Z RATED IROC

Just wondering how many of you have converted to a Rack & Pinion.
Did you go Power OR non powered rack.
4th gen Rack, Pinto Rack, Or Cobra rack?

Just wondering because Since I converted to a Power Cobra rack and have lost quite a bit of turning radius. The throw on the rack is just not as far as the stock system. which makes the turning ratio of the car allot wider than it was.

I have an Idea for something that will bolt on to the stock spindle and correct for the shortened throw. But I don't want to re invent the wheel here. Is there already something out there that will do the same thing???

Please give me your input so if there is nothing already out there Maybe I can have several sets made.

twistedwedge

Ive got the flaming river manual pinto rack in mine...i like the way it turns. But really I cant give you a verdict on comparing to stock cause Ive got big slicks and a spool, which kinda kills my turning radius

Z RATED IROC

Don't get me wrong, I love the benefits of the Rack & Pinion steering, Especially the Power rack. I just can't believe how much it increased the turning circle of the car. The wheels just don't turn as far.

Unfortunately I didn't do a before and after comparison on my turning circle. However, It takes me 3 lanes plus the lane I am in to do a U turn.... OUCH!

I'm pretty sure the device I am thinking of having built would be able to correct for the shorter throw, and make our cars turn in a stock circle. I'm just wondering if the reduced turning circle is limited to this rack, or are all racks causing the same issues...

SLP IROC-Z

iTrader: (1)

does ur front end sit any higher with now with all of that weight taken off the front end?

Z RATED IROC

I'm sure it would have. I can't make an accurate comparison though because I went to a coil over set up.

My back end came up about an inch though. I took out all of my stereo equipment...
Had to make room for the big blue bottle...

89_3rd_gen

Your ackerman has been changed.
The 3rd Gen steering arms are not design for R&P. You'll notice R&P steering arms are straight, ours are angled. Get on some turn plates or check your tire temps and you'll see. R&P on 3rd Gen's is for mostly for drag racing. You maybe able to heat the steering arms and correct this.

Z RATED IROC

I just got off the phone with Vern at Pro Fab. I explained the device to him that would correct the problem. He liked the idea and said he will look into building them. He also said he is looking into building some light weight spindles too.

SLP IROC-Z

iTrader: (1)

awesome, im still going to swap over to the R&P steering, my stuff should be here on wednesday, i guess ill be buying his spindls and the "correction" plates.

Z RATED IROC

Yeah, Call Vern and tell him you'll be wanting those things too!
Maybe he'll get them built faster...

877-782-6470

By the way did you get the Bump steer kit with your kit?
It needs it.

SLP IROC-Z

iTrader: (1)

yeah i got the bump steer kit tooo. did he say how long itll be before those parts are for sale? id imagine itll be a while.

Z RATED IROC

He didn't make it sound like it will be too long.

I noticed that my Bear Brake calipers are almost hitting the A arm when I have the wheel turned all the way. Not hitting, but have no room for adjustment.

It may just be an issue with that particular caliper. When you get your Kit all together let me know how much Clarence you have between your caliper and the A Arm.

I'm thinking that the Bear Calipers would be the limiting factor at this point, Not the Rack.
I'm sure Vern would make some modified A arms for me if I needed them. Those plus the "Correction Plates" would take care of all of the turning issues.

I'm going to get an alignment and see how it is after that. Then we'll see what more (if anything) needs to be done.

SLP IROC-Z

iTrader: (1)

talk to him today, he said they are working on them already

Z RATED IROC

Sweet!!!

hre59

Akerman is a measurement in degrees. If you turn your wheel to the left, your left wheel will turn more degrees than your right wheel. If your steering arms on the spindle are bent the same and are the same length you will have equal akerman in both directions of steering. A normal amount af akerman is about 3 degreesfor a street car. If you want to change the akerman you will have to bend the steering arms either in or out in relation to the centerline of the car, depending if you want more or less akerman. More akerman will help on turn entry on tight corners but will cause scrub on long fast sweeping corners. What this boils down to is akerman has little effect on steering radius. As far as steering radius, if the rack is at the end of its travel and none of the parts are in a bind at full steering lock, your only option for decreasing your steering radius is to shorten the length of the steering arm on the spindle. The steering arm length is measured from the ball joint/strut vertical centerline forward to the outer tie rod end mounting point. Shortening the steering arm on a cast steel spindle is not recomended unless it's performed by skilled welder! IF THE WELD BREAKS YOU LOOSE YOUR STEERING TO THAT WHEEL!!!

