Anyone autox a Gen 1/2 with a Gen III rack?

[zak]

Have actually purchased a low mile used Gen 3 ZF rack and am considering swapping it in (I am aware of the need for a custom pressure hose, and the desirability of a Gen III lower steering link).

My question is, has anyone autocrossed a Gen 2 (or Gen 1) with the Gen 3 rack? Stripped or street trim?

My concerns are:
1.) Rack ratio - Gen 1/2 is 2.52, the Gen 3 is 2.7, therefore a slower steering ratio.

2.) Paul posted a while back a comparison of the Gen 2 and Gen 3 pumps. Most specifications (min, max pressure etc.) were the same or close, but the volume of the pump on the Gen 3 was double that of the Gen 2. On my old Fox chassis Ford I once had the steering lock solid during a rapid steering input after swapping to underdrive pullies - my understnading is that it was caused by a pump volume constraint.

Any experience appreciated, don't want to regret this. zak

 

[St Louis SHO]

My car has a ZF rack in it, nobody who drove it at NHMS complained. They actually called me shortly afterwards and asked to have a SF/rack swap...

 

[Racer X]

John, with an MTX the chances of Throttle Lift Understeer are pretty slim (as long as you don't attempt super aggressive steering inputs at idle...).

 

[zak]

Thanks for the feedback folks. The issue with autocross is that you are often making very rapid steering inputs/corrections/changes compared to track driving. Thus the loads on the power steering system are much higher. I guess parking lot steering is a good example, except that you have to picture 70 turns/direction changes in under 2 minutes.

The other issue is with the higher ratio you end up going hand over hand more often (to be avoided in autox).

Anyone else have autox experience with this rack?

And when is NESHO going to come out with the pressure hose?:wave:

 

[SHOspazz92]

I'll let you know how it is when I get back. Between the Gen III Subframe, ZF Rack and 275's up front, I expect it to be a completely different feeling car.

-Sam

 

[zak]

Thanks Sam - if you feel any moments of steering wheel lock up/momentarily getting hard to turn (other than when those giant tires kiss the fenders ;-) ) that would be useful information.

What did you end up with for wheel offset?

 

[SHOspazz92]

Thanks Sam - if you feel any moments of steering wheel lock up/momentarily getting hard to turn (other than when those giant tires kiss the fenders ;-) ) that would be useful information.

What did you end up with for wheel offset?

23mm Offset. I don't think I'll have an Issue with the fenders touching the tires (Keep in mind, Im still only running 245's out back), My suspension just doesnt give that Much.

-Sam

 

[zak]

Pretty massive change in scrub radius there, this should be the ultimate torture test for the Gen III rack.:thankyou:

Make sure your power steering cooler is clean. They tend to get greasy from slight hose leaks and then attrack dirt, which reduces ability to cool.

I detached mine from the mount, but left the hoses on, and dipped it in carb cleaner a couple of times.

I assume you are running an underdrive PS pully? Stock crank pully?

 

[K-Dawg]

And when is NESHO going to come out with the pressure hose?:wave:

I had one made for about $11.

 

[SHOspazz92]

Pretty massive change in scrub radius there, this should be the ultimate torture test for the Gen III rack.:thankyou:

Make sure your power steering cooler is clean. They tend to get greasy from slight hose leaks and then attrack dirt, which reduces ability to cool.

I detached mine from the mount, but left the hoses on, and dipped it in carb cleaner a couple of times.

I assume you are running an underdrive PS pully? Stock crank pully?

Stock Pulley and Stock Cooler. I'm not to worried about it.

Thanks for the Tip Tho!

:sun:

-Sam

 

[ForcedSHO]

Would love a DIY on this.

 

[pitaSHO]

If you want really tight steering just change your caster. My 91 came with an insane alignment and it would change lanes if I sneezed. Very touchy. I ended up changing it back to a stock alignment because I do more road course than auto-x and didn't really like how touchy the steering was.

Just an idea.

Chris K.

 

[zak]

Sam have you been out yet?

 

[SHOspazz92]

Sam have you been out yet?

No, I'm still Deployed to the Middle east. I get back in June. My car has been at Kirk's since January and I have not gotten any word if it's even been started on yet.

-Sam