89_RS

http://www.flamingriver.com/index.ph.../s0005/FR40022

The idea has been bouncing around in my head for a while, but barring seeing a rack with the proper throw, it was a nice idea. I seem to recall that the proper throw is around 6" (https://www.thirdgen.org/forums/susp...ck-pinion.html) Now it seems to be closer to reality. Flaming River is offering a rack that is dimensionally interchangable with the Mustang rack with throw over 6". No mention on lock to lock turning.

http://www.detroitspeed.com/products...ring-rack.html

DSE is also offering a rack with a 5.5" throw & 3 turns lock to lock.

Were getting close to that coveted power setup

89_RS

Figured I'd bump this with some more data. After looking at the DSE rack specs, it sounded very familiar to the Pinto rack setup and with some digging found that the DSE rack has a .25" more throw than a pinto. Sounds like its a prime candidate for Racecrafts R&P spindles.

All thats needed is a new shaft setup. Some digging should yield the necessary parts.

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iTrader: (14)

you dont need the 5" and longer travel rack setup with the short arm style racecraft spindles fyi.

scooter

iTrader: (11)

Custom Racks really are not that expensive, get built what you want. Flaming River isnt the end all of steering stuff, mostly just some main line crap they try to push when there is better stuff out there

89_RS

As far as I understand it, the Pinto manual rack has a 5.25" throw which is why Racecraft made a modified spindle for it so you could maintain stock turning radius. A power rack with nearly the same throw & the modified spindles would seem to allow you to do AX with them as you would have at least the same turning radius.

scooter, I had not known about these people before. It would definitely be worth it as the stock spindles work just fine already.

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iTrader: (14)

not trying to argue here, but i have more


hypothetically, if the stock system has 5.25" of travel, and the rack has 5.25" of travel, the turning radius would be the same, without modifying the steering arm on the spindle. Once you shorten the arm, you are changing the steering ratio, and now the spindle will turn more with less input from the rack/steeringbox. So now, with a shorter arm, you dont need as much travel from the rack.

And the more i see/read from people who actually have racecrafts spindles, the less interested i am in them.

?

89_RS

I completely agree. Only reason I'm thinking of the spindles is that in the thread I linked above, several people came to the conclusion/agreed that the stock steering system has around 6" of throw. Seeing as how the stock steering has more throw than most racks, a shortened steering arm is required to make up for the lost throw. A shorter throw plus stock length arms means a worse turning radius.

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iTrader: (14)

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iTrader: (14)

now what if you use the short steering arm spindles, with a stock steering box? super fast steering! 1.5 trns lock to lock? maybe better. im sure the steering would get a bit heavier.

89_RS

Conventional logic would seem to make that work. But I worry that the stock system had the steering stops integrated into the locks on the steering box and not a physical stop on the spindle or A-Arm.

scooter

iTrader: (11)

The box does have a stop built in but those would be useless in that case. The shorter arm would multiply the motion of the throw and cause the wheel to hit something before it would hit the internal stops.

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iTrader: (14)

stock cars have a stop on the a-arm, with a tab on the spindle. so the stops would still function.

Im pretty sure steering input would be stiffer, but not positive.

Also this would drastically change the angles of the steering linkage, and that may affect bump steer?

dead sailor

The problem with racecraft's r&p spindles is that the tie rod will hit the tire/rim unless you are running skinnies up front. I ran into this problem when ordering a pinto rack setup with a road race k member. They actually called me and told that it would not work if i planned on running any rim wider than like 4 or 5 inches.
However I'm still looking to run a rack and pinion setup. I have to call this company unisteer, they make custom racks.

89_RS

I'm beginning to think the saying "If it aint broke, don't fix it." is appropriate here. Once one technical hurdle is overcome, 3 new ones show up

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iTrader: (14)

funny how that works

fast377

iTrader: (4)

The only rack with a close amount of travel, is a mid 90s thunderbird. It's about a half inch less than our car oem (if I remember right...it's been a while)

You can't add travel to a rack. What it has is what it has. When I did my conversion, I called unisteer and that's what they told me. And that flaming river rack posted above is expensive. You're better off getting a custom k member built like I did.

