60" or 64" rear springs

[70custom20]

I'd like to change the rear springs in my truck at some point. I saw in the "towmissle rebuild" thread that the guy put 60" springs from a '92-'99 suburban in the truck. The truck is a square body. I read that guys put 64" rear springs under their trucks. Does anyone think that the ride would be significantly different between the two springs? Just quickly looking under my truck, it looks like the 60" springs might be a little bit easier to swap into the truck for the fact that the spring hangers won't have to move as far fore and aft. Thanks for input.

[70custom20]

I guess I should add that the truck is a '70 LWB pickup. My goal is to use the truck more as a tow rig for pulling an enclosed trailer.

[OLDCHEV4X4]

Hey Kurt! The longer the spring, the better the ride. And the more travel you get too. Its a little more work to do the 64's (cutting rivets sucks) but i think its worth it.

link--->http://67-72chevytrucks.com/vboard/s...d.php?t=480181

And you could do a shackle flip while your at it.

[Ziegelsteinfaust]

I found grinding rivets off easier, and then driving them out with a punch.

Also I was researching the longer springs too, and often they lift a truck 4 inches in the front when they use the 52 inch springs.

The rear doesn't seem to do it that much if at all.

[obijuan]

if you have any measurable amount of power they will wrap up on command. not a good choice for a high powered or offroaded rig.

[70custom20]

Originally Posted by obijuan

if you have any measurable amount of power they will wrap up on command. not a good choice for a high powered or offroaded rig.

Not sure what you mean by your reply. The 64" springs are still used today. I use the truck mostly as a street driver/occasional tow rig for an enclosed trailer. The truck has a basically stock 454, but I have plans to try to have a 500+" BBC built for more grunt. Ultimately I want a better ride for the truck. I'd like to do a long front spring conversion as well. I was looking at possibly using a 48" long spring from a '88-'93 Dodge, or just go with a 52" spring like other guys have.
Maybe I'm over thinking this swap, but the thing I'm not sure of where the placement of the front spring hanger. With the factory length 52" springs the front spring hanger is mounted on an angle on the portion of the frame that kicks upward to go over top of the rear diff. With the spring swap the front spring hanger would move forward onto the section of the frame that runs parallel to the ground. Not sure on how to know where to locate the front hanger.

[obijuan]

this is what happens with chevy 63s and torque

https://www.youtube.com/watch?v=lQoRounykJQ

[Redcap]

A good air chisel makes short work of those rivets.

[70custom20]

That's cool, thanks for posting the video. I guess I'll cross that bridge if I ever get there. BBC torque won't match the torque of a diesel that's had the wick turned up. I like the truck, I'm just a little older than I was when I got the truck on the road, so for me I'm looking for a better ride. Pulling an enclosed trailer with old iron isn't something you see every day.

[OLDCHEV4X4]

Originally Posted by obijuan

this is what happens with chevy 63s and torque

https://www.youtube.com/watch?v=lQoRounykJQ

If he took that large lift block out of there, alot of that spring distortion would go away.

Kurt, i took lots of measurements, made drawings, put a plumb bob on my frame, found the center of the axle, painted reference marks on the frame and axle, then disassembled the whole deal. When i bolted my springs on my axle and got my plumb bob marks lined up, I could see where the hangers had to be. I c-clamped the hangers to the frame and put the weight of the truck on it, then adjusted to get my height correct.
Hope that helps a little. You will figure it out as you go along.