Lowering steering rack and the effects of doing so

[SpartanZ32]

Hi, ladies and gents...I'm a total newbie to this forum, and not even an engineer. However, I am quite the "tinkerer", and love designing and bulding new things.

So with that being said, I am currently working on a 1990 Nissan 300zx....doing an engine swap (V8). The issue I'm having is that the steering rack is mounted a little too high on the front crossmemer, and it is taking up the space where the oil pan needs to be. I have no problem lowering the rack the 2.5"-3", but my concern is bumpsteer.

Will lowering the rack yield negative results (ie: bumpsteer, etc)? One thing that crossed my mind is that if I lower the rack 2.5", can I "correct" this by adding a 2.5" spacer to the tie rod end where it meets the knuckle? In my head, this will keep the same geometry as factory. Am I right or wrong?

I know this might be hard to answer from just reading my post. I can provide pictures if necessary.

Thanks in advance!!!! Any help will be gratly appreciated.

 

[patprimmer]

I think Archemedies gave a clue to the potential of the problem with his statement that went something like, give me a lever long enough and a fulcrum on which to rest it and I could move the world.

A few dents in the firewall and transmission tunnel that will be covered by carpet will be much closer to original that the exterior of your car after the first incident when that device breaks off level with the bottom of the original tie rod end mount on the spindle.

To do it right move the motor back and up if necessary, even if you just tilt the front up a bit to clear the rack after notching the sump.

You can also often get extra bonnet clearance by modifying inlet tracts, modifying under bonnet cross braces, very slightly springing or bowing the bonnet and maybe setting the bonnet slightly higher than original so it is hardly noticable. A 1/8" here and a 1/4" there where more visable and 1/2" here and 3/4" there where covered with carpet and maybe a flange or two ground back can add up to s serious missfit fixed.

Regards
Pat
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[MReilly]

How are your track rod ends attached to your steering knuckles?

Ball joints up or down?

If the ball joint is at the top you could possibly taper ream the knuckle from the bottom and refit the tre with the ball joint down, maybe swapping left to right and right to left if need be?

Then drop the rack the same amount as the difference in ball joint centre height (or a slightly different amount if you know your stuff).

Would give you a bit of extra room, not entirely sure on the stress implications on the knuckle though?