Rear 4-Link Anti-squat HELP

[SC74]

I have finally gotten my project BIG COUNTRY to a "mobile" state. It has driven up and down the driveway on it's own power now. It even stopped itself too ;D

I have a rear 4-link with the coilovers mounted to the middle of the lower bars and coming up through the fender and tie to the roll cage. From just shifting gears, I have so much anti squat that the truck has +/- 12" of movement from shifting from forward to reverse. It's enough to throw you out of the seat literally. Where do I start? Is it in my spring rates or geometry?

 

[firehawk]

Sounds like geometry to me, did you use the 4 link calculator to figure it out before you built it?

Post the numbers of the 4 link and pics.

 

[SC74]

yes and no. The lower arms are IronBender's and the frame bracket are his too. His geometry has worked on other's rigs I know. My arms are not too steep which I know would cause the problem. I winged the spring rates before the bronco was together so I'm hoping I can fix it with some spring adjustments or gas charge in the coil over.

 

[TBS-POPS]

Use the 4 link calculater off pirate. its a good one. you need to plot in all your points for upper and lower links. its not spring rates its geometry.

 

[SC74]

I think I know what's thrown the geometry off. We moved the axle back 10" from stock. The brackets Jack sold me were made to go 10" further on the frame. In that 10" the frame rises and creates more angle in the lower arms. I am going to run it through Pirate's calculator and see how much I need to lower the brackets.