the pro4 short course trucks ran gm stuff before they went all fancy x-trac, wiesman, weddle, etc.
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Ifs 101
- Thread starter patooyee
- Start date
the pro4 short course trucks ran gm stuff before they went all fancy x-trac, wiesman, weddle, etc.
Tech Tim
Your AD Here....
Yep, that's one of the things that got us looking at them.
Tech Tim
Your AD Here....
Dang, the different UBH bolt pattern is one thing I didn't notice on your earlier knuckle pics. Wonder why GM would change the bolt pattern?
The pre-2011 knuckle uses the standard 4 bolt pattern, so you can use the GM UBH, the Ford UBH, the Spidertrax UBH.
Wilson
Newb
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That is great info and opens up for upgrades
You're talking about the 4 bolts that attach it to the knuckle? I wasn't aware that there was a standard? The pre-2005 Ford pattern is different than the post-20005 Ford pattern, isn't it? It has to be to accommodate the massive bearing size increase I think. Spidertrax wouldn't need two different builder bells if they were the same pattern. The central hub diameters probably differ as well, which matters a lot to index it into the bore. So you're saying Ford and Chevy agreed to use the same pattern at some point?
Now I wish I had models of the older UB's to measure.
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Isdtbower
In for Tech
That does seem to be a little ovekill on the 1" plate. Maybe 1/2" is sufficient with a good inside Bell. But what I have been around, and noticed other places, has been hardened for lightness.Building a new upright was usually a huge hit and not hardened. Usually the bottom omni has minimal location choices. The top Omni is a different story and why a new upright. It seems like that would change with portals.
Seeing all 4 wheels bent or broke after a race is much more common. For a rec guy replacing a wheel is always a cheaper alternative. Choose with that in mind. Generally a casting will break. A forging can be stronger and will bend more...depending on thickness and some heat treatment. But some forgings will bend easily and not leave you stranded unless it contacts the caliper. Wheel design gets pretty specialized when clearing the bigger rotors and calipers. I had to drop from 13" to 12.5" rotors to clear some prototype forged wheels. Some are managing a 14" rotor in a 17" wheel!! The more backspace the smaller the inside diameter generally, or a smaller drop center making tire changes tougher.
Remember to IFS design from the wheel in.........I couldn't start my actual build until I received the actual prototype wheels. Some of that was my choice of VW Wide 5 pattern and lack of aftermarket options. They came in with 1/4" less backspace than anticipated. but easily fixed with a small change in KPI.
I see 20" wheels becoming more popular with the move to 42"+ tires and the need for more brake over sidewall distance. Lots of weight disadvantage there though. Tires and wheels . Just looking to the future of the high end.
Edit: I noticed that OCM didn't use a bell around the CV, so probably the choice for the thick front plate. Neat design as it makes boot clearance more reasonable. vertically.
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arse_sidewards
Contrary to everything
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Ford ('05 up) and Dodge (year unknown, was discussed in the SD60 tech thread on the old site) use the same bolt pattern, different bore. I don't know if the bolt pattern or either bore matches GM.
These bearings are being sources from outside suppliers. It's quite common for the engineers to ask vendors to recommend reasonable middle of the road values for stuff. For something as trivial as a bearing bore I can see 2/3 automakers being like "fuck it, just use the manufacturer's recommendation" since that's one less thing to have to think about.
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Isdtbower
In for Tech
The older Ford and maybe some of these Unit Bearings can be significantly upgraded by replacing the inside bearing sleeve with a hardened one....
Edit: See Tech Tim below
Edit: See Tech Tim below
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AgitatedPancake
Frobot
Ahhh is that what caused the versions with the huge 4 prong spanner nut on the back to loosen up over time? I remember conversations about those loosening back on the old board, but don't know if I ever heard the actual cause beyond some theory of spindle stretching after being bored for 35 spline
Tech Tim
Your AD Here....
Yes, the 4 bolt pattern on the UBH and yes the pre-2005 Ford, that was the standard for D60 swaps for years.
IDK if the OD bore is different between the GM and the Ford. We had finished a 6" lift on a GM truck and had the factory knuckles sitting on the workbench, I grabbed a Ford <2005 UBH and dropped it right in with the 4 bolts lining up. So I grabbed an old Spidertrax UBH we had and it too dropped right in.
It was the spindle that would stretch over time. We saw it with stocker and bored UBHs. The factory UBHs under a Super-Duty seemed to go 75-100K miles before they needed to be replaced. Those who used their trucks hard were loosing them in 50K (loggers, miners, ranchers etc.). You could tighten them up, then you'd have to stake 'em or tack 'em. Spidertrax really worked hard at making the Ford UBH a nice piece, eventually replacing the spindle with a cromo one of their own making.
It appears that I'm going to have to get a whole separate education on Omni-Balls before I can make any serious design considerations.
https://www.kartek.com/parts-categories/rod-ends-heims-and-uniballs.html
I need to figure out the difference between all these series, why one would choose one over the other, etc. I'll compile my list of questions over the next couple of days, but if anyone has a quick rundown that they can give that would be great.
https://www.kartek.com/parts-categories/rod-ends-heims-and-uniballs.html
I need to figure out the difference between all these series, why one would choose one over the other, etc. I'll compile my list of questions over the next couple of days, but if anyone has a quick rundown that they can give that would be great.
Weasel
Red Skull Member
Just depends on the materials used and overall strength.
Isdtbower
In for Tech
Another link to info. FK spherical bearings. I think if you focus on the COM-HT and WSSX-T these are what most run with. Aurora is another supplier but generally not competitive price wise but Everyone has old parts on the shelf . You can find some deals. I found printing the pages and making notes with misalignment's will make it easier as you go along.
https://www.fkrodends.com/products/spherical-bearings/
https://www.fkrodends.com/products/spherical-bearings/
Tech Tim
Your AD Here....
