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Discussion Starter #1
Hi

I installed a Rod and Custom mustang II front end on a 65 mustang. The next person that worked on it moved the rack forward about 4 inches.
The control rods from the rack are now at a + or - 30 deg angle pointed aft. Is this a dangerous situation?
When I installed it, the rods were nice and straight like a OEM installation.

Thanks for any info.

Tom
 

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It will have slightly less turning ability because the distance was effectively shortened. As long as they dont go into bind at full lock at one side or the other, it should be fine.
But always check to be sure. Why did the other guy mess with it??
 

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While the Ackerman geometry effect could be less (or non existent ) with a rack mounted too far forward the spindle centerline, the possibility of a bump-steer problem could be a bigger/more important headache if it's a drag car. KY is correct that mounting the rack at the needed/required height is important to help reduce/eliminate unwanted toe change (bump-steer) during front suspension travel. But hanging a rack way too far forward the spindle C/L can also be another cause of some bump-steer.

This is because if the rack's outer tie-rod arms are rotated back (aft) at too great an angle the arms are now rotating in an arc that is operating in a much different plane than the suspension's control arm(s) are. Even if the rack is mounted at the correct height, if it's too far forward it could cause a sudden and increasing "toe in" change as the suspension travel approaches either end of it's total travel. If this happens (or not) kinda depends on a combination of how far forward the rack is mounted & how long/short the outer tie-rod arm's center-to-center length ends up being. A rack mounted too far forward can also cause binding/bending/failure at the ball socket joint (inside the rack boot) where the tie-rod is attached to the rack main body.

A rack mounted too far forward might cause a problem, or it might not. The only way to know for sure is to map-out the front suspension's total travel and check for amount of Ackerman geometry effect, and to see if it does/doesn't have any dreaded bump-steer.
 

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Discussion Starter #6
Thanks Guys

I will send this email to the owner. I do not want to be responsible for anything that may happen because of the changes.

The reason they moved it forward is because they felt the engine should be back farther and lower..

In my opinion, it just doesn't look safe.

Thanks
 
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