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Any Horse Power to be Gained?

General engine tech -- Drag Racing to Circle Track

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econo racer
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Any Horse Power to be Gained?

Post by econo racer » Tue Sep 10, 2019 9:53 am

Just for example I will use a 500 hp motor at 6000 rpm. Any Hp there to be gained using floater pins or pressed?

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Re: Any Horse Power to be Gained?

Post by mag2555 » Tue Sep 10, 2019 12:05 pm

A performance gain would come from a pin being lighter for sure , but as I don't think any friction reduction between a pressed pin or floater could be measured on a dyno.

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Re: Any Horse Power to be Gained?

Post by Warp Speed » Tue Sep 10, 2019 1:28 pm

Not sure how floating vs pressed fit effects the pin weight?!?
Any frictional gains would typically only be measured at high rpms.

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Re: Any Horse Power to be Gained?

Post by econo racer » Tue Sep 10, 2019 3:46 pm

So If the pins are say 20 grams each lighter could be something there. :D

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Re: Any Horse Power to be Gained?

Post by lefty o » Tue Sep 10, 2019 4:12 pm

econo racer wrote:
Tue Sep 10, 2019 3:46 pm
So If the pins are say 20 grams each lighter could be something there. :D
.0001HP.

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Re: Any Horse Power to be Gained?

Post by BigBlockMopar » Tue Sep 10, 2019 4:23 pm

Don't forget to add 2-3 grams for the pin-locks again.

A good cold air intake will net more power more easily.
Or a well tuned timing advance curve.

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Re: Any Horse Power to be Gained?

Post by paulzig » Tue Sep 10, 2019 4:33 pm

Stand on the scale and weigh yourself, 9 times out of 10 people can afford to shed some weight... Going on a diet and exercising might make a bit more difference than the weight of a piston pin, just saying...

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Re: Any Horse Power to be Gained?

Post by MELWAY » Tue Sep 10, 2019 5:20 pm

paulzig wrote:
Tue Sep 10, 2019 4:33 pm
Stand on the scale and weigh yourself, 9 times out of 10 people can afford to shed some weight... Going on a diet and exercising might make a bit more difference than the weight of a piston pin, just saying...
:D :D it might even make more power with a heavier pin if it made the piston more stable and retain its shape.
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Re: Any Horse Power to be Gained?

Post by FC-Pilot » Tue Sep 10, 2019 5:44 pm

MELWAY wrote:
Tue Sep 10, 2019 5:20 pm
:D :D it might even make more power with a heavier pin if it made the piston more stable and retain its shape.
Shhhh. Don’t give away all our secrets. Lol. Yep, depending on the piston design and use some times a heavier pin can help keep the piston supported.

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Re: Any Horse Power to be Gained?

Post by econo racer » Tue Sep 10, 2019 5:53 pm

Ok I get it there is nothing to be gained. How did you know I am fat :oops: Just 30 lbs.

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Re: Any Horse Power to be Gained?

Post by racear2865 » Tue Sep 10, 2019 7:25 pm

You could tell by the heavy writing.
reed

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Re: Any Horse Power to be Gained?

Post by Walter R. Malik » Tue Sep 10, 2019 7:28 pm

econo racer wrote:
Tue Sep 10, 2019 9:53 am
Just for example I will use a 500 hp motor at 6000 rpm. Any Hp there to be gained using floater pins or pressed?

The only gain with floating pins is that you can take them apart a lot easier and faster.
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Re: Any Horse Power to be Gained?

Post by gmrocket » Tue Sep 10, 2019 8:43 pm

Only disadvantage I see is when the piston rocks with a pressed pin it will not rock as easily due to the roughly double contact area.. could cause more scuff/heat on the skirt.

The higher the rpm the more pronounced that would be... heavier stock pistons make it worse.

Floating it tends to let the pin move in the rod, not the piston

Many times I've seen older builds with forged pRessed TRWs that have badly scuffed skirts .. mostly due too the way to tight pin clearance.

That definitely produces unwanted heat

Opening it up to .0007 to .001 is best

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Re: Any Horse Power to be Gained?

Post by Dave Koehler » Tue Sep 10, 2019 8:50 pm

I am waiting for the dyno sheets showing that a lighter pin will gain torque and the resulting HP.
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Re: Any Horse Power to be Gained?

Post by hoffman900 » Tue Sep 10, 2019 9:50 pm

paulzig wrote:
Tue Sep 10, 2019 4:33 pm
Stand on the scale and weigh yourself, 9 times out of 10 people can afford to shed some weight... Going on a diet and exercising might make a bit more difference than the weight of a piston pin, just saying...
This.

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