Help: Suspension gurus look inside please

rgullett83

rgullett83

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Kind of got a late start this year, this only the 4th pull on this truck this year. Any ways, has a Dana 60 under the front of it supported by coil springs, and a triangulated four link (Home built setup). Drives and rides awesome on the street, but the truck is a dedicated puller now. This was the first pull where the axle has hopped that violently, it has hopped before but not like this. Looking for some advice on ways to help prevent this. It has a set of Afco shocks up front with adjustable compression and rebound, I am not for sure how they were set up, I would have to ask the driver. I will get some pics of the front end later, so you all can see how its setup. I am wondering if a true four link would help control this better:confused:
 
Chevy1925

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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hes got some toe issues IMOP. And that combined with a tacky track can make for a jumpy ride.

How much nitrogen pressure is he running in the shocks? Compression seems light in the shocks too but all this cant be adjsuted till the toe is fixed.
 
juddski88

juddski88

Freedom Diesel
Jul 1, 2008
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Chesterfield, Mass.
i've seen few triangulated links work up here, mostly all have gone to 4-link. also, what I've always been taught about the front suspension stiffness on a 4 link front is make it as soft as possible, just enough to keep the tires down.
 
rgullett83

rgullett83

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Chevy1925 said:
hes got some toe issues IMOP. And that combined with a tacky track can make for a jumpy ride.

How much nitrogen pressure is he running in the shocks? Compression seems light in the shocks too but all this cant be adjsuted till the toe is fixed.
Click to expand...

Yes there are some toe issues, the tie rod is bent. Thinking about just building one, any suggestions, on tubing size and heims to use? I am not for sure on the spring rate. When we did the swap he ordered 4" lift coils for a super duty.
 
rgullett83

rgullett83

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jimdmax said:
How stiff are the coils.
Click to expand...

with roughly 800LBs hanging on the front, you can still jounce the truck well. I will see if I can get him in here to talk about how the shocks were set up. The tie rod may mave been bent before, but it is really bent after yesterdays pull, and it was a pretty hard track as well.
 
SmokeShow

SmokeShow

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Nov 30, 2006
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Shoot, the toe in looked as bad as an IFS truck without sleeves. What's the steering geometry? What D60 is under it ball joint or king pin?

It appears to want to pull the front end up too much perhaps making the front too light & giving you toe in issues which goes into that fit. What's the hitch & rear suspension setup?
 
rgullett83

rgullett83

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SmokeShow said:
Shoot, the toe in looked as bad as an IFS truck without sleeves. What's the steering geometry? What D60 is under it ball joint or king pin?

It appears to want to pull the front end up too much perhaps making the front too light & giving you toe in issues which goes into that fit. What's the hitch & rear suspension setup?
Click to expand...


King pin 60 out of a late 70s ford. Right now we have blocks in the rear, that allow 1" of travel, I will shoot some pics of the steering and hitch setup here shortly
 
rgullett83

rgullett83

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here are a few the front end, will get some more later
 

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durtymax

durtymax

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Jun 17, 2011
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Chevy1925 said:
hes got some toe issues IMOP. And that combined with a tacky track can make for a jumpy ride.

How much nitrogen pressure is he running in the shocks? Compression seems light in the shocks too but all this cant be adjsuted till the toe is fixed.
Click to expand...

I can see what your saying, once the tie rod bent, the toe in was only making it worse.
The nitrogen pressure is whatever afco sends them with. compression was as stiff as they go with all the rebound taken out.
 
durtymax

durtymax

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SmokeShow said:
Shoot, the toe in looked as bad as an IFS truck without sleeves. What's the steering geometry? What D60 is under it ball joint or king pin?

It appears to want to pull the front end up too much perhaps making the front too light & giving you toe in issues which goes into that fit. What's the hitch & rear suspension setup?
Click to expand...

hitch is just a reese style hitch, nothing trick. 26" high. that was the least amount of weight Ive yet to run on the front end. only because the scales said I was 200 over. they allowed 100 over so i had to take one weight off.
 
Chevy1925

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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rgullett83 said:
Yes there are some toe issues, the tie rod is bent. Thinking about just building one, any suggestions, on tubing size and heims to use? I am not for sure on the spring rate. When we did the swap he ordered 4" lift coils for a super duty.
Click to expand...

I Would use at the very least .120 wall 1 3/4 chromoly with 3/4 heims. You could also get away with .250 wall DOM but i wouldnt go any thinner in DOM than that. i think .188 chromoly would be plenty strong. Make sure the heims are the high dollar style ones (not the ones you get a tractor store). i believe they run about 40 bucks a peices. RuffStuff is having a blow out on the good heims with bungs and misalignment spacers right now for 50 bucks a pair! id jump on that if you can

durtymax said:
I can see what your saying, once the tie rod bent, the toe in was only making it worse.
The nitrogen pressure is whatever afco sends them with. compression was as stiff as they go with all the rebound taken out.
Click to expand...

You dont want to run the least amount of rebound if can. you want that front end stiff like the rear so max both out and see what it does if you havent already. taking the rebound all the way out lets the front end "fall" very fast after it compresses which then allows tire bounce to compress the suspension once again. it only gets worse as the tires spin too. Even with compression maxed it still will let the axle move up, just not as much as before, so you need the rebound to help you out some in controling the axle. you want it to follow the ground and hold it there if you see what im saying
 
durtymax

durtymax

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[/QUOTE]You dont want to run the least amount of rebound if can. you want that front end stiff like the rear so max both out and see what it does if you havent already. taking the rebound all the way out lets the front end "fall" very fast after it compresses which then allows tire bounce to compress the suspension once again. it only gets worse as the tires spin too. Even with compression maxed it still will let the axle move up, just not as much as before, so you need the rebound to help you out some in controling the axle. you want it to follow the ground and hold it there if you see what im saying[/QUOTE]

ok lemme make sure we are saying the same thing. i should have worded it different. when i said i had all the rebound taken out, i meant it was rebounding as slow as it can. I also have it compressing as slow as it can, i.e. stiff. Is that what you are saying also?
 
B

bubba2400

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Jul 19, 2009
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Union Grove, WI
Shock placement. Also, something with those coils out of the newer super duties just makes them bouncy. I believe they are just a little stiff for just a dedicated pulling rig. Nice setup though:thumb:
 
durtymax

durtymax

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Jun 17, 2011
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bubba2400 said:
Shock placement. Also, something with those coils out of the newer super duties just makes them bouncy. I believe they are just a little stiff for just a dedicated pulling rig. Nice setup though:thumb:
Click to expand...


Shock placement, as in they need to be more towards the front for better leverage?
And you think the newer coils are actually to stiff??
 
Chevy1925

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
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durtymax said:
ok just checking, thats how I had em set in the video

sorry bout the confusion. And thanks for your input
Click to expand...

no prob

durtymax said:
Shock placement, as in they need to be more towards the front for better leverage?
And you think the newer coils are actually to stiff??
Click to expand...

yes toward the front so the shocks are not working so much off a leverage point. it will essencially give you "stiffer" compression and rebound.
 
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