74 pinto crossmember question.

Hello, I have a question about stock 74 and up pinto crossmember. I narrowed mine 7 1/2" and when I put it back together, using some of what I cut off inside half ways into one end, so I could be sure everything was lined up and level. I also have a 3 hole rack that is narrowed the same amount and all 3 bolts fit good when I put it all together, the top hats aren't flat where the slotted holes are, but are angled downwards 5 degrees and the shock tower are at 15 degrees. My question is, is going to be a problem to align the front end? I'm also using 1" narrowed a arms too. Thanks.

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Originally Posted by 48thames

Hello, I have a question about stock 74 and up pinto crossmember. I narrowed mine 7 1/2" and when I put it back together, using some of what I cut off inside half ways into one end, so I could be sure everything was lined up and level. I also have a 3 hole rack that is narrowed the same amount and all 3 bolts fit good when I put it all together, the top hats aren't flat where the slotted holes are, but are angled downwards 5 degrees and the shock tower are at 15 degrees. My question is, is going to be a problem to align the front end? I'm also using 1" narrowed a arms too. Thanks.

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You've thrown all the factory geometry out the window, so I wouldn't think any of the published figures would apply anymore. You'll probably just have to try different settings until you arrive at an agreeable set of values. I might begin at 2 degrees positive caster, 1/2 degree negative camber and 1/16" of toe-in and see how the vehicle drives and how the steering wheel returns to zero after a turn. If you need more return, use more positive caster.


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Thanks for the info. I have searched the internet everywhere and I can't find out if the top hat slots came factory angled in, or leveled. I was hoping someone had installed one and might know. Other then the narrowed a arms, I think because e everything is narrowed the same amount, it should be close to factory settings. I could be wrong. Thanks again.

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Originally Posted by 48thames

Thanks for the info. I have searched the internet everywhere and I can't find out if the top hat slots came factory angled in, or leveled. I was hoping someone had installed one and might know. Other then the narrowed a arms, I think because e everything is narrowed the same amount, it should be close to factory settings. I could be wrong. Thanks again.

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Looking at the suspension from the front, the upper arms were relatively flat. In my experience, handling can be improved by raising the arm at the outer (balljoint) end of the arm. This will allow some camber gain on bump and will allow the tread of the outside tire to remain on the pavement in a turn, rather than rolling over onto the sidewall of the tire. I have seen spacers which are commercially available to space the arm up. I designed an IFS from scratch with help from author Carroll Smith, in his book Tune To Win, and used an angle of about 10 degrees up (been a while ago and I have forgotten the exact angle). This allowed the suspension to gain 3 degrees negative camber on bump to help keep the tread flat on the outside tire in a turn.

It seems that I remember the upper control arm on the Pinto was installed at about a 5 degree angle downhill to the rear as the control arm is viewed from the side.

If you'll get the book Tune To Win, Mr. Smith explains in the back of the book how to make what he calls "paper dolls", using heavy construction paper and stick pins to make a workable scale model of the proposed suspension so you can see how everything is going to work. I VERY strongly recommend that you follow suit.


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The angle that your talking about on those upper arms is the brake anti-dive---I think Heidt's cataloque or web site covers it

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Originally Posted by jerry clayton

The angle that your talking about on those upper arms is the brake anti-dive---I think Heidt's cataloque or web site covers it

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Thanks Jerry, I did know that at one time, but my brain won't work like it used to.


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Thanks guy's, but it's not the anti-dive that I am worried about, because it's built in from the factory. The angle that I am worried about is if you were standing on side of car facing the top hat and tilted it downwards 5 degrees towards inside the frame, with the anti-dive still angled to the rear. I think that I am trying to say, if the a arm is adjusted all the way forward in the slots, as you slide it backup the adjusting slots, I think it will raise the a arm 5 degrees. I am sorry about the confusion. Just trying to find out if the factory built it in that way or I have something not right when I narrowed it.

get a Heidt's cataloque---they had it pretty well done up in there a few years ago