning slow from the underdrive pullies at idle, sitting in traffic in Bakersfield when it's 110+ outside, it doesn't overheat. Or when I go down the track. I doubt the stock radiator would be able to cope, but then the engine isnowhere near stock either