Educate me on a 12 bolt in a 78 K 10?

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73c20jim

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Just as an aside about torque. How does the change in ratio affect torque, if you can chassis dyno the same motor with different ratios and get the same horsepower.
 

73c20jim

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And horsepower is a calculated number from torque and RPM,
 

Bextreme04

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And horsepower is a calculated number from torque and RPM,
Horsepower is a measurement of torque applied over a period of time. When you change ratios, you are increasing torque and decreasing RPM to get the same amount of power. It's math.... and science!
 

Bextreme04

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Just as an aside about torque. How does the change in ratio affect torque, if you can chassis dyno the same motor with different ratios and get the same horsepower.
This page has the math for determining wheel torque and wheel force based on transmission gear ratio, engine torque, and final drive ratio. If you aren't interested in the math, you can scroll through to the pictures and the graphs at the bottom that do a good job of visually describing what happens to applied torque and force at the tire based on gear ratio and differential ratios.

https://x-engineer.org/automotive-e...hicle-dynamics/calculate-wheel-torque-engine/
 

Vbb199

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To start with, the early Ford gear sets are bevel cut gears. These offer more resistance than the spiral-bevel gear set in the GM rears.

The 1/4 mile racers could see this on their dyno tests. They combated this by fitting GM gears to the the Ford differential carriers. (very costly) Later, aftermarket gear companies provided spiral-bevel gears to fit.

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^ spiral bevel gears

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This shows the difference well. The automotive gear sets are really spiral bevel hypoid. This means the pinion gear is set at an angle to the ring gear (driven gear). That allows the pinion to be mounted lower than center on the axle.

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^ Hypoid

The second disadvantage to the Ford 9" is weight. On an integral axle housing, the carrier side bearings are supported by the housing. The removable Ford carrier requires the heavy casing for the side bearing support.

The last item is cost to put the 9" in a GM chassis. However you chose to do it, it is custom. Fabricators working on their own vehicle, this may not be an issue.

To answer your other question, the Dana 44 is much like a 12 bolt GM in strength. Dana 60's are an upgrade for both.


I appreciate this information right here.

I was deciding between a 9", 10 bolt, or 12 bolt for my c10.

Sounds like a 12 bolt would be the better option

@Bextreme04 check it out ^^
 

AuroraGirl

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I appreciate this information right here.

I was deciding between a 9", 10 bolt, or 12 bolt for my c10.

Sounds like a 12 bolt would be the better option

@Bextreme04 check it out ^^
Ford 8.8 inch, no takebacks, and no promises. if you give me a loaded 12 bolt. deal? deal :)
 

wanderinthru

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I appreciate this information right here.

I was deciding between a 9", 10 bolt, or 12 bolt for my c10.

Sounds like a 12 bolt would be the better option

@Bextreme04 check it out ^^
Been a minute, and I may be recalling wrong? Have it in my head @Turbo4whl was talking about a 12 bolt car. Personally I went with the 9 inch, mainly because I got one for a 100 bucks, and it and a 12 bolt car is the only ones I could find the lower (5.6 or lower, I got a 6.2) ratios for.
Good luck.
 

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