The comm series are typically the least expensive and will work just fine in a trail application.
The wide series being able to bear a higher load with less possible misalignment as compared to commercial? Is that the general concept there?
id do 3/4" in the inner lower pivots, 5/8" in the uppers inners (id probably do 3/4" there so everything matched) and 3/4" at the spindle.
Poke
I’m condescending
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I have a scaling question on IFS. Can the measurements be scaled up and down proportionally?
could I take a known, good IFS front and make a bigger or smaller car work, the same. For example
scale down a TT front end to a smaller buggy
or
take rzr ifs specs and scale it up to a full sized vehicle?
could I take a known, good IFS front and make a bigger or smaller car work, the same. For example
scale down a TT front end to a smaller buggy
or
take rzr ifs specs and scale it up to a full sized vehicle?
Isdtbower
In for Tech
I think you could. Remember to scale the tires and wheel backspace. And don't cheat yourself on the Arm inner mount widths. Those are on a pivot line so you can do what you need to do. Steering and outer hub sizing are still gong to be a challenge but you will get it. When you scale up, every dimension will have to be looked at from many angles. And your offroad purpose might not agree to what you are copying. A good place to start, but, I bet that the end result will be different. I, personally, would not copy a RZR to full size. Plenty of hints why in 42 of these pages.
It WOULD be good drill to understand what others have done for their particular application. Good to steal some of their thoughts.
KarTek recommends staying away from com series because they don't make misalignment spacers with the same ball diameters to fit them. They say WSSX or HIN is what I should be after.
EDIT: Looking at HIN, the sizing doesn't go very big. That pretty much leaves WSSX.
OK, here's my understanding of the FK series offerings:
- COM: Economical but uses a different ball dia. than the others so none of the KarTec mis. spacers fit them. Are there others that do?
- FKS: Narrow bodies for tight spaces but with lower load ratings as a result. Probably not ideal for abuse?
- WSSX: Most commonly used / has the widest selection of cups, mis. spacers, etc.
- AIN: High-end, HD, uses premium metals and tolerances. Least price-friendly.
- HIN: Highest available misalignment out of the box, basically because it has the spacer built into it. Limited sizes.
- GEZ: "Fractured Race Series." No clue, but sounds expensive. LOL.
Tech Tim
Your AD Here....
For the most part yes. If you like the geometry and handling, scaling an IFS up would pretty much give you that same geometry with more travel. It could also potentially exaggerate any flaws in the geometry. Longer arms means more leverage.
I would also agree with Isdtbower, make sure to scale everything up accordingly from the wheel/tires to the inner CV flanges and a-arm pivot point. Don't forget the steering points as well.
Poke
I’m condescending
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Thank you. I’ve got a bad, expensive, but fun idea!
Weasel
Red Skull Member
FKS is what I'd be looking at. According to your link from kartek the FKS 3/4 has a much greater radial load rating then the WSSX does.
You're right. They call it the "narrow" series so I assumed it would have less surface area to spread a load. But they are higher strength, so apparently I don't have a full understanding of what I'm looking at. But FKS shares the same ball diameters as COM which means no mis. spacers.
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Weasel
Red Skull Member
correct not high mis-alignment. So you could just upsize and run a mis-align spacer.
I feel like I'm missing something. The FKS series stops at 1.5". So not much up-sizing available. They also feature one of the lowest misalignments and, since high mis. spacers aren't available, wouldn't you be stuck with it?
Provience
Kill!
high(er) mis alignment spacers have a deeper kneck down to allow for more angle and that results in less diameter and less overall strength. same/similar concept to fine thread bolts having higher strength rating than coarse thread bolts, because the minimum diameter is larger on the fine thread.
if that what you are talking about?
Weasel
Red Skull Member
yep.
No, I don't think so. Let's review terms as I understand them. Maybe I don't understand them correctly:
High-Misalignment Spacer - A spacer that has a radiused ball at the base where it coincides with the edge of the ball to allow the spacer itself to travel into the the body of the joint as well as the ball to travel further in into the body than otherwise would be physically possible. The radius of the ball on the spacer must be equal to the radius of the ball in the joint or the spacer doesn't function properly. If the radius is too large it damages the body of the joint as it travels and if it's too small it allows dirt in through the gap. On the left is an example of too large a radius:
Misalignment Spacer - A spacer that does not have the radiused base where it coincides with the ball. These really only reduce bolt size and increase clearance for objects near the joint as it twists. They do not allow any additional misalignment beyond that which would be allowed if just a bigger bolt were in the joint instead of the spacer.
So for high-mis spacers to work, their radius must match the ball's radius. COM and FKS have different radius balls than WSSX. As far as I can tell, CarTek does not make high-mis spacers with the correct radius for COM and FKS series balls. [EDIT: They don't, I called and confirmed.] They only make them to match WSSX. If you use a WSSX high-mis in a COM or FKS joint you get the pic on the left above. I've not found anyone that makes high-mis spacers for COM / FKS yet. Maybe it's out there ... ?
I think that Weasel was suggesting that I use FKS for it's high strength. But I noted that their misalignment was poor and I can't find high-mis spacers for them. (I think I may have goofed and left the "high" out, which may have been part of the confusion.) He suggested that I simply up-size the FKS joint and run mis-spacers to compensate. But the two problems are that they have very few up-sizes available and, as noted above, a mis-spacer doesn't give any more misalignment. (A high-mis spacer would be needed to do that.) So that's where his suggestion doesn't make sense to me. One of us appears to have a flawed concept of something. (Probably me.)
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