66 F100 Four link Rear Suspension

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RedneckCowboy
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66 F100 Four link Rear Suspension

Post by RedneckCowboy »

Didn't see a thread started on this yet but ive gottten the crown vic frontend done in my truck have now moved on to the rear which is going to be a triangulated four link with coilovers. So has anyone else done a triangulated four link or any other type of four link in one of these trucks? From where the axle is going to sit at ride height there will be 4" between it and the frame. So is the axle really going to move enough to need a step put in the frame or is 4" ok? Pictures would be great if anyone has done this before. And im assuming the frame where the bed mounts should be level in order to make the front and rear of the truck level? Thanks
1966 F250 lwb (parts truck)
1966 F100 swb Chevord
bruceandersson
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Re: 66 F100 Four link Rear Suspension

Post by bruceandersson »

I've never done a 4 link, but always have opinions. I suspect that your truck is not going to be hauling loads. If so then the amount of travel you need is reduced. Most notches are in place in order to be able to slam the truck to the ground. The 4" might be enough as long as this incorporates the bump stops, they will take up about 3" of the travel.
RedneckCowboy
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Re: 66 F100 Four link Rear Suspension

Post by RedneckCowboy »

Should have put this in the original posting but yes the truck will never haul or tow anything, will be purely a show/street rod but not a trailer queen. As for bump stops the 4" of travel is without any, prothane sells 1/2" ones for dropped trucks so I would have about 3 1/2" of travel before it hit the bump stop.
1966 F250 lwb (parts truck)
1966 F100 swb Chevord
cooter
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Re: 66 F100 Four link Rear Suspension

Post by cooter »

most coil overs only have about 3 inches of travel, what are you planning to use for a shock/spring?
why put off till tommorow what you can put off alltogether
luckystiff
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Re: 66 F100 Four link Rear Suspension

Post by luckystiff »

why go 4 link if you aren't going with something that needs a large range of articulation?

i would consider "truck arm" set up before 4 link. but you can get what you're talking with an axle flip over the leafs and a small 2" C notch.
RedneckCowboy
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Re: 66 F100 Four link Rear Suspension

Post by RedneckCowboy »

As of what coil over I'm going to use I haven't found anything inparticular yet but it will be an adjustable one with bump stops built in. Figuring out clearance now so I can decide where to mount the coil overs which will also detirmine which one I will use.
For the seccond question on why I am using a four link without needing the articulation is because it plants the axle better and prevents spring wrap associated with leaf springs with more HP or I would have done a axle flip. And if I was to do the "truck bars" 2 link like c-10s that takes just about as much work as a 4 link so might as well do it.
1966 F250 lwb (parts truck)
1966 F100 swb Chevord
luckystiff
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Re: 66 F100 Four link Rear Suspension

Post by luckystiff »

look at AFFCO high on the list for coilovers. good products at reasonable prices. we used them at the shop. jay was my sales guy but he may only be commercial sales. really good about giving you a good starting figure for spring rate and open to exchanges with no issue should you need to swap them after wards.

QA1 are probably next on my list.

i'll probably swap from my axle flip/blocks to coilovers/4link or truck arm at some point....
LM14
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Re: 66 F100 Four link Rear Suspension

Post by LM14 »

Warning: Long post, deep subject. This is simply my opinion on what I have observed. Your mileage may vary.

I have 30 years experience with coilovers. I have run AFCO, Pro, Carrera (before the QA1 buy out), QA1, Koni, Bilstein and Integra.

I would suggest the QA1 double adjustable. They have a wide range of lengths available. You have a few options on surface finishes. They have a good lip seal and adjustments you can feel when changed. You can easily get valving changed or tailored to whatever you want from the shock. All QA1 shocks are rebuildable except the cheapest dual tube stuff.

My next choice would be Carrera. Chrome shocks but their adjustable stuff is fairly expensive. Since they were bought out by QA1 they haven't lost any of their quality. Most of their steel body stuff is welded and cannot be rebuilt or modified. Their threaded body aluminum stuff is really good and rebuildable.

Pro does not seem to last as long but are probably the cheapest to buy. Not many rebuilders but I worked directly with Pro in Atlanta, GA for what I needed at the time. They were good to deal with and the product was decent. The shafts are a bit smaller than others and their valving tends to be a little softer compared to others (their "5" valving is more like a "4.5" or a "4" from other brands).

