Pistons
10-13-2022 | 06:32 AM
#11
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1. The J/E piston is for a 4.525 bore OR is it for a 4.530 bore and measures 4.525?
2. are either set of pistons 2618 or are they 4032?
3. when you buy say a set of J/E "4.530 pistons", unless you call JE up and custom order a set of ACTUAL 4.530 OD pistons (which would require a 4.535 bore =/_), you are actually getting a piston that fits that 4.530 bore size once accounting for "normal" clearance. Now, lets say the piston is a SRP 4032, it would measure about 4.526, a 4.530 bore would give you .004 piston too wall. Lets say it was a 2618, it would be more like 4.525 OD and give you .005 piston to wall in a actual 4.530 bore. Now, lets say you wanted a target clearance of .007 for some reason, you might hone block to 4.532 , or if piston started life a 4.525 and is worn to 4.524 youll end up at .006 or higher. You may very well NOT have a problem, Smitty
2. are either set of pistons 2618 or are they 4032?
3. when you buy say a set of J/E "4.530 pistons", unless you call JE up and custom order a set of ACTUAL 4.530 OD pistons (which would require a 4.535 bore =/_), you are actually getting a piston that fits that 4.530 bore size once accounting for "normal" clearance. Now, lets say the piston is a SRP 4032, it would measure about 4.526, a 4.530 bore would give you .004 piston too wall. Lets say it was a 2618, it would be more like 4.525 OD and give you .005 piston to wall in a actual 4.530 bore. Now, lets say you wanted a target clearance of .007 for some reason, you might hone block to 4.532 , or if piston started life a 4.525 and is worn to 4.524 youll end up at .006 or higher. You may very well NOT have a problem, Smitty
10-13-2022 | 09:52 AM
#13
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From: Dawsonville, GA
I was running a 427 in a drag car years ago and I think it was somewhere around .013" skirt to wall clearance... not because that was ideal, but because I didn't want to put new slugs in a worn-out block.
It was a little noisy on cold startup but ran like a scalded cat with a 325hp shot of nitrous.
Of course a short stroke with long skirts is alot different than a longer stroke with short skirts...
If it were me I would order a fresh set of custom pistons to match the existing bore. JE will make them however you want. I ran a 513 one time that was a .137" over GM block and a 4.250 crank. JE made me 10 pistons for it.
It was a little noisy on cold startup but ran like a scalded cat with a 325hp shot of nitrous.
Of course a short stroke with long skirts is alot different than a longer stroke with short skirts...
If it were me I would order a fresh set of custom pistons to match the existing bore. JE will make them however you want. I ran a 513 one time that was a .137" over GM block and a 4.250 crank. JE made me 10 pistons for it.
10-13-2022 | 10:50 AM
#15
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10-13-2022 | 11:43 AM
#17
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motor stuck a valve on cylinder 4 and injested water in cylinder 4, it says and must have pitted but didn’t affect the bore, just needs a hone. Rest of the motors is fine, heads have been rebuilt since.
10-13-2022 | 11:44 AM
#18
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1. The J/E piston is for a 4.525 bore OR is it for a 4.530 bore and measures 4.525?
2. are either set of pistons 2618 or are they 4032?
3. when you buy say a set of J/E "4.530 pistons", unless you call JE up and custom order a set of ACTUAL 4.530 OD pistons (which would require a 4.535 bore =/_), you are actually getting a piston that fits that 4.530 bore size once accounting for "normal" clearance. Now, lets say the piston is a SRP 4032, it would measure about 4.526, a 4.530 bore would give you .004 piston too wall. Lets say it was a 2618, it would be more like 4.525 OD and give you .005 piston to wall in a actual 4.530 bore. Now, lets say you wanted a target clearance of .007 for some reason, you might hone block to 4.532 , or if piston started life a 4.525 and is worn to 4.524 youll end up at .006 or higher. You may very well NOT have a problem, Smitty
2. are either set of pistons 2618 or are they 4032?
3. when you buy say a set of J/E "4.530 pistons", unless you call JE up and custom order a set of ACTUAL 4.530 OD pistons (which would require a 4.535 bore =/_), you are actually getting a piston that fits that 4.530 bore size once accounting for "normal" clearance. Now, lets say the piston is a SRP 4032, it would measure about 4.526, a 4.530 bore would give you .004 piston too wall. Lets say it was a 2618, it would be more like 4.525 OD and give you .005 piston to wall in a actual 4.530 bore. Now, lets say you wanted a target clearance of .007 for some reason, you might hone block to 4.532 , or if piston started life a 4.525 and is worn to 4.524 youll end up at .006 or higher. You may very well NOT have a problem, Smitty
10-14-2022 | 12:58 AM
#20
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1. The J/E piston is for a 4.525 bore OR is it for a 4.530 bore and measures 4.525?
2. are either set of pistons 2618 or are they 4032?
3. when you buy say a set of J/E "4.530 pistons", unless you call JE up and custom order a set of ACTUAL 4.530 OD pistons (which would require a 4.535 bore =/_), you are actually getting a piston that fits that 4.530 bore size once accounting for "normal" clearance. Now, lets say the piston is a SRP 4032, it would measure about 4.526, a 4.530 bore would give you .004 piston too wall. Lets say it was a 2618, it would be more like 4.525 OD and give you .005 piston to wall in a actual 4.530 bore. Now, lets say you wanted a target clearance of .007 for some reason, you might hone block to 4.532 , or if piston started life a 4.525 and is worn to 4.524 youll end up at .006 or higher. You may very well NOT have a problem, Smitty
2. are either set of pistons 2618 or are they 4032?
3. when you buy say a set of J/E "4.530 pistons", unless you call JE up and custom order a set of ACTUAL 4.530 OD pistons (which would require a 4.535 bore =/_), you are actually getting a piston that fits that 4.530 bore size once accounting for "normal" clearance. Now, lets say the piston is a SRP 4032, it would measure about 4.526, a 4.530 bore would give you .004 piston too wall. Lets say it was a 2618, it would be more like 4.525 OD and give you .005 piston to wall in a actual 4.530 bore. Now, lets say you wanted a target clearance of .007 for some reason, you might hone block to 4.532 , or if piston started life a 4.525 and is worn to 4.524 youll end up at .006 or higher. You may very well NOT have a problem, Smitty
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CR9190?
