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Old 03-30-2009, 09:40 AM
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Default Citation Rack and Pinion for a C3?

There is a reference to a Citation rack install in the Speedway catalog, they offer a conversion U-joint for this conversion. I looked the rack up and it is a end take off rack. Has anyone tried this rack in a vette? It looks like an end take off rack might be a better fit for our vettes. Not sure if the ends would be the correct length. May try and find one local to measure.

Neal
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Old 03-30-2009, 09:45 AM
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Originally Posted by 496BBC View Post
There is a reference to a Citation rack install in the Speedway catalog, they offer a conversion U-joint for this conversion. I looked the rack up and it is a end take off rack. Has anyone tried this rack in a vette? It looks like an end take off rack might be a better fit for our vettes. Not sure if the ends would be the correct length. May try and find one local to measure.

Neal
For the stock a arm geometry (long lower arms, cross shafts about 16" apart) you will need a very narrow end take off rack, the tie rod joints have to be in the right spot to get a proper bumpsteer geometry. Don't know the width of the citation rack but it's probably a lot wider than around 16". That's why I used the appleton rack, but it's front steer.
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Old 03-30-2009, 10:10 AM
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I agree with TT, as my junkyard and parts house shopping went crazy for some months trying to find a rack that was narrow enough, and still had power assist, and still tossed the tires ~6" in either direction....and was rear stear.....

I never found one, closest I could find was a Ford Taurus, and the tie rods would be abut 6-9" long...WAY in hell too short....

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Old 03-31-2009, 01:17 AM
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The Mustang II/Pinto PS rack is 42 inches end to end (I think a C3 is ~43 inches). I'm not sure if it's a rear steer.

I happen to see a Honda Civic rack that looks pretty compact and is a rear steer/center take off. Don't know what year it was from.
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Old 03-31-2009, 01:46 AM
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Well I finished the alignment today and was able to take a short drive. It definantley has a better feel, now I'm no track driver so this is just my opinion on regular everyday driving on public roads. Its more responsive to driver input and has little to no slack on center.

The one thing that bothers me a little is there is a small amount of deflection of the center bracket that bolts to the rack and connects the tie-rods together, when turning the wheel while the car is sitting still. I'm thinking of adding a guide to this center bracket that would bolt to the frame rails and allow the center bracket to slide on, this would reduce the deflection to almost nothing.

I'm curious if anyone else is seeing this deflection of the center bracket. It may just be a poorly rebuilt rack. If I grab the center bracket with my hand I can move it around some. It would be nice if I could find a diagram of a grandam rack to see what's inside. To try and see what may be moving around.

I still have to change the lower column BRG

Neal
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Old 03-31-2009, 01:49 AM
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After reading TT post I realize that he is exactly right, the rack would have to be about 15" long to use an end take off rack.

scrap that idea


Neal
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Old 03-31-2009, 02:12 AM
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Quote:
Originally Posted by 496BBC View Post
The one thing that bothers me a little is there is a small amount of deflection of the center bracket that bolts to the rack and connects the tie-rods together, when turning the wheel while the car is sitting still. I'm thinking of adding a guide to this center bracket that would bolt to the frame rails and allow the center bracket to slide on, this would reduce the deflection to almost nothing.
I saw this Grand Am rack on a Mustang(?) that was listed on Ebay. Looks like they did what you are saying, put the center bracket on a guide rod to stabilize it. That twist on the CTO point can't be good. I'm surprised it isn't the source of binding.



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Old 03-31-2009, 09:36 AM
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Quote:
Originally Posted by 496BBC View Post
The one thing that bothers me a little is there is a small amount of deflection of the center bracket that bolts to the rack and connects the tie-rods together, when turning the wheel while the car is sitting still. I'm thinking of adding a guide to this center bracket that would bolt to the frame rails and allow the center bracket to slide on, this would reduce the deflection to almost nothing.
I saw this Grand Am rack on a Mustang(?) that was listed on Ebay. Looks like they did what you are saying, put the center bracket on a guide rod to stabilize it. That twist on the CTO point can't be good. I'm surprised it isn't the source of binding.




That's what I'm talking about, maybe not that heavy but the same concept
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Old 03-31-2009, 12:18 PM
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THAT linear bearing concept is heavy as hell, and subject to extreme wear in a street environment....I also see it hanging up under heavy use..

THE one reason I never did any long legged center adaptor to my install was just that, I stuck one of the bolts in, clamped with vice grips in line, and twisted to see how much play in it, when doing the mock up...and the amount of necessary slop in there told me there was too much inherent twist to the slider, AND I was not putting any additional torque on it in any twisting mode via the tie rods....IMO, too much for the rack to handle.....

What that M/E I worked with....some comment I made about some aspect, he says 'Engineering first law, thou shalt NOT STRESS the Merchandise'.....I took that to heart in my install....
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Old 03-31-2009, 03:44 PM
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Quote:
Originally Posted by 496BBC View Post
I'm curious if anyone else is seeing this deflection of the center bracket. It may just be a poorly rebuilt rack. If I grab the center bracket with my hand I can move it around some. It would be nice if I could find a diagram of a grandam rack to see what's inside. To try and see what may be moving around.

I still have to change the lower column BRG

Neal
Mine too deflects a little when I try to go lock-to-lock when the car is stationary. I dont think I can move my center bracket by hand though. There definitely needs to be some kind of stabilizer like that mustang, although I personally dont feel comfortable having anything any lower than the rack, especially another steering component.
Maybe if you moved that stabilizer bar off the rack, and had it mounted behind the crossmember, between the two A-arm cross shafts. That would seem more compact and keep things from hanging low. only problem I see is that you might have to have those slides that ride on the bar too close together to do much.
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