Yes, this is why the Racecraft spindles are necessary.

This is true depending on your wheel diameter. If you have 18s, then you just have to clearance the tie rod ever so slightly. I you have 19s or larger, then you are fine. I have 19s now, and have no issues. Plus you would want to get a bumpsteer kit anyways, so if you just drill the spindle to use a 5/8 bolt instead of the tapered thing you might be able to fit a smaller wheel.

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iTrader: (14)

are you talking about stock spindles here or racecrafts? stock spindle tie rod ends will clear a 18" wheel, racecrafts will not, and add a bump ster kit to racecrafts, and forget about it unless you are using 22's.

these are 17" wheels and racecrafts spindles, and from this pic, there is no chance a 18 will work, unless im missing something??, and even more so with a bump kit. i guess a 19 could work, apparently does if you have this setup


for that matter, you shouldnt need a bump steer kit with drop spindles, since the steering geometry stays the same, and the wheels move up. if anything, unless the car is sitting on the ground, the tie rod may want to move up some.

or do you have the arms with the shorter steering arm? in that case you are probably more correct, i believe this pic is the stock length arms.

now that i re-read your post, it seems that is the case, so my blabbering can be ignored for the most part

scooter

iTrader: (11)

I didnt say you could ADD travel to a rack, get a CUSTOM built rack with the travel you want. I rememember reading on the custom build sheet for the Unisteer that you put how much travel you need, unfortunately the build sheet link returns a 404 so I cant show it.

fast377

iTrader: (4)

18 and 19 inch wheels will work with shortened steering arm racecraft drop spindles...I've had both on my car. It's a very close fit with oe type tie rods (I actually had to clearance mine with the 18s).

You're right about the bump steer kit probably not being needed...but I have one anyway. It won't work using the supplied tapered fitting. You have to drill the spindle arm out for a 5/8" bolt and use that. That gives you all the room you need around the wheel.

For those interested, here is my setup:

Custom made tubular k-member (made by PA Racing to accept a fox mustang style rack)
1997 Thunderbird rack
Racecraft drop spindles w/short steering arm
Baer brakes bump steer kit (for an early 4th gen because the threads match the thunderbird inner tie rods)
19x8 front wheels with a 275 tire (was a 18x8 with a 265 tire)

fast377

iTrader: (4)

Sorry...I was thinking of having a stock rack modified when I read your post. Unisteer can widen and shorten them. That is the case where you can't add travel.

dead sailor

Does anyone know the center to center distance on the t bird rack?

fast377

iTrader: (4)

Center to center of what? Mounting lugs or inner tie rod sockets? Mounting lugs is 15.5 I believe...but they are off center in relation to the rack.

dead sailor

The inner tie rod sockets

FlyDoc

so If I'm reading this correctly,
you are running the Racecraft drop spindles for the rack & pinon shortened steering arms and they are clearing somthing other than skinnies
like the RaceCraft tec told me????

fast377

iTrader: (4)

Correct. My current front wheels are 19x8 with a 275/35/19 tire.

fast377

iTrader: (4)

Note: The bolt in this pic is NOT the bolt that holds my stuff together. It is for illustration purposes only. I'm waiting for my proper bolts to arrive. I had to get everything together and measure what length I needed before I ordered.

Andrew91GT

Did anything ever happen with this?

I'm interested in a stock or stockish steering geometry rack and pinion, prefer manual but it is what it is.....

There are two issues that I am aware of, one has already been touched on which is the throw... the other which has kind of been mentioned is the distance between tie rod end pivot points which will affect bumpsteer and such. If this distance is not right, you can minimize bumpsteer but not eliminate it with a bumpsteer kit.

