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Re: Tall vs. Short Spindles
[Re: Rick_Ehrenberg]
#17892
11/04/05 11:00 PM
11/04/05 11:00 PM
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Joined: Sep 2003
Posts: 19,700
north of coder
moparx
"Butt Crack Bob"
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"Butt Crack Bob"
Joined: Sep 2003
Posts: 19,700
north of coder
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rick, thanks for the response. but now, if i want to reduce "bump" , which way do i go[raise/lower]with the tie rod ? and also, by how much to gain approximately ????? in my situation, i have stayed within a tolerance of .005-.015 on all of the components i have fabbed so far, [including the positioning of same] & i would like to keep the bump within the same specs if it's possible. i realize this may be getting slightly off topic, but in order to correct "bump", others may find this info usefull as well. 
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Re: Tall vs. Short Spindles
[Re: AndyF]
#17893
11/05/05 02:34 AM
11/05/05 02:34 AM
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Joined: Jan 2003
Posts: 5,395
Pikes Peak Country
TC@HP2
master
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master
Joined: Jan 2003
Posts: 5,395
Pikes Peak Country
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Quote:
I have been asked by one company to design a dropped forged aftermarket Mopar knuckle that is even taller than the FMJ knuckle. If that project ever happens just imagine the debate on this board!
If that happens I'll buy a set from you. Make a set with a 2" drop in them, and you won't be able to build them fast enough.
I've heard mixed reviews on Fatmans spindles, all of it from street rodders. They accomplish the drop alright, but don't appear to be real stout, nor particularly decent looking. However, that info is a couple years old so they may have come up with a new or better design since then.
Other brands have been converting to taller spindles for handling improvements for decades. It only seems to be in the Mopar camp that this is an ongoing debate.
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Re: Tall vs. Short Spindles
[Re: TC@HP2]
#17894
11/05/05 09:40 AM
11/05/05 09:40 AM
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Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
patrick
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
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one thought on the whole toe issue:
at full extension you have .186 degrees toe-in and at full dive, you have .013 degrees toe out. when you go around a corner, what happens? the outside wheel compresses, the inside extends. so what does this show? by reducing toe-in on the outside, and increasing it on the inside, that's effectively not steering the wheels quite as far (note, we're talking tenths of a degree), so I would assume the car would understeer slightly more. but at the same token, the higher roll center, improves roll resistance slightly, so the car should lean slightly less going around a corner, so in the end, it should pretty much be a wash.
around here, you can't find A bodies in a junkyard, let alone disc brake ones, so the A body spindles fetch $150-300. but there's dippy's and 5th ave's everywhere, and you can get the spindles from a yard for about $20-30. in fact, I wanted the large rotor caliper brackets for my car, and the yard said $30. I couldn't get them off with a wrench, so they lifted the car up, and cut the upper and lower control arms, and let me have both assemblies (spindle, adapter, caliper, rotor, and 15x7 wheels!) for $30. this was off an '80 or 81 5th ave (R body)
1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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Re: Tall vs. Short Spindles
[Re: Rick_Ehrenberg]
#17895
11/06/05 02:30 AM
11/06/05 02:30 AM
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Joined: Jan 2003
Posts: 27,485
So Cal
autoxcuda
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,485
So Cal
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Ok, you sucked me in again... ;->
Sorry about that.
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You're missing the crux of the problem. Sure, I have no doubt whatsoever that for track-only cars, specific applications, etc., there are setups better that OEM/dead stock. But do you really think the person who asked if this was a good bolt-on swap is gonna do that?
No, I agree. Like I ageed before
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Do you think even one in 100 alignment shops knows how (or will take the time) to do that?
No. Agree again.
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Or, will the guy who's doing the swap, who is using the Volaré knuckles to save $$$, wants to spend 5X what he saved on the knuckles at a race chassis shop?
Nope.
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Megadittos on heim joints for the street. Same deal. Awesome, easy to adjust, quick to fabricate links and arms for race cars, be they drag, circle track, or road course. But about ase useful as teats on a bull for street use! (They pound out from road shocks, and most that I've seen have no provision for lubrication and/or environmental seals.) I highly doubt (a guess) that the typical ones are anywhere near as strong a a stock tie-rod end. Good thing they are (when installed correctly) fail-safe!
Agreed. Don't know how much Peter drives it. Just giving possible options. Trying to look outside the box.