Integra makes some of the best stuff out there but be ready to pay for the quality. Only consider the black threaded body shocks if you look at Integra. Best place to get them is Port City Racing. They are the experts on them. Easily rebuildable and easy to customize. Nice stuff.

I wouldn't do Bilsteins. They are good shocks but their coilover kits are the worst in my opinion. There are several rebuilders around the country. All Bilsteins are mono tube gas shocks.

Konis are nice but they can get a little spendy. They also have the most limited finishes available. Very few Koni rebuilders in the USA and not as easily tailored to what you would want. They tend to have very little control in compression and a lot of control in rebound. The theory is that they let the spring control compression and the shock controls the rate of rebound when the spring stretches back out. It works but it takes some learning to make it feel right.

I wouldn't buy AFCOs. They are fairly new to the street rod market. Their race stuff is not up to snuff. They have known lip seal problems and most tend to leak. Since they were bought out by Speedway Motors, the quality has not changed. I have used them off and on over my entire racing career and they had a bigger leaking problem than any other brand of shock. Very few choose an AFCO on a race car anymore. Not like it was in the middle 80's when they started out. The brains behind AFCO shocks went to Integra many years ago and thru Port City introduced the Integra brand of shock. AFCO is behind the curve.

I have spent thousands upon thousands of dollars on coilovers for our dirt late models and modifieds. The QA1 and Integra were the best quality and best value.

Stroke lengths can be had from 3" to 9" fairly easily. You can also get a shorter stroke with a longer shaft (a 7" body with an 8" shaft). It allows a few different mounting lengths. You may find a stroke length but need a longer mounting length, check into just a shaft change. Easy to do.

Mono tube and dual tube are totally different feels. There are also remote reservoir shocks out there, but they really have no place on a street driven vehicle unless it's really high end (IE; $1500-6000 per shock) so I won't address them.

Dual tube shocks are like the older oil filled shocks. The outer tube holds the guts in place but the piston actually runs on a smaller diameter inner tube so it isn't effected by rock dents, etc. These are generally a little cheaper to buy. They will normally be sold as "gas" shocks or "oil filled" shocks. The gas these refer to are actually small gas bags that take up additional air space as shocks move in and out.

The mono tube is usually a gas charged/gas filled shock. The piston runs directly on the inside of the shock body you see. Dent the body and the shock is junk. These are a little tougher to set up since you can have gas pressure pushing against the end of the shock shaft and it creates additional spring rate. They contain a port where gas pressure can be added or removed to change the feel of the shock.

Several companies sell kits to build/rebuild shocks at home (something QA1 started). Don't do it. Even if you are a professional, and you completely understand bleed rates, base valves, piston bores, seals, rod pressures, etc., there is no way of knowing what you are building without a shock dyno. Spend a day running shocks on a dyno and you will find very few are actually what you thought they were. From my experience, QA1, Carrera, Integra and Pro were the best at reproducing results from shock to shock straight out of the box. AFCO and Bilstein usually showed the most difference shock to shock with the same valving as purchased.

Deep subject. I've spent literally hundreds of hours and many thousands of dollars thru the years learning about shocks. We tried most brands out there, spent time with rebuilders and custom valved shocks and had a lot of custom made stuff done thru the years. I actually liked working with the QA1 stuff the best, followed closely by the Integras.

Be glad to answer any shock questions I can and if I can't help you I have several friends with custom shock building businesses and factory training on most brands. I deferred to them to get what I wanted.

My '62 uni will have a triangulated 4 bar with QA1 double adjustable aluminum bodied coilovers on the rear. I am using adjustable lower mounts with billet shock spacers so it doesn't bend the lower mounts.

Springs are the next lesson. More spring producers than shock makes and some surprising results thru the years on spring brands. Again, some of the "names" from a few years are no longer considered anymore. Gotta stay up to date on this stuff.

SPark
1932 Ford 5 window coupe. 302/C4
1962 8V-390/C6 Unibody Short Bed Soon to be Big Window - The Lincoln that never was
2013 F150 Super Crew Eco Boost 4x4
2015 Ford Edge for the little lady, because she said so!
2007 Mustang GT, 4.6-3V/5 Speed. Only 8680 miles on the clock.

