Differential Change

[fastglass]

I currently have a 1960 Corvette with a posi 4:10 rear end. I would like to change the ring and pinion out to a higher gear ratio (3:30 or so). Any advice or recommendations?

 

[Jack Martin]

I currently have a 1960 Corvette with a posi 4:10 rear end. I would like to change the ring and pinion out to a higher gear ratio (3:30 or so). Any advice or recommendations?

Easy change.

 

[JohnZ]

I currently have a 1960 Corvette with a posi 4:10 rear end. I would like to change the ring and pinion out to a higher gear ratio (3:30 or so). Any advice or recommendations?

You'll need a new Series 3 Posi unit (and ring and pinion gears) - you currently have a Series 4, and it won't accept gears numerically lower than 4.11. Eaton now has a new Posi unit made specifically for the C1 rear axle center section. That, plus a new speedo gear, and you'll be in business.

 

[Hib Halverson]

Well it's an easy change for the reasons above but it might not be if you have a close-ratio four-speed. Typically, close ratios with axle ratios higher than 3.55 tends to be a pain in the neck to drive and are hard on clutches.

Lastly, I sure you understand that going from the 4.11 gear down to a 3.36 is going to noticeably decrease the car's acceleration performance.