Hey Lads,
I was wondering, is there a specific formula I could use to determine what kind of rates I would need for the springs as well as the compression & rebound rates for the shocks?

While the A15 isn't that much heavier, I'm somewhat worried about the idea of a B140's entire drivetrain being heavier.

Also, she rolls a bit too much in turns around our mountain pass. I realize it might be that the suspension is 40 years old...Still, I can't have my brother or father getting in with me without the the GX begging for mercy.

Last time I went bonkers and way too stiff, so I won't be lazy this time. Show me the math

You will need to measure the weight across the front axle. Or even more accurate would be the corner weights.

Mmmm....found a few calculators that work off the cornering weights, but how do I establish what the weights are without a full-fledged telemetry system?

Put a scale on each wheel.

Or just look up the specs for the GX

Lmao, thanks a stack. I honestly didn't think it was that simple. Thought they based the suspension on maximum cornering force and adjusted to comfort.

To to measure corner weights is simple.

To use math to determine the maximum cornering force is not simple.

Math for comfort is complicated. You would need to know the corners weights, the unsprung weight, wheelbase, track, center of gravity and much more. The good news is that Nissan has already done the work, the front of the 1200 is set up for maximum comfort with a spring rate of 89.6 pounds per inch. And indeed it rides smooth. The rear unfortunately is not, but is configured for payload capacity (four adults plus luggage).

How about a hardass fellow like myself who has a love for terrorizing every corner? So when I have these retentioned (or new ones bought, I'm looking for something around rear spring stiffness to sate my motorsport needs? Its a daily driver, but I'm trully a hardass guy and our roads are pretty decent here....mostly... If stock works best with the new drivtrain, I appreciate you boys making it simple for me.

Thanks Guys