More toys, I need more toys!!!
69supercj
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Re: 66 F100 Four link Rear Suspension

Post by 69supercj »

Great info LM14. I'm getting ready to replace/remount the rear shocks on my lowered '66 LWB and I'll probably need a little help. The shocks that are on there now are layed over at a fairly steep angle due to the lowering of the truck and they dont seem to be doing a lot of good. Am I correct in assuming that the efficiency of the shock is reduced as its mounting angle is changed from a straight up mount?
LM14
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Location: Bloomfield, Iowa
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Re: 66 F100 Four link Rear Suspension

Post by LM14 »

Yes.

The effectiveness is measured in the angle from true vertical. Here's a chart that will help with that.

http://static.speedwaymotors.com/images ... rmount.gif

They use a spring calculation in the chart but the numbers are the same for the correction factor for a shock.

Here's an example of some shock valving charts.

http://static.speedwaymotors.com/images ... 2WB735.gif

Every manufacturer of shocks has similar charts. A better chart would list numbers for those valvings in resistance measured per distance traveled over a specific amount of time (force vs velocity). If you get all the shock charts from your favorite brands of shocks, you can compare them much better. It gets a little muddy looking at all the charts and numbers until you get used to it.

Here's QA1 site.

http://www.qa1.net/

SPark
1932 Ford 5 window coupe. 302/C4
1962 8V-390/C6 Unibody Short Bed Soon to be Big Window - The Lincoln that never was
2013 F150 Super Crew Eco Boost 4x4
2015 Ford Edge for the little lady, because she said so!
2007 Mustang GT, 4.6-3V/5 Speed. Only 8680 miles on the clock.

More toys, I need more toys!!!
luckystiff
Posts: 124
Joined: July 28, 2013, 8:23 am
Location: Hickory,NC
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Re: 66 F100 Four link Rear Suspension

Post by luckystiff »

weird........ never had any of the above issues with afco. but have only used them in street apps and as we all know. we had problems out of some others at the shop but i've honestly forgot who they were from at this point.
LM14
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Location: Bloomfield, Iowa
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Re: 66 F100 Four link Rear Suspension

Post by LM14 »

At one point I had 18-20 different AFCO threaded body shocks in 7" and 9" stroke for our pair of dirt late models plus a full set of double adjustables. After standing with the AFCO reps while they were rebuilt in their mobile trailer setup and dynoed, I saw how far off they were even when assembled by professionals. Some were not even close but they fell within the specs at that time. Their double adjustable stuff was all over the place, nowhere near the quality of an Ohlins, Integra or Penske shock. I sold everything AFCO that winter and went to QA1 which was much closer to target specs right out of the box. Even then, all of ours were dynoed and fine tuned before we ever took delivery. Most of our shocks were custom built for a specific corner of the car and a specific track condition. We ran AFCO stuff for years but between missing the target on specs, the awful double adjustable stuff and the seal issues, we walked away from them 5 or 6 years ago. I actually gave 6 or 7 AFCO threaded body aluminum shocks to my shock guy to use as parts that were fresh rebuilt shocks, I had lost that much faith in the product. QA1 also had a short period of time with seal issues on gas charged mono tube shocks. We ran some crazy gas and valving numbers in dirt cars and QA1 wouldn't always take the 175-250# of gas pressures either. We were also running -0- rebound and 12 or 14 compression settings with 250# of gas in a LR shock, hard to keep up with stuff like that and they wear out quickly. QA1 went to a double lip seal and fixed the problem. Maybe AFCO has done the same by now. Our pressures were a lot more than the 60-75# that are in most gas shocks.

Pick a brand and go with it. It's whatever you are comfortable with. You learn a lot with a dyno and an afternoon. Don't believe the advertising hype. Take each one apart and see the quality of the internal components and it will scare you on some big name stuff. I know guys that got all the free shocks they wanted from "Brand X" and they used the "Brand X" body with "Brand Y" internal parts. This is done more than you would think. Also a lot of stuff out there with custom made pistons to split rates and use "Brand X" bodies with "Brand Y" internal parts. It's a crazy business that most on the street guys don't even know exists.

SPark
1932 Ford 5 window coupe. 302/C4
1962 8V-390/C6 Unibody Short Bed Soon to be Big Window - The Lincoln that never was
2013 F150 Super Crew Eco Boost 4x4
2015 Ford Edge for the little lady, because she said so!
2007 Mustang GT, 4.6-3V/5 Speed. Only 8680 miles on the clock.

More toys, I need more toys!!!
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