You don't happen to have lift springs do ya?

Josh

 

Ok here is a pic of me and the boy on it id say easy 380/400 lb. what do you guys think. Leave it be until she is all together?

 

Looks to me like you have big block springs, and a small block engine........

Seriously though, the springs may just be too long/stiff for the application. If they are new, they may need a bit of time to "settle", but that looks like a lot more than can be attributed to "settling" of the springs.

 

I would agree .. Are the springs original to the truck ? and what does the Vin say was the original motor for the truck?

 

Big block and small block springs do not make that much of a difference. Even moreso once the guys put their weight on it as in the demonstration.

Josh

 

The vin says 302 I installed a 347 stroker with aluminum heads. The springs are the springs came with the truck.

 

On my F350 dually it was 1" in height

 

So the springs are what they are .. You might go with some variable rate springs, if those springs are original .. It will ride a lot better .. and then cut to fit when your all done putting it together

 

I have another 1978 f100 I don't want to but maybe ill pull the springs of it and compare them. You guys think it makes a difference that the one im building is a 1978 1/2. is it possible the springs in there now are for a f150 that's heavier suspension right?

 

Comparing an F350 dually to an F100?

Josh

 

Ok there is 1 inch difference just measuring my parts truck is shorter it has in inline 6 in it. that could be it may have to switch them into it.

 

I'm comparing the difference in stock spring height in 2 motors only

 

That 1" difference will make a huge difference in camber. I bet it will sit much better on the shorter springs.

 

Yes, there is a difference. I put big block springs under a small block powered truck once. The result looked much like the pics posted by the OP.
Small block, around 450-500 lbs. Big block, 600+

 

So before doing all that work I loosend every bolt underneath drove the crap out of it on my gravel driveway and now it looks like the pic I have not tightend anything but I may be good now. Seems like it was stress on it after all.