Andrew91GT

The unisteer custom rack order form seems to work..... of course this is the one for manual steering.

http://unisteer.com/seach_by_vehicle...nd_pinion.html

Andrew91GT

Here is the custom power rack form:

http://unisteer.com/doc/61/raw.html

fast377

iTrader: (4)

I have a working setup. Throw is perfect (although I am using Racecraft dropped spindles with the short steering arm). Now concerning tie rod pivots...I don't have exact measurements. But the inner pivot is within a half inch of the control arm pivot and I am running a bump steer kit. I have not had a chance to measure my bumpsteer, but my alignment went over without a hitch. I have only driven the car around a small parking lot, so I don't know how it all feels...although my first impression is very good. Once I get some other issues sorted out, I'll give it a nice flogging and see what happens.

iroczracer07

iTrader: (2)

Hey fast377, did you ever get to take your car out for that flogging? I'm curious as to how it all worked out and if you've got some more pics of your set up that show how it looks on the car at ride height. That was pretty niffty how you figured out the 97 thunderbird rack would work. I'm thinking about copying you as a matter of fact

fast377

iTrader: (4)

I've driven the car around the neighborhood, but that's about it. Between moving, and other things going on I haven't had much time to finish working out all the little bugs. Around the neighborhood, with a max speed of about 40, it drives great. Steering is tight, responsive, and smooth. No bumpsteer that I have noticed yet. All in all, I would say it turned out great.

evo-offer

just curious, but wich steering shaft and rack did you use?

hellz_wings

iTrader: (2)

fast377: This looks like quite an involved mod. Have you driven the car since? I have been contemplating using a R&P ever since my Lee 670 box got loose on me again. If my over the winter replacement of this box (sending it to Lee and then we will see in the spring if it holds this time around) doesn't work I'll most likely be going to a R&P setup. The 12:7 to 1 ratio is fine for me I just cannot stand the off center feel of a loose steering box. Thnx

blakecharles

wait... so the 1997 thunderbird power rack with a custom PA racking K-member and racecraft drop spindles worked out??? what about with stock spindles (my wheels are too wide for drops)??

Anyone know if Appleton still makes a power rack for our cars???

FlyDoc

I have the drop short arm spindles with a Z quick ration box, it gives me about 1.75 lock to lock, I like the feel and feed back. it took a little while to be able to drive a strait line on the highway. with out the car running it is all I can do to turn the wheels! so to turn, it's start it, or jack the front up.

I'm using Spohn A-arms, they had stop pads on them, but nothing on the spindles, so I had to fabricate some.

89ROC-Z

iTrader: (7)

Any update on this? I want to ditch the big *** box and go rack and pinion

cam406406

iTrader: (1)

Ya don't run those spindles on a street car they won't last. And are a saftey issue

FlyDoc

I don't think that using RaceCraft spindles are any more of a safety issue than those that are modifying a OEM spindles.
I have been using RC 2" drop, short arm spindles for more than 3 years as my daily driver and SCCA on the weekends with no issues. when the spindle failure thread started I was concerned and have been following it.
At that point I went to the Army Brigade that I was in prior to my medical retirement and found an old friend that I had them do a NDI (Non Destructive Inspection) on the welds and all of the welds were good. I think you could do magnaflux to them after removing the powder coating. which probably be a good thing to do regularly, depending on type of use.

hellz_wings

iTrader: (2)

I don't understand why they wouldn't just build them to be street able.. add more material or whatever.

cam406406

iTrader: (1)

I called them
Direct from them it's not the welds to worry about it's the small 7/16 boil holding it all together. It's a non taper bolt small bolt

Roc89

Hey I know this is an old thread but I was wondering how your R&P conversion turned out. I have an 89 Iroc and I am planning to do the same conversion but wanted to get some input from people have already done it. Would you be able to give me some advice. Thanks in advance!

Tombowman89

Ok I’m considering doing this mod, if you get a chance please contact me by email. I’d like to get some more details from someone who’s actually accomplished this without a bunch of biased opinions from the forum. I have some hurdles with my build and I need some specific details I need answers to. My email is tombowman89@gmail.com