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throttle
03-25-2008, 02:07 PM
Does anyone know a company that could build a steering rack based on my specs? I've contacted Saco and they said that they couldn't. I need one with really quick steering. I need 3" of rack movement with 3/8 turn of the wheel. *Lock to lock on the wheel will be 3/8 turn.

minibajaman
03-25-2008, 02:30 PM
I've looked some, and no such company exists that I have found. *There is a company called [url=http://www.unisteer.com/:3dnx7hn9]Unisteer[/url:3dnx7hn9] that will do custom racks, but last I checked the quickest ratio they have is approx 2 turns lock to lock for approx 4" of rack travel.

Can you make new steering control arms for the uprights? *Then you could use a not so quick rack but still get close to the lock to lock you need. *Although 3/8 turn lock to lock is really short and probably not possible with most currently available racks. *Is this for a Pilot?

yoshi
03-25-2008, 02:31 PM
Does anyone know a company that could build a steering rack based on my specs? I've contacted Saco and they said that they couldn't. I need one with really quick steering. I need 3" of rack movement with 3/8 turn of the wheel. *Lock to lock on the wheel will be 3/8 turn.move the control rod closer or farther away from the spindle and you'll get the same thing, only a boat load cheaper.......

throttle
03-25-2008, 03:24 PM
Yes, this is for a Pilot.

Yoshi - say again? Not sure I am following you. *This is a rear steering set up.

K-fab
03-25-2008, 03:32 PM
If you move the location of the tie rods on the spindles closer to the spindle (shorten the steering arm), it will quicken the steering. * It will also increase the amount of leverage needed to turn the wheels and make it harder to input steering.

But, since this is on a Pilot, with cast spindles, it's really not an option. *There's not enough meat to drill and machine flats for tie rod mounting changes.

You may want to contact Dan Roberto - he made (makes?) a killer little rack that may have the throw you need. *I had one in my old Moskito and the three Briggs cars have them. *They work very well.

LiveWire
03-25-2008, 04:02 PM
Shortening the tabs on the knuckles where the tie rods connect would quicken the steering using an off the shelf rack. However, it would increase the load on the tie rods so they would have to be beefier. Play in the tie rod ends would be amplified.

Some rough math: You need a pinion with an 8" circumference at the pitch diameter. 8/pi = 2.55. You would have to go with 2.5 or 2.625 if using 8 diametric pitch gears. The OD would be 2.75 if using the smaller one. If the rack was 3/4" thick and you have 1/2" for the top and bottom casing and clearance around gear you get 4", 2.5" from the centerline of the steering stem down. You would have to measure from the center of the steering stem down to see if you would have clearance. Where the rack ends up may cause bump steer issues.

The flag is welded to the steering stem on the Pilot. That would have to be cut off and possibly splined or an entire new shaft made.

LiveWire
03-25-2008, 04:03 PM
K-fab beat me to the submit.

dunerocket
03-25-2008, 04:32 PM
What about running a couple steering quickeners (I think that is what they are called) inline? *Might not get the exact result, 3/8, lock to lock isn't much. *Steering effort would be increased.

Bugpac
03-25-2008, 04:43 PM
I can get a super small rack, has about 3/8 to 1/2 turn lock to lock, my dealer page is down, but i was looking at it a while back, its about 350 bux tho...Let me know if you have interest and i will nail all the figures and specs down for you, the page should be back up later today...

minibajaman
03-25-2008, 04:56 PM
I can get a super small rack, has about 3/8 to 1/2 turn lock to lock, my dealer page is down, but i was looking at it a while back, its about 350 bux tho...Let me know if you have interest and i will nail all the figures and specs down for you, the page should be back up later today...

The Stiletto rack? *I didn't realize it was quite that quick. *The one that I have played with before was maybe 3/4 turn lock to lock. *Or if I'm completely wrong then providing some more info would be helpful...

Bugpac
03-25-2008, 05:52 PM
[quote="Bugpac\";p=\"66262":3k5xf3s0]I can get a super small rack, has about 3/8 to 1/2 turn lock to lock, my dealer page is down, but i was looking at it a while back, its about 350 bux tho...Let me know if you have interest and i will nail all the figures and specs down for you, the page should be back up later today...

The Stiletto rack? *I didn't realize it was quite that quick. *The one that I have played with before was maybe 3/4 turn lock to lock. *Or if I'm completely wrong then providing some more info would be helpful...[/quote:3k5xf3s0]

It may be just that, the site is still down, but i will post some info after it comes back up... [smilie=biggrin.gif]

stress
03-25-2008, 08:06 PM
C-moore offroad is building me a car with a pilot steering wheel and they putting a steering quickener on the car with 2 to 1 ratio before the shaft gets to the rack and pinion box , the steering wheel has a 70 degree turn angle from straight to full lock. *They are using the normal rack they use on the there other cars.

K-fab
03-25-2008, 08:27 PM
Just remember - any sort of quickening device or any modifications to the system that give you more wheel movement versus less steering input is going to increase the effort required to steer and the feedback will be amplified too. *More movement from less movement is going to require more work on the input.

Go back and look at your physics books - the steering system is nothing more than levers and motion ratios. *Even the steering rack is a modified lever. *Changing one aspect will change the entire mechanism.

Make sure you get a good steering damper on the system to help combat feedback. *A good jolt can rip a thumb right off if you have it inside the steering wheel's spokes.

Bugpac
03-25-2008, 08:36 PM
5.33:1 - 12" overall length, 295.00 bux tho...

Jay1823
03-25-2008, 11:40 PM
Just remember - any sort of quickening device or any modifications to the system that give you more wheel movement versus less steering input is going to increase the effort required to steer and the feedback will be amplified too. *More movement from less movement is going to require more work on the input.

Go back and look at your physics books - the steering system is nothing more than levers and motion ratios. *Even the steering rack is a modified lever. *Changing one aspect will change the entire mechanism.

Make sure you get a good steering damper on the system to help combat feedback. *A good jolt can rip a thumb right off if you have it inside the steering wheel's spokes.

Yeah i learned that the hard way, Bug was witness to that cluster f@$%

LiveWire
03-26-2008, 09:34 AM
The more pieces in the steering, the more play there will be as well.

Odyknuck
03-26-2008, 09:42 AM
If your interested I have a Howe 1.5:1 sterring increaser/reducer I will not be using.
Steve
216-695-0733