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One detail (?) that has been conveniently glossed over: When the tall knuckles were introduced (73), if they were better / lighter, and did the job, why didn't the Highland Park guys specify them for A and E cars, too? Mega-corporations love standardization! Because - from their lips to my ears - they had a "negative impact on the geometry that we had worked so hard to get right." Remember, these knuckles were only designed out of sheer necessity, because the rubber-isolated K-members resulted in a taller overall package, incl. higher upper control arm pivot points.
Like I said before. It's not a competition between the two spindles issue. Because IMO they're each running in "different" races. OEM setups have tons of criteria and contraints to follow in thier designs. AND most the people wanting to use F-body spindles for the lack of finding A-body spindles to do simple disk swaps have the same criteria and constaints.
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Re: Tall vs. Short Spindles
#17896
11/06/05 02:46 AM
11/06/05 02:46 AM
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Joined: Feb 2003
Posts: 7,982
Scranton, PA
Montclaire
master
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master
Joined: Feb 2003
Posts: 7,982
Scranton, PA
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Quote:
I'll bet a donut that in 73 the A body was already slated to go bye bye and the vehicle that became the F body was being designed. CC wasn't gonna spend any money redoing or reengineering or verifying the A body front suspension for a new spindle. So they stuck discs on it basically using a modded drum spindle that was know to be satisfactory.
That doesn't make sense. The sole reason that the taller spindles were introduced was to return the suspension on iso-k cars back to the proper geometry found in earlier models. This gets confusing because the bent t-bar setup of the F-bodies and others is an engineering nightmare and also causes bumpsteer problems. Some chrysler engineers actually left the company over the whole bent t-bar thing, as they felt it was detrimental to the good reputation their design(s) had developed over the years.
Now that I'm thinking about this though, what would happen of you installed the k-frame spacers from the 73 and on iso-k cars onto a 72 or older car with the taller spindles? Shouldn't that return things to the proper geometry, and everybody would live happily ever after with their cheap-o taller knuckles and aluminum k-frame spacers?
-->Rick, I'd like to talk to you about the POR pro rally, if you remember the article you did on it years ago. You campaigned a plymouth turismo and got a DNF after sucking mud down the air intake. I'm thinking of doing something similar and was looking for some information, please PM me if you'd like to discuss it.
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Re: Tall vs. Short Spindles
[Re: Montclaire]
#17897
11/06/05 04:42 AM
11/06/05 04:42 AM
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Joined: Jan 2003
Posts: 27,485
So Cal
autoxcuda
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,485
So Cal
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Quote:
Now that I'm thinking about this though, what would happen of you installed the k-frame spacers from the 73 and on iso-k cars onto a 72 or older car with the taller spindles? Shouldn't that return things to the proper geometry, and everybody would live happily ever after with their cheap-o taller knuckles and aluminum k-frame spacers?
The T-bars would end up angled, the driveshaft pinion angles changed, fan shroud offset. I also doubt the spindle was heighten JUST for the iso-k-frame.
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Re: Tall vs. Short Spindles
[Re: autoxcuda]
#17898
11/06/05 02:10 PM
11/06/05 02:10 PM
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Joined: Feb 2003
Posts: 7,982
Scranton, PA
Montclaire
master
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master
Joined: Feb 2003
Posts: 7,982
Scranton, PA
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Quote:
The T-bars would end up angled, the driveshaft pinion angles changed, fan shroud offset. I also doubt the spindle was heighten JUST for the iso-k-frame.
I suppose it's more trouble than it's worth, and now that you said that, I'm guessing that the t-bar mounts are lower in 73-74 b-bodies. I've never owned one and they aren't the most popular body style, so I can't say for sure.
How can you say that you doubt the spindles were heightened just for the iso-k? That's exactly why they were heightened, to maintain the geometry of the non-iso cars.
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Re: Tall vs. Short Spindles
[Re: Clair_Davis]
#17900
11/06/05 08:00 PM
11/06/05 08:00 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Re: Tall vs. Short Spindles
#17901
11/06/05 08:01 PM
11/06/05 08:01 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Re: Tall vs. Short Spindles
#17902
11/06/05 08:01 PM
11/06/05 08:01 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Re: Tall vs. Short Spindles
#17903
11/06/05 08:02 PM
11/06/05 08:02 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Re: Tall vs. Short Spindles
[Re: Montclaire]
#17904
11/06/05 10:40 PM
11/06/05 10:40 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Quote:
That doesn't make sense. The sole reason that the taller spindles were introduced was to return the suspension on iso-k cars back to the proper geometry found in earlier models. This gets confusing because the bent t-bar setup of the F-bodies and others is an engineering nightmare and also causes bumpsteer problems. Some chrysler engineers actually left the company over the whole bent t-bar thing, as they felt it was detrimental to the good reputation their design(s) had developed over the years.
Now that I'm thinking about this though, what would happen of you installed the k-frame spacers from the 73 and on iso-k cars onto a 72 or older car with the taller spindles? Shouldn't that return things to the proper geometry, and everybody would live happily ever after with their cheap-o taller knuckles and aluminum k-frame spacers?\
You are making one critical error in your thinking. The upper control arm inner pivot in the transverse torsion bar suspension is NOT mounted on the unibody like the earlier Mopars. It is mounted to the K member. Chrysler could have made the distance between the UCA and LCA inner pivots any spec they wanted, they could have matched the early torsion bar suspension specs in a heartbeat.
The rubber isolators used between the K member and the body on the later Mopars have NO bearing on spindle height, period. Those rubber isolators were used for one purpose only, to smooth out the ride as felt from the passenger compartment. Obviously handling wasn't an issue here. And yet they saw fit to heighten the spindle.
Apparently, Chrysler saw a problem with the later geometry and fixed it with a taller spindle. Why? It sure wasn't because of the isoclamp setup. In fact I would be curious to know the distance between an A body's UCA and LCA inner pivots vs. the F body UCA and LCA inner pivots. If they are the same, or the F body's is less than the A body's, that pretty much blows the "no tall spindle" argument out of the water. If the F body's is taller, well that might not prove anything. I don't know these specs, maybe if I can find my FSM's I can dig that up.
You must remember the first A body came out in 1959, with the 1960 (model year) Valiant, and as far as I know the critical dimensions are the same till the end in 1976. The F body came out in 1975 (1976 model year), which means that the F body should have had at least 16 years more suspension design theory and experience (including the domination of NASCAR in the 60's) than the A body. Assuming similar lead times in design and development of the two new vehicle lines. Granted the Transverse Torsion bar isn't perfect, but it did have the benefit of a lot more experience than the A body suspension did. And CC liked it enough to convert all their RWD platforms to it eventually. Apparently the engineers who quit over it went to work in another industry because I'd take a transverse T bar car over any other domestic front suspension of the same model year, excepting high dollar sports cars of course. In fact I'd say the MacPherson strut design is a step back, but that is fodder for another thread.
The anti-tall spindle arguments are filled with a lot of mistaken assumptions and that makes me wonder about the validity of the argument.
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Re: Tall vs. Short Spindles
[Re: origcharger]
#17906
11/06/05 11:24 PM
11/06/05 11:24 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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That wouldn't have changed the vertical spacing between the two inner pivots. It is more likely the sheetmetal would be relocated/recontoured rather than the suspension components to make room. In fact, there is a big old access hole there to get to the inner pivot for alignment purposes so I don't think that theory holds water.
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Re: Tall vs. Short Spindles
#17907
11/07/05 02:00 AM
11/07/05 02:00 AM
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Joined: Sep 2003
Posts: 1,688
Marlboro, NY, USA
Rick_Ehrenberg
top fuel
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top fuel
Joined: Sep 2003
Posts: 1,688
Marlboro, NY, USA
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There were actually no less than THREE new knuckles being designed for '73-up A, B, E, F, etc cars. ALL of those used the identical spindle design (for the unicast rotors). All that differed was the height of the knuckle's upper section and disc adapter vs. drum support mounting. It sure stands to reason that they'd want to commonize at that point if possible. Forging dies were expensive - still are!
As far as designing for the "common man", it was mentioned or implied repeatedly in earlier posts that the only one who would use the full suspension travel was exactly that person! How is a tripling of bumpsteer for Joe Average an "improvement", pray tell? A diver who sucks would surely be more freaked out (and likely to lose control) by excessive bumpsteer, it would seem to me.
Just because something works for 98% of the people who use it doesn't mean it's a good design, e.g., all those Ford Exploders you see still greasy side down, Crown Vics w/o the fuel tank ruptured, etc.
I still have not seen one post with anything approaching a logical explanation why the typical Mopar guy, who just wants to do a disc brake swap as safely and cheaply as possible, should screw up his suspension geometry.
Rick
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Re: Tall vs. Short Spindles
#17908
11/07/05 02:30 AM
11/07/05 02:30 AM
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Joined: Jan 2003
Posts: 27,485
So Cal
autoxcuda
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,485
So Cal
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Quote:
You must remember the first A body came out in 1959, with the 1960 (model year) Valiant, and as far as I know the critical dimensions are the same till the end in 1976.
The 67-76 A-bodies have wider tracks. At least one of inner pickup point are moved out. Since the 60-66 cars use the same LCA's. Probably both.
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The F body came out in 1975 (1976 model year), which means that the F body should have had at least 16 years more suspension design theory and experience (including the domination of NASCAR in the 60's) than the A body. Assuming similar lead times in design and development of the two new vehicle lines. Granted the Transverse Torsion bar isn't perfect, but it did have the benefit of a lot more experience than the A body suspension did. And CC liked it enough to convert all their RWD platforms to it eventually. Apparently the engineers who quit over it went to work in another industry because I'd take a transverse T bar car over any other domestic front suspension of the same model year, excepting high dollar sports cars of course. In fact I'd say the MacPherson strut design is a step back, but that is fodder for another thread.
The anti-tall spindle arguments are filled with a lot of mistaken assumptions and that makes me wonder about the validity of the argument.
Playing arm chair quarterback trying to guess why CC engineers made each minute suspension change is pretty impossible IMHO. I bet if you interviewed everyone in the team that designed it you would get some conflicting answers even. And there has to be literally volumes of reasons.
I think this "verses" part of the discussion is played.
So....
looking at the second set of pics of Fatman spindles they look a little skimpy to me. Is it just me??
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Re: Tall vs. Short Spindles
[Re: Clair_Davis]
#17909
11/07/05 08:45 AM
11/07/05 08:45 AM
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Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
patrick
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
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Quote:
Why not LOWER the UCA mounting points to match the dimensions of the pre-iso-K cars and keep the A-body spindle?
RE: AndyF's spindle, using stock UCA's, I don't think I can tolerate a spindle that's much taller with the 5.7" BS wheels I've got. If it's possible to go significantly taller and not reduce my wheel/tire options, it would be worth it, even if it meant having to go with aftermarket UCA's. If that's not the case, I'll keep wider rubber up front and stick with the OEM spindles...
Here's another vote for the Tech Archives!
Clair
my 5th ave has the taller spindles (and yes, the horrible, death-inducing, nasty geometry bent t-bars...funny, how I can out handle most cars on the road with it), and I have about 1/2" clearance to the UBJ with 17x8 mustang wheels running a 3/4" spacer, FWIW....
1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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Re: Tall vs. Short Spindles
[Re: Rick_Ehrenberg]
#17910
11/07/05 11:30 AM
11/07/05 11:30 AM
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Joined: Feb 2003
Posts: 1,095
Bloomington, Illernoise
cptn60
super stock
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super stock
Joined: Feb 2003
Posts: 1,095
Bloomington, Illernoise
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Quote:
I still have not seen one post with anything approaching a logical explanation why the typical Mopar guy, who just wants to do a disc brake swap as safely and cheaply as possible, should screw up his suspension geometry.
Rick
You just wrote it yourself. All about the $s. And it isn't an unsafe swap, it's been done for years on A,B,C and E bodies for literally pennies of what a "proper" swap cost. I DO agree that with the availabilty of a repop forged knuckle, it's no longer viable. As far as the bumpsteer, in the swaps I've done; the tie rod pickup point was on the LBJ not the upright. No problem found, but I slow down for the turns, anyway. 
This space available for rent
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Re: Tall vs. Short Spindles
[Re: cptn60]
#17911
11/07/05 12:43 PM
11/07/05 12:43 PM
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Joined: Feb 2003
Posts: 4,204
Fort Worth, TX
Clair_Davis
master
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master
Joined: Feb 2003
Posts: 4,204
Fort Worth, TX
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Probably hasn't been done on C's, most C-body spindles I know of are about 2" taller than an A-body spindle (I had both sitting around). Talk about making a BIG change in spindle height... Plus, the "upgrade" ABE rotors are smaller DIA than the Budd rotors on the early C's and thinner than the unicast rotors on the later C's... not much benefit to be had from that kind of swap. That said, I was recently part of a conversation with a guy who was doing just that, FJM spindles on his 68 C-body. He was in Finland, IIRC, and there wasn't much else to choose from. I think I'd keep the drums in that situation.
Clair
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