Rack&Pinion

[King Nothing]

Can I install a Rack&Pinion on the stock front subframe on my 73 Camaro without welding or fab work for it to bolt up or for clearance?

[bret]

Ask lots of questions:

Steering radius loss...the manufacturer should have turning angle data
Bumpsteer...get actual bumpsteer graphs from the