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"I'll post my rebuttal later." Jeez, and I thought you had once said you wouldn't comment on this issue again.

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Eh, I got a second wind. I have no problems with the taller spindles provided:

A)The person is completely informed of the difference and is cautioned as to the possible outcome of using the taller pieces before making a decision.
OR
B)The person uses the tubular upper control arms to correct the problem.

Here's the way I look at it. Why take the chance? Maybe 1 out of 1500 have problems with the taller spindles. But you know what, the way my luck is, I'd probably be that 1. This is the safety of you, the safety of your passengers, and the safety of me, John Q. Motorist, who's in the on-coming lane. They now make upper arms to match the taller spindles, so it's a no-brainer. Mopar Action has always advised against using the taller pieces. Mopar Muscle, on the other hand, can't make up their mind. Some articles promote them, some articles say to avoid them. The MM loyal here will even be so ridiculous as to state that 'those articles against taller spindles are just reprints or from outside sources.' Glad to know that MM takes my safety so seriously. This has been a HOT topic for a long, long time and there has been some personal/professional debate between eberg and dulcich, so you would think that MM would at least take the time to read their own dang articles to have some degree of consistency. Anybody can take material from outside sources and reprint it verbatim without checking it. It ain't too responsible to do so, though.

The tubular arms have a slight angle to the upper ball joints to keep them from being over-stressed by the taller knuckles on pre-73 cars.
Here is why you need them:


For basic info about the swap, go to http://moparaction.com/Tech/archive/disc-main.html

Recent opinion posted here by Eberg of Mopar Action fame:

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On the steering knuckle "great debate":

(Here we go again!) Yes, the taller knuckles may give some small camber-gain improvement. But, IMHO, the tripling of bump steer (full travel) makes the swap a no-brainer: in a word, don't.

I've been doing lots of research into the original suspension design parameters of these cars. Incredibly complex, these guys (Highland Park engineers) actually had four seperate computer programs to analyze the angles and geometry. It seriously maxed out the (computer) hardware of the day - this was ~1960 were talkin'!

I've had at-length discussions with 4 of these guys (unfortunately 2 are now lookin' at the wrong side of the grass) and ALL thought the tall knuckle was a real bad idea.

The left-to-right flip (re: swaybar clearance) is another scary deal. If you take GREAT care to assure that the brake hose is properly routed and has enough length and friction protection for full lock / full-travel safety, then, sure. But I've seen too many - VERY many - cars where the hose acts as the rebound bumper! Please be careful! Rager proably had a point when he didn't wanna open this can of worms. The stuff I've done has always had either 100% factory engineering or contained caveats up the yazoo!

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Guys will probably mention the MM article concerning this, here are my thoughts:
Here are the numbers from the MM compairison article. To start off, the front clip used was set not at stock height and rake, but 1 inch lower than stock height and at a rake of 1.5 inches. The reasoning was that 'most cars of today have a slightly raised rear' and the lower height was 'also quite common.' Ok, fine, you want to do a test that reflects common changes to mopar suspension, but to do this without the addition of a base test at stock height does nothing but leave doubts and conjecture. In my opinion, this test was fatally flawed by not doing a 'base test.'

But anyway, you can see the numbers below. The Toe change was excessive during extension, and this was dismissed by saying 'How often is your suspension fully extended on Main Street?' Sure, laugh and chuckle about the mental image of your roadrunner running through town a'la Bullitt, but what if it is? That's like saying you really don't need car insurance cause you don't plan on having accidents. It's a small point, but a point that carries throughout the test and the article. This was distrubing to me, especially since a 'full engineering study' was not conducted where some of these problems may become more pronounced.

The big red flag was the change in roll center. I'm sure you've seen the 'imaginary line' drawings that diminish into the pavement to illustrate this in the past, and you've probably understood it better as 'low center of gravity.' The greater the number, the less stable the car will be. If you look at the numbers below, you can see that the recommended A-body spindle had a range of 5.366 to 6.849, and the b-body piece 6.678 to 8.677. Woah, did I read that right? Yes, you did. The maximum on the 'recommended' spindle is dang near the minimum of the later B piece.

Another point of argument on these was that the ball joints would be over-angled and could fail. Supposedly a test was done by dulcich on various ball joints, and it was found that while newer joints are within thier intended range, factory or NOS pieces were not and risked failure.

Brought up by Ebooger was the fact that the A/E spindle was used by chrysler up to 76, well past the intro of the B piece in 73. If these spindles were ok to interchange, why not install them on everything and lower production costs and assembly line confusion?

To further this mystery along, MM continues to not be able to make up their mind, as I mentioned earlier. One article says they're safe, another says they aren't, and yet another recommends the use of the corrective tubular arms when used with the taller examples.If they're so great, why expensive new upper arms?

Bottom line here is that the late spindles probably can be (and have been) installed without a major catastrophe, but they are not a 'bolt-on replacement part.' The use of them will effect how your car handles, and everyone should read what's available on them before deciding one way or another. For me, the solution is simple. Either use the correct spindles, or buy the corrective upper arms.


Last but not least,

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I have no official training in the subject, just what I've read over the years, and I've never made it out to seem any different. I just feel that to throw these taller spindles out there as a bolt-on is incorrect in the least, and downright dangerous at the most. People have a right to hear both sides of the argument. As far as those I've quoted, Eberg is a S.A.E., and if you want to boast real-world experience, one has to look no farther than his exploits of the 'green brick.' Since I don't have the capability to do a 'full engineering study' on the taller spindles, I have to go by what information is out there. And I have yet to see enough to convince me that the swap is a safe bet bar-none.

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