Front axle clearance

I am running a 39 axle 46 split wishbones with a mono leaf spring in front of the axle. Right now with no engine the frame is 3" give or take from the front axle. I will be running a *cough* Chevy 350. Anyone familiar with how much the weight of the motor will lower the frame. And what front axle clearance from the frame would be a minimum at ride height. The shop I bought the spring from wasn't much help. I still have about "1 of spacers left but this spring has put it real low. Any experience with mono leaf from Kenny's hot rods? When I jump on the frame with two people we can't get the frame to touch the axle

 

Right now you have about the minimum clearance with no motor installed, so when you put it in the front will probably drop another 2 inches or so. You need to get some additional clearance or you will be bottoming out. You have to add in not only the weight of the sbc but the trans, radiator, accessories, etc.

I like at least 3 inches clearance when all the weight it on the frame. One good bump or highway bridge seam at speed and you will be bottoming out.

Don

 

Thanks that is great. Seen your stuff. Appreciate the input.

 

Thanks. Post some pictures of what you have, that might help. You could also add some more spacers above the mono leaf, or you might find you have to go to a conventional 6 or 7 leaf spring to get the arch you need.

We had several Posies springs in the shop and once we had all the weight on the front of my Son's rpu it sat just a little low, so we swapped it out for their next heavier one and it was just right. They make them in various arches and reversed eye and non reversed eye models.

Don

 

I ll post a pic but I think I can lower the front cross member.

 

What I did when building my A was to set the vehicle on the ground just as it normally would be carrying the vehicle, with the suspension all in place. I then added a block, heads, etc to the approx weight of the engine plus rad, plus fluid, plus etc. just sitting on top of the frame on a couple of blocks. Then stand on top the frame and "bounce" it a couple times. This should give you a pretty good idea where the suspension will be when the engine etc. is installed.

 

I have 3" between the axle and the bumpers with a SBF and stock shocks set at "stiffest" setting. Any lower and the axle slams the bumpers on a bad bump. SBF is lighter than a SBC.