SLP IROC-Z

iTrader: (1)

that makes sense. so what would be the correct thing to do? find a mustang spindle and measure from the ball joint to the outer tie rod mounting point, then have a set of spindles made for thirdgens that has the same distance from the mounting point to the balljoint?

Z RATED IROC

I see what you are saying about the Akerman Measurement.
I agree about not welding on cast steel. There is no way I would take that chance.

What I have been talking about is a piece that would Bolt to the end of the Spindle in the same place the tie rod bolts. Then it would extend back toward the hub of the spindle. (Our spindles curve out toward the wheel making room for this piece)

Then your tie rod end would bolt to that piece at a precise point, Making it Act is if you had shortened the spindle arm.
With some calculations you could correct for both the Throw, and the Akerman by where you have the new attachment points.
One simple piece, No welding. It would act much as a Bump steer kit does to correct steering linkage angles.

hre59

z rated iroc: I think your on to the fix for shortening the effective length of the steering arm. My back ground is in oval track racing where the steering forces are huge. So your mods make me nervous on the strength of your bolt on relocation point for the outer tie rod end. If you are drag racing on front skinnies than steering forces are less of an issue for you. I don't have any input on mustang spindles.

Z RATED IROC

All of the bolts used are Twice the size of the ones on the tie rod end that comes stock on our cars. I'm not at all worried about strength.

anesthes

iTrader: (12)

I've collected the foillowing data tonight:

Stock 3rd gen steering box:

Turns Lock to lock: 2.5
Inches of pitman arm travel (total) 6.
Inches of tie rod travel each direction: 3


Mustang power rack:

Turns Lock to Lock: 3
Inches of travel (total) 5
Inches of tie rod travel each direction: 2.50


4th Gen Rack:

Turns Lock to Lock: 2.75
Inches of travel (total) 5
Inches of tie rod travel each direction: 2.50

-- Joe

anesthes

iTrader: (12)

Stock thirdgen spindle, aprox 8" center to center (ball joint to tie rod)

-

anesthes

iTrader: (12)

Thirdgen spindle, modified. Approx 5" center to center, which is the same as a 4th gen spindle.

I just need to find someone willing to modify and properly weld the spindles..

bottledbird68

Having the same issue on the turbo car. Really the only complaint with the rack conversion. Definitely interested if something comes out to solve it....

anesthes

iTrader: (12)

As far as I know, the spindles are steel. So they should be weldable by a competent welder.

I'm researching more into this. I'll post my results.

-- Joe

Chris Etemadi

The people with the rack already goining, How bad is it? does it make it hard to even park the car in a parking lot?

anesthes

iTrader: (12)

I spent some time looking at the 4th gen stuff. I'm not sure if its possible, but I was thinking.. A 4th gen spindle shoudl mount to the lower control arm because the ball joint should be the same diameter.

Then you cut off the top of the spindle, drill two holes and mount a bracket for the strut. Two birds, one stone. You get the better tie-rod arm angle, and ls1 brakes.

-- Joe

anesthes

iTrader: (12)

I decided on a solution..

I "borrowed" this picture from a TGO member, I forget who, but thanks.

Anyway. Spent some time in the yard this morning measuring 3rd and 4th gens. The 4th gen spindle on the 3rd gen is possible, but the bracket VERY difficult to make.

Here is my solution. Either temporary, or permenant.

anesthes

iTrader: (12)

So I drove the car last night. Holy crap, it steers like ****. I mean, really bad..

The radius, that aint even funny.

And the 3 turns lock to lock is just junk.

Profab said if I send him my spindles, for $50 he will mod them to get the ratio back. I just hope it doesn't interfear with where the swaybar mounts to the control arm.. wtf.

Anyway. yeah it sucks. sucks hard.. I'll post more results.. Worse comes to worse, I'm going back to ws6 steering. This sucks.

-- Joe

CamarosRUS

good luck man. any updates??? and i was thinking to converting to rack and pinon but what are the benefits? is it even worth it to convert, i remember some1 saying its only good for drag racing.

anesthes

iTrader: (12)

Spindles are in a UPS truck somewhere. Should show up monday.

I picked up a cobra rack, and re-worked the shaft. So its 2.25 turns lock to lock. Should turn like a charm I hope.

-- Joe

FullSendRacing

curious how this turned out??

anesthes

iTrader: (12)

Worked great, but the steering shaft interfeared with my headers. I sold the k-member to a board member, and the rack, ujoint, and spindles to another member.

Then I stripped the car, and bought a '91, with a GTA box. woot.

-- Joe

FullSendRacing

LOL, I've still yet to hear of someone running a rack on the street and enjoying it. I wanted to do a rack setup for roadracing, but maybe I'll just stick with a performance box, and forget about it....

dennisbernal91z

iTrader: (2)

I wanted a Rack soooo bad, partly cuz the slick look it gives and I love changing anything I can on the car. But if it is turning out to be such a pain, then I guess I will stick to my aftermarket manual box. Very light weight too.


If there is a fool proof way to change to R&P let us know

bottledbird68

It seems to me no matter which way you look at it switching to a rack is a PITA

SLP IROC-Z

iTrader: (1)

its not worth the trouble unless its a trailor queen or track only car. been there done that!

dennisbernal91z

iTrader: (2)

Hey SLP IROC-Z .... I see that you painted a lot of stuff on your car domain site. Could you fill me in on moredtails about that. I live neer Boston and am gonna need paint in the neer future. Do you know any good places? Do you do side jobs? Is it really hard to do it yourself? THX


-Dennis

StreetRoc85 350

There are not enough words in the english language to describe how stupid that would be. When you heat metal, you change the way the molecules are aligned and alter the properties of the material, namely, its brittleness and ability to handle high stress loads. Heating/bending/cutting any steering component is just begging for trouble. It may be fine the first time you drive it, it may still be fine the 25th time you drive it, but what happens on the 26th time? the 100th time?
What happens when you are forced to swerve suddenly or hit a speed bump? All of this puts tremendous stress on your steering components.

FAST CAR + QUESTIONABLE STEERING = BAD!!!!!

Please for the love of g*d and the respect for the rest of us on the road DO NOT GO HEATING AND BENDING YOUR STEERING SYSTEM!!!!!!!!!!!!!!!!!

BlueBeast

where did everyone get there stuff to convert. i am in the middle of ordering the rack and i need to know what other parts i need for this convert. any help will be great thanks

Z RATED IROC

A Friend of mine is parting out his car and it has a complete Rank & Pinnion conversion, K Member, and Coil over conversion. The system is almost brand new! Maybe 500 Miles on it.

Send me an E-Mail for details.
zrated@comcast.net

Dave88z

Has anyone come up with a solution to the decreased steering angle?

matt_p

Just need to find someone that makes a rack that has the amount of travel stock thirdgen steering has. If someone does

Dave88z

The problem isn't the amount of travel, it is the spindle design. The arms need to
be shortened like a 4th gen spindle to increase travel.

matt_p

Thats the dumbest thing I've ever read.

The racks being used do not have the travel required to be used properly with the thirdgen spindle design. It would be better to find an appropriate rack than cutting a welding a spindle.

Dave88z

Don't you think that if they had a rack with enough travel everyone on this damn board would have bought it already! I agree that the stock spindle should not be modified, but it would be cheaper to have custom spindles made then a custom rack and pinion>

matt_p

Cobra / MGB Manual Rack & Pinion

Has the travel, just isn't power.

anesthes

iTrader: (12)

Heh. new guys

The rack doesn't have the same amount of travel as the box did.

The arms are too long for use with a rack. Arms for rack cars are way shorter.

The rack you linked us to, is 3 turns lock to lock, not power, etc. Might as well use a manual S10 box.


Since my last post in the thread, I sold the '91 and bought a real car. It seemed I spent 10 years and tons of money trying to make my car drive, steer, and handle like the one I got now. Took me forever to figure out that I just needed to sell everything, and buy the right car.. Guess I was the retard.

-- Joe

matt_p

No one called you a retard. Where did you come up with that? The idea wasn't dumb, just the wording. He said the probelm wasn't travel. Then said it was.

Perhaps your right and it is best to stick with the regular steering box.

Cutting the spindle arms seems to be the only answer. Just gotta make sure it is done properly.

anesthes

iTrader: (12)

I'm a retard for spending soo much time and money on that car. But thats another story.

The problem is it wasnt meant to go there. The arms are too long for a rack, and the racks travel is too short for those arms. Just a bad combination, kinda like a bad relationship.

Stick with the regular box





(or buy a vette)

-- Joe

Dave88z

Or just find a company willing to make a custom spindle. I know for a fact that there are racing spindle/strut assys out there, but they cost a fortune and are pretty much race only items. If companies like belltech can make a drop spindle they should be able to make a shorter arm if there is a demand for it.

anesthes

iTrader: (12)

Yes you are right, but then you also need a company that makes a reliable k-member, you then have the issues of the rack potentially hanging too low, you have bump steer issues, etc.

I understand you're thinking outside the box, but I've tried everything available.
Theres a point where you gotta decide what you want to spend your money on. How important is rack & pinion steering anyway? It's great on my Corvette, but thats because the suspension was designed around it.. (and the 275/40/17 tires).

-- Joe