Thread: Rack and Pinion

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My car has 31,000 miles and the steering feels sloppy. You have to steer it back to center and you have to steer it to keep it going straight. It's a Vega cross steer box. Straight axle on a TCI chassis.

Anyone have a rack and pinion installed in their 32? Did it improve the steering? Any installation problems? Brand? Thanks.
Dan

You didn't mention if this was an all of a sudden thing, something gradual over time, or ?

Normally for not self centering I would suggest you have your caster checked, If it's always been like that it's probably not adjusted correctly. If it's all of a sudden inspect for worn radius rod bushings, a failing bracket, bent axle, all the front end components actually.

Rack and pinion has been done on straight axle cars, but more fail than succeed at getting them to work right IMO. Problem is, if you mount the rack to the frame as the car bounces up and down it forces the spindle arms in and out, effectively steering the car (bump steer). If you mount it to the axle you eliminate that problem, but you add a bunch of unsprung weight to the car. The racks also don't look real good sitting back there.

A properly installed conventional steering box, in conjunction with a panhard bar and proper geometry usually will produce a car that goes straight down the road and that will steer like it should.

Don

When I read your post the first thing that popped into my head was that you need more caster, as Bob said assuming everything is tight. I would add, your caster angle needs to be relative to the ground, not to the chassis. According to an article in R&C http://www.rodandcustommagazine.com/...ils/index.html stock caster was three to four degrees, but with big & littles a degree or two is right. More caster = more stability, but also eats into your turning radius - look at rail dragsters or a radical chopper.

A guy here locally put a Uni-steer rack on his, sez it works great. Think he got the whole set up from Speedway Motors...

If ya want a rack, slap a Maval Unisteer 1/2 rack on it and be done with it.
Have done over 30 of them in the last 6 years.,you'll never go back to a vega style.

Thanks for the replies. It's been that way since I bought it a couple years and a couple thousand miles ago. It does have a Panhard bar and I added a So Cal steering dampner. Not too long after getting the car I changed the wheels and tire to a big and little and don't recall it making any difference. If you're sitting in the car and not moving, there's about 1/4 turn play in the gear box before there is any wheel movement. My Mazda3 has zero movement. I'll check the castor but I feel that is too much play in the steering box.

Originally Posted by DanM

Thanks for the replies. It's been that way since I bought it a couple years and a couple thousand miles ago. It does have a Panhard bar and I added a So Cal steering dampner. Not too long after getting the car I changed the wheels and tire to a big and little and don't recall it making any difference. If you're sitting in the car and not moving, there's about 1/4 turn play in the gear box before there is any wheel movement. My Mazda3 has zero movement. I'll check the castor but I feel that is too much play in the steering box.

Way to much play in the box.
Crank down on the adjuster on the box to lock it, then backoff 1/8 turn.
If that don't solve the problem, box is junk.

However---if the car doesn't have stability----it needs toe and caster set--also with a panard bar, the shocks have to control the bounce or the panard bar will move the axle back and forth

Thanks everyone for your input. Don, I took your advise and adjusted the box and now there is normal play. Haven't had a chance to drive it yet. I'll also get the caster checked since installing the big & littles reduced the caster.

I'll probably get a Maval Uni-Steer 1/2 Rack to add to the winter projects.

Dan

By chance your box doesn't have "Flaming River" cast into the top? I have one on mine and I'm having similar problems right now. Through various internet searches I have discovered that Flaming River Vega style boxes seem to have a bad rep for wearing out prematurely. My car just turned 10,000 miles. 9000 were trouble free, but in the past 1000 I've had to adjust the slop out of my box twice.... and it still doesn't seem to be as good as it was when new. I'm thinking the box is headed south.

Joe, sounds like it's time for a 1/2 rack !!!!!!

i have a " flaming river " on my stang and i have a 1/4 turn play .. 450 bucks wasted ..

Originally Posted by joeybsyc

By chance your box doesn't have "Flaming River" cast into the top? I have one on mine and I'm having similar problems right now. Through various internet searches I have discovered that Flaming River Vega style boxes seem to have a bad rep for wearing out prematurely. My car just turned 10,000 miles. 9000 were trouble free, but in the past 1000 I've had to adjust the slop out of my box twice.... and it still doesn't seem to be as good as it was when new. I'm thinking the box is headed south.

It's a Saginaw 140 (Vega) box.

Hey Don! got a question about the half rack. I am installing one on my 32 to replace the vega box,i mounted to the vega mount, it is not parallel to the tie rod or on the same plane,should they be? I would have to move the rack 3/4" forward and down 1 and 1/2 inches. thanks Pete

Originally Posted by DA34GUY

If ya want a rack, slap a Maval Unisteer 1/2 rack on it and be done with it.
Have done over 30 of them in the last 6 years.,you'll never go back to a vega style.