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**68 C10 Driver** · 01-19-2021, 09:17 PM

I will be putting a crate SBC 350 4 bolt main into my truck...bolted to that will be a rebuilt Muncie M20 wide ratio 4 Speed. First gear is 2.56:1.

Because the truck originally came with an inline 6 cylinder engine, the rear end has 4.11 gears in it. I know the 4.11 has to go, so I am looking to replace the gears in the rear end and hope to get a happy medium between half-way decent take-off power and highway drivability.

So here is my question:

What gearing will give me the best drivability in town and on the Interstate? I am looking at 3.43, 3.23, and was also looking at 3.08.

I have been told that 3.08 may make the truck too sluggish taking off from a stop in town. Either way I do not want to be 'that guy' who holds-up traffic in town or on the interstate. I would like to be able to do 70 - 75 mph without the truck screaming at high RPMs.

Thoughts?

01-19-2021, 09:17 PM	#1
68 C10 Driver Senior Member Join Date: Oct 2020 Location: Kathleen, GA Posts: 623	Differential Gearing Question I will be putting a crate SBC 350 4 bolt main into my truck...bolted to that will be a rebuilt Muncie M20 wide ratio 4 Speed. First gear is 2.56:1. Because the truck originally came with an inline 6 cylinder engine, the rear end has 4.11 gears in it. I know the 4.11 has to go, so I am looking to replace the gears in the rear end and hope to get a happy medium between half-way decent take-off power and highway drivability. So here is my question: What gearing will give me the best drivability in town and on the Interstate? I am looking at 3.43, 3.23, and was also looking at 3.08. I have been told that 3.08 may make the truck too sluggish taking off from a stop in town. Either way I do not want to be 'that guy' who holds-up traffic in town or on the interstate. I would like to be able to do 70 - 75 mph without the truck screaming at high RPMs. Thoughts?