Designing a Rear Leaf Spring Suspension to hook & not squat

Shocks, Springs, Brakes, Frame, Body Work, etc

Moderator: Team

BBCFAN
New Member
New Member
Posts: 28
Joined: Sun Sep 13, 2015 10:13 am

Designing a Rear Leaf Spring Suspension to hook & not squat

Post by BBCFAN » Fri Sep 09, 2016 10:29 pm

I am looking to put new leaf springs & hangers from a Newer GM 1 ton truck on an older frame.

The springs & hangers I have are for a 3 inch wide spring from a 2015 1 ton Chevy truck.

I am trying to make it so the truck is a stiff as possible with zero spring wrap.

My theory is with the longer, wider springs it will spring wrap less & be easier to launch.

Truck will be about 1100 hp running 35 inch dot tires.

Any advice or tips to avoid spring wrap when mounting spring hangers to frame?

User avatar
Alan Roehrich
Guru
Guru
Posts: 2976
Joined: Tue Jul 04, 2006 5:58 pm
Location: Murfreesboro TN
Contact:

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by Alan Roehrich » Sat Sep 10, 2016 9:33 am

We used a "leaf link", which was basically a 4 link that used the leaf spring as the lower link, and a large tube adjustable upper bar and brackets, equal in length to the spring, from the center of the axle to the front spring eye. We also used the biggest shocks, with the stiffest compression valving we could find.

j-c-c
Member
Member
Posts: 171
Joined: Sat Sep 03, 2016 9:03 pm

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by j-c-c » Sat Sep 10, 2016 1:23 pm

"I am trying to make it so the truck is a stiff as possible with zero spring wrap.

My theory is with the longer, wider springs it will spring wrap less & be easier to launch."

I don't think spring width is a primary concern for your goals, if handling was, then maybe.

"Stiff as possible" serves little purpose unless you are hauling rocks/dirt.

An asymmetrical leaf (ala mopar style) is a starting point for wrap up concerns, but not a solution I suspect in the 1100hp arena.

Longer front leafs are the wrong direction countering spring wrap.

A PU will as likely benefit from as much weight transfer as you can get, and I'm sure others will chime in on geometry/linkage solutions

BBCFAN
New Member
New Member
Posts: 28
Joined: Sun Sep 13, 2015 10:13 am

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by BBCFAN » Sat Sep 10, 2016 4:02 pm

j-c-c wrote:"I am trying to make it so the truck is a stiff as possible with zero spring wrap.

My theory is with the longer, wider springs it will spring wrap less & be easier to launch."

I don't think spring width is a primary concern for your goals, if handling was, then maybe.

"Stiff as possible" serves little purpose unless you are hauling rocks/dirt.

An asymmetrical leaf (ala mopar style) is a starting point for wrap up concerns, but not a solution I suspect in the 1100hp arena.

Longer front leafs are the wrong direction countering spring wrap.

A PU will as likely benefit from as much weight transfer as you can get, and I'm sure others will chime in on geometry/linkage solutions
Will be pulling a weight transfer sled, so we need to keep hitch height. I was thinking the longer front springs would have more travel when the front of the truck picks up & the rear plants.

User avatar
Alan Roehrich
Guru
Guru
Posts: 2976
Joined: Tue Jul 04, 2006 5:58 pm
Location: Murfreesboro TN
Contact:

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by Alan Roehrich » Sat Sep 10, 2016 5:46 pm

I think swapping a different set of springs and hangers from another truck is probably going to be an extreme amount of work, for little if any gain.

If such as swap is legal, then maybe traction devices and relocated shocks are legal as well, and there is probably a lot more to be gained there.

pdq67
Guru
Guru
Posts: 6454
Joined: Thu Mar 04, 2010 8:05 pm

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by pdq67 » Tue Sep 20, 2016 11:23 am

Have you considered the, "Hotrods to Hell", center push, "truckarm", suspension kits?

http://www.hotrodstohell.net/truckarm/t ... _index.htm

If not mistaken, NASCAR uses this design.

NO rearend windup, but I don't know about anti-squat??

The only downside to using one is usually finding room for mufflers.

pdq67

pdq67
Guru
Guru
Posts: 6454
Joined: Thu Mar 04, 2010 8:05 pm

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by pdq67 » Thu Sep 29, 2016 5:19 pm

I hope I didn't kill this thread when I mentioned the, "Hotrods to Hell", truck-arm suspension.

I think NASCAR uses/requires it.

pdq67

BBCFAN
New Member
New Member
Posts: 28
Joined: Sun Sep 13, 2015 10:13 am

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by BBCFAN » Fri Sep 30, 2016 10:22 pm

I missed it. Been busy working I will look at it & see how it relates.

pdq67
Guru
Guru
Posts: 6454
Joined: Thu Mar 04, 2010 8:05 pm

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by pdq67 » Thu Oct 13, 2016 11:17 pm

Did you find time to look into the HTH truck-arm suspension?

And if you did, what do you think of it?

pdq67

pdq67
Guru
Guru
Posts: 6454
Joined: Thu Mar 04, 2010 8:05 pm

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by pdq67 » Tue Nov 08, 2016 7:18 pm

pdq67 wrote:Did you find time to look into the HTH truck-arm suspension?

And if you did, what do you think of it?

pdq67
Just asking again??

I think that except for muffler install problems, its a cool set-up.

pdq67

Walter R. Malik
Guru
Guru
Posts: 3451
Joined: Tue Jul 24, 2012 11:15 am
Location: Roseville, Michigan (just north of Detroit)
Contact:

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by Walter R. Malik » Sat Nov 12, 2016 12:32 pm

All the Chrysler Super Stock leaf spring cars did exactly that.
http://www.rmcompetition.com
Specialty engine building at its finest.

Olefud
Pro
Pro
Posts: 336
Joined: Thu Feb 21, 2013 11:37 am
Location: Boulder, CO

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by Olefud » Sat Nov 12, 2016 3:38 pm

pdq67 wrote:Have you considered the, "Hotrods to Hell", center push, "truckarm", suspension kits?

http://www.hotrodstohell.net/truckarm/t ... _index.htm

If not mistaken, NASCAR uses this design.

NO rearend windup, but I don't know about anti-squat??

The only downside to using one is usually finding room for mufflers.

pdq67
Squat should be a function of the forward pivot axis and the CoG.

AMXstocker1
Pro
Pro
Posts: 224
Joined: Fri Jun 10, 2016 5:39 pm
Location: Oklahoma City, Oklahoma

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by AMXstocker1 » Wed Nov 16, 2016 4:39 pm

Calvert Racing would be your friend in this instance

pdq67
Guru
Guru
Posts: 6454
Joined: Thu Mar 04, 2010 8:05 pm

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by pdq67 » Sat Nov 19, 2016 3:41 pm

Good old, "slappers", and adjustable coil-over springs on my shocks for the win!!

Just make sure the slappers hit right at the middle of the bottom of the spring eyes and have adjustable hitting "snubber's"!

I made my slappers and they had 1/2" bolts that I could adjust so I could pre-load them side to side. As well as my old junkyard coil-over, overload shock springs I pre-loaded each side at a time.

I spent about a full Sat afternoon to T&T both sides and it would leave straight as a, "rabbit outta the box at the dog track"!!!

pdq67

User avatar
panic
Guru
Guru
Posts: 1924
Joined: Sat Dec 11, 2004 12:04 pm
Location: Ecbatana
Contact:

Re: Designing a Rear Leaf Spring Suspension to hook & not sq

Post by panic » Sat Dec 17, 2016 11:34 am

Longer front leafs are the wrong direction countering spring wrap.

This^

Post Reply