piston weight
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Re: piston weight
You want a grams to hp conversion chart, or a grams to ET chart, let me know when you have such!
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Re: piston weight
Go over to, "Yellowbullet", and ask Mark O'Neal, the guy with the fat orange and white cat as his avatar.
Mark should/will know!
He owned Probe Pistons.
pdq67
Mark should/will know!
He owned Probe Pistons.
pdq67
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Re: piston weight
Inertial piston forces are a function of rpm, stroke length, rod ratio, and piston mass.redgoldstein wrote: ↑Wed Nov 29, 2017 7:17 am how much is 14 grams worth in a 7000 rpm motor new piston weight a little more thanks
The sensitivity of each variable (calculated independently based on a change increment of 10%) is approx as follows:
rpm = 20%
stroke = 13%
mass = 10%
rod = 3%
For a given engine all the above parameters must be considered.
Piston inertial forces may or may not translate directly into torque improvement since
the primary effect is on friction.
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Re: piston weight
I think there is a formula (or table) for calculating maximum piston speed. As I recall this calculation takes stroke, piston weight and RPM into consideration and may be helpful to the OP in getting an answer to his question.
Bill
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Re: piston weight
Piston speed is simple math of stroke x RPM.engineguyBill wrote: ↑Wed Nov 29, 2017 11:12 am I think there is a formula (or table) for calculating maximum piston speed. As I recall this calculation takes stroke, piston weight and RPM into consideration and may be helpful to the OP in getting an answer to his question.
There is no "maximum" piston speed. Back in the bad old days, 4,000 feet-per-minute was considered the "fly-to-flinders" limit, just as 10,000 RPMs was given as a physical barrier, or 150 MPH as a maximum possible 1/4-mile terminal speed. Today, engines turning 18,000 rpm with a mean piston speed of 4,800 FPM and a peak speed over 7,536 FPM, are routine, as are 300 MPH 1/4-mile speeds.
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Re: piston weight
Go to www.wallaceracing.com/Calculators There are formulas for just about any Car / Engine configuration.
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Re: piston weight
using rpm and stroke you calculate mean / average piston speed (Velocity)
using a more complex formula you can calculate max piston speed (Velocity)
remember that the piston slows down to zero velocity ATDC and ABDC
for the same stroke and RPM mean / average piston speed (Velocity) does not change with different rod stroke ratios, but max piston speed (Velocity) does.
Stan
using a more complex formula you can calculate max piston speed (Velocity)
remember that the piston slows down to zero velocity ATDC and ABDC
for the same stroke and RPM mean / average piston speed (Velocity) does not change with different rod stroke ratios, but max piston speed (Velocity) does.
Stan
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http://www.magneticlynx.com/carfor/carfor.htm
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Offering Performance Software Since 1987
http://www.magneticlynx.com/carfor/carfor.htm
David Vizard & Stan Weiss' IOP / Flow / Induction Optimization Software
http://www.magneticlynx.com/DV
Re: piston weight
I would say the answer is: "For all practical purposes, zero." I would be very surprised if someone could produce credible calculations in support of anything more than a few mousepower loss.redgoldstein wrote: ↑Wed Nov 29, 2017 7:17 am how much is 14 grams worth in a 7000 rpm motor new piston weight a little more thanks
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Re: piston weight
Piston speed is not a contributing variable.
The parameter that determines piston inertial force is piston acceleration derived from rpm, stroke and rod length.
Bill, I really like the term "mousepower". Very often performance parts really only produce mousepower.
The parameter that determines piston inertial force is piston acceleration derived from rpm, stroke and rod length.
Bill, I really like the term "mousepower". Very often performance parts really only produce mousepower.
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Re: piston weight
14 grams (0.030864717 lbs) - 12 diameter - acceleration rate of 900 RPM second.
note this for one piston as rotation mass not reciprocating.mass
Stan
note this for one piston as rotation mass not reciprocating.mass
Stan
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Stan Weiss/World Wide Enterprises
Offering Performance Software Since 1987
http://www.magneticlynx.com/carfor/carfor.htm
David Vizard & Stan Weiss' IOP / Flow / Induction Optimization Software
http://www.magneticlynx.com/DV
Offering Performance Software Since 1987
http://www.magneticlynx.com/carfor/carfor.htm
David Vizard & Stan Weiss' IOP / Flow / Induction Optimization Software
http://www.magneticlynx.com/DV
Re: piston weight
Like I said earlier, go over to, "Yellowbullet", and ask Mark O'Neal, the guy with the fat orange and white cat as his avatar.
Mark should/will know!
He owned Probe Pistons.
And if you do, please ask Mark to come over here so I can ask him something. Oh, just tell him that ol' pdq67 sent you asking, he knows me...
Thanks,
pdq67
Mark should/will know!
He owned Probe Pistons.
And if you do, please ask Mark to come over here so I can ask him something. Oh, just tell him that ol' pdq67 sent you asking, he knows me...
Thanks,
pdq67
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Re: piston weight
If your asking how much power difference, there's not a dyno on the planet that could measure that small of performance differential.redgoldstein wrote: ↑Wed Nov 29, 2017 7:17 am how much is 14 grams worth in a 7000 rpm motor new piston weight a little more thanks
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Re: piston weight
Unless it was lightened in such a way that the ring lands flex, reducing ring seal. Hello power lossCharliesauto wrote: ↑Wed Nov 29, 2017 7:06 pmIf your asking how much power difference, there's not a dyno on the planet that could measure that small of performance differential.redgoldstein wrote: ↑Wed Nov 29, 2017 7:17 am how much is 14 grams worth in a 7000 rpm motor new piston weight a little more thanks
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Re: piston weight
Agreehoffman900 wrote: ↑Wed Nov 29, 2017 7:07 pmUnless it was lightened in such a way that the ring lands flex, reducing ring seal. Hello power lossCharliesauto wrote: ↑Wed Nov 29, 2017 7:06 pmIf your asking how much power difference, there's not a dyno on the planet that could measure that small of performance differential.redgoldstein wrote: ↑Wed Nov 29, 2017 7:17 am how much is 14 grams worth in a 7000 rpm motor new piston weight a little more thanks