Duff 4-Link Street Version

JWMcCrary · Jan 14, 2020

jasonmcc said:
What is that opinion based on?

He stayed at a Holiday Inn Express

bronconut73 · Jan 14, 2020

rpmgarage22 said:
We don’t do direct work for customer vehicles at Duff’s. But, my shop is only 30 minutes from the office.

I’m the “Mike” you get when you call Duff’s for technical support. I’ve been there for five years.

I cut my teeth on custom 4-links for Minitrucks and lowriders, beginning in the ‘80s.

If you are interested in having work done, I would appreciate your consideration. Feel free to email me and we can go from there.

You had me at,

"4 links for Mini Trucks in the 80's...."

We must be about the same age.

wsager · Jan 14, 2020

bronconut73 said:
You had me at,

"4 links for Mini Trucks in the 80's...."

We must be about the same age.

Did you also have a 1985 S-10 ext cab with a SBC? Exhaust note kept the deer from the roads.

68ford · Jan 14, 2020

Yeller, this is the type of vehicle I have experience with.
https://images.app.goo.gl/t4U929raoPFhJmno7
Obviously they are in a perfect world where they can do whatever they want and put the output shaft wherever they want. But I know in these applications, the geometry let's the pinion angle radius match the drive shaft and the plunge is usually less than 1in over 36in wheel travel. They also have perfect antisquat and all that, to where having over a 1000 foot pounds of torque down the driveshaft has no affect or input on the suspension raising or squaring. Drive shaft angle is also almost the same as the lower links. Everything about the duff kit seems abnormal. I'd like to see it performs in a high horsepower application under acceleration and cornering under power

jasonmcc · Jan 14, 2020

Alright, I ordered it so I'll post pics as I go as well as a review once I get her on the road.

Yeller · Jan 14, 2020

68ford said:
Yeller, this is the type of vehicle I have experience with.
https://images.app.goo.gl/t4U929raoPFhJmno7
Obviously they are in a perfect world where they can do whatever they want and put the output shaft wherever they want. But I know in these applications, the geometry let's the pinion angle radius match the drive shaft and the plunge is usually less than 1in over 36in wheel travel. They also have perfect antisquat and all that, to where having over a 1000 foot pounds of torque down the driveshaft has no affect or input on the suspension raising or squaring. Drive shaft angle is also almost the same as the lower links. Everything about the duff kit seems abnormal. I'd like to see it performs in a high horsepower application under acceleration and cornering under power

Yes that’s a whole other world of Disneyland that is an awesome place to get to be, and I have spent some time there. I watched them closely go through their changes in the late 80’s and 90’s where they made massive technological advances and really began to get dialed in. I can attest the Duff system drives and handles more predictably with big power than leafs and a torque tamer or what ever your choice of single link torque control you choose to use. But with big power it does need shock tuning, just like anything else that gets many times the design power input it becomes more of a race vehicle and needs to be tuned as such, not that it’s not possible or even can’t be a DD but they require more work to be dialed in. And remember those race trucks are HUGE a 92” bronco is never going to be in the same ballpark, and I am familiar with your racing exploits, I’m envious of your experiences.

jasonmcc · Jan 14, 2020

As always thank you for sharing your knowledge guys

yakelys69 · Jan 14, 2020

jasonmcc said:
Alright, I ordered it so I'll post pics as I go as well as a review once I get her on the road.

Cool looking forward to seeing your upgrade and review.

bronconut73 · Jan 15, 2020

wsager said:
Did you also have a 1985 S-10 ext cab with a SBC? Exhaust note kept the deer

...Exactly.......

rpmgarage22 · Jan 15, 2020

bronconut73 said:
You had me at,

"4 links for Mini Trucks in the 80's...."

We must be about the same age.

Awesome. I will be 49 in March...

Still love those MiniTrucks...but the kids that drive them today don't have the $$$ to get me to build them... Some things never change!

rpmgarage22 · Jan 15, 2020

wsager said:
Did you also have a 1985 S-10 ext cab with a SBC? Exhaust note kept the deer from the roads.

Well...you got me there:

'83, single cab, with 383 stroker and a TH350...

Best thing about that one...well, two things-

1) I learned about cooling systems!
2) I learned that good brakes were just as, or more, important than the ability to go fast in a straight line!

If I had only known how much that would benefit me when I started working on Broncos!!!

bronconut73 · Jan 15, 2020

rpmgarage22 said:
Well...you got me there:

'83, single cab, with 383 stroker and a TH350...

Best thing about that one...well, two things-

1) I learned about cooling systems!
2) I learned that good brakes were just as, or more, important than the ability to go fast in a straight line!

If I had only known how much that would benefit me when I started working on Broncos!!!

'87 Extended Cab
At 17 I pulled the V6 with only 66k on it. I put those miles on it in just over 16 months driving back and forth from Orlando to Jax Florida.

While it still looked new it had a,
350 sbc
TH700 OD

I learned how to do really long burn outs....lol....

She was an insane tire spinner!

Used to put a few bags of concrete in the right rear corner of the bed. It made a remarkable difference for only about 160 pounds.

I cut my teeth on that shit.
Loved every damn minute of it.
My parents and my S-10 were not friends, lol.

My poor eb was relegated to daily driver status back then...lol.

rpmgarage22 · Jan 15, 2020

bronconut73 said:
'87 Extended Cab
At 17 I pulled the V6 with only 66k on it. I put those miles on it in just over 16 months driving back and forth from Orlando to Jax Florida.

While it still looked new it had a,
350 sbc
TH700 OD

I learned how to do really long burn outs....lol....

She was an insane tire spinner!

Used to put a few bags of concrete in the right rear corner of the bed. It made a remarkable difference for only about 160 pounds.

I cut my teeth on that shit.
Loved every damn minute of it.
My parents and my S-10 were not friends, lol.

My poor eb was relegated to daily driver status back then...lol.

Haha!

I took the stock rear bumper off, built "boxing plates" for it, filled it with three bags of Quikrete, welded it up, and bolted it back on. Ran 295/50/15's with 4" dropblocks and a steel bedcap... It would make white smoke and black lines. I tried putting Lakewood "slapper bars" on it...but it was so low that I couldn't get over a speed bump without them digging in.

I had a .292/.480 Lunati "Street Thumper" cam in it. It had NO vacuum. Couldn't stayed stopped at a red light unless you popped it into neutral or park. It would pull right out from under its own brakes...

I bent up a "roll cage" out of exhaust tubing, painted it black, and put black PVC pipe insulation from Sears on it...just so I could mount five point race harnesses.

I was able to do it all for under $5k, in 1996. First set of Flowmasters I ever owned. Took me 17 evenings and two weekends to do it. Back then, there were no "V8 swap kits". Of course, we walked 5 miles to school, uphill both ways...too!

bronconut73 · Jan 15, 2020

rpmgarage22 said:
Haha!

I took the stock rear bumper off, built "boxing plates" for it, filled it with three bags of Quikrete, welded it up, and bolted it back on. Ran 295/50/15's with 4" dropblocks and a steel bedcap... It would make white smoke and black lines. I tried putting Lakewood "slapper bars" on it...but it was so low that I couldn't get over a speed bump without them digging in.

I had a .292/.480 Lunati "Street Thumper" cam in it. It had NO vacuum. Couldn't stayed stopped at a red light unless you popped it into neutral or park. It would pull right out from under its own brakes...

I bent up a "roll cage" out of exhaust tubing, painted it black, and put black PVC pipe insulation from Sears on it...just so I could mount five point race harnesses.

I was able to do it all for under $5k, in 1996. First set of Flowmasters I ever owned. Took me 17 evenings and two weekends to do it. Back then, there were no "V8 swap kits". Of course, we walked 5 miles to school, uphill both ways...too!

Where is the damn "like button" at? Haha

jasonmcc · Jan 31, 2020

Progress so far...

rguest3 · Jan 31, 2020

Jason - I'm looking forward to seeing how your 4-Link turns out.

I see you mounted the Rear Coil Buckets even with the Top of the Frame. What springs do you have up front? Soft Top or Hard Top? Bumpers? Drivetrain in now with body installed?

Did you mount the rear buckets at the Factory 92 Inch Wheel Base or slightly farther Back?

Great pictures by the way.

rpmgarage22 · Jan 31, 2020

Thank you for the progress pics, Jason!

Coming along great...

b56tc · Jan 31, 2020

welds are beautiful. Pure art.

jasonmcc · Jan 31, 2020

rguest3 said:
Jason - I'm looking forward to seeing how your 4-Link turns out.

I see you mounted the Rear Coil Buckets even with the Top of the Frame. What springs do you have up front? Soft Top or Hard Top? Bumpers? Drivetrain in now with body installed?

Did you mount the rear buckets at the Factory 92 Inch Wheel Base or slightly farther Back?

Great pictures by the way.

The rear buckets are actually even with the bottom of the frame. We tacked them up and once we put the body back on with hard top, roof rack, bumper, spare tire we adjusted them a little higher. We also moved the rear back 2” to center up in wheel well. We should have new Tom woods drive shafts in this week or early next.

A few more pics...

yakelys69 · Jan 31, 2020

Looking Great!

Duff 4-Link Street Version

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