pull/pushrod suspension

[David Pozzi]

It looks like you will lose a huge amount of spring rate due to the low pushrod angle. Gaining it back, or choosing a good shock rate and spring rate will be a challenge. I'd give a hard look at what is the stock spring rate at the wheels, and try to achieve that or slightly lower since you say it won't be loaded that heavily. I've seen street rod pickups that had 150 lb/in coil springs used on them and were still pretty stiff.



It's hard to tell where you have it now, but at normal ride height, set the rod to bellcrank arm angles at 90 degrees.

[Ripper]

Mount the coil over in a horisontal position instead of a vertical and adjust the rocker arm (or whatever it's called in english...).

Here's an example of positioning the coil overs;


Don't do the modification to gain unsprung weight... If you want to chase weight, start with swithcing the rear axle for something lighter...

[greencactus3]

It looks like you will lose a huge amount of spring rate due to the low pushrod angle. Gaining it back, or choosing a good shock rate and spring rate will be a challenge. I'd give a hard look at what is the stock spring rate at the wheels, and try to achieve that or slightly lower since you say it won't be loaded that heavily. I've seen street rod pickups that had 150 lb/in coil springs used on them and were still pretty stiff.

It's hard to tell where you have it now, but at normal ride height, set the rod to bellcrank arm angles at 90 degrees.

as of that sketch i had the rod to bellcrank angle at 90 degrees at full droop. any reason to have it 90 at ride height other than the 'efficiency' of it being at 90?
how much total bellcrank angle movement do you suggest i aim for?
as of now it is 102.5 degrees of total movement of the bellcrank across 6in of travel at the wheel.
for 3" of bump and 1" of droop, 67.3 degrees.

Mount the coil over in a horisontal position instead of a vertical and adjust the rocker arm (or whatever it's called in english...).

Don't do the modification to gain unsprung weight... If you want to chase weight, start with swithcing the rear axle for something lighter...

i dont see the reason why i should position them horizontal. the main reason for this is due to packaging issues trying to fit it under the bed floor. also, im not famliar with ferraris, but from that picture it seems to just be a cantilevered uca? rather than pushrods?

6" travel is way too much. You'll get trouble with the rocker arm geometry, unless you're planning some serious off road driving...
1" droop and 3" bump of wheel movement (which means even less damper movement. Depends on what ratio you're going for on the rocker) would be more than enough...

that is the numbers ive heard too, but i figured daily driving in michigan roads calls for the need for more than the 'standard'.
even if the shock never sees full extension or full compression, i would much rather know that the shock is not destroying itself.
as far as i can tell with that current sketch, the rocker arm geometry seems to work fine throughout the full travel.

[jerome]

how much lower than stock are you planning? How big is your frame notch? It looks like just a small 2 inch notch. Theres definitely room to mount coilovers conventionally. Design the axle mount to put them 5 or 6 inches below axle centerline, crossmember at top of frame just below bed, and if necessary you can angle the coilovers in.

Jerome

[greencactus3]

how much lower than stock are you planning? How big is your frame notch? It looks like just a small 2 inch notch. Theres definitely room to mount coilovers conventionally. Design the axle mount to put them 5 or 6 inches below axle centerline, crossmember at top of frame just below bed, and if necessary you can angle the coilovers in.

Jerome

im aiming for a 6" ground clearance to the frame, so that would be about a 4 to 5" drop from stock i believe.

it is a 2.25" notch

i am also running som pretty short tires (24.7") and seeing the massive craters of potholes we have around here, i dont want to have anything hang down that low.

but if all else fails with the bellcrank idea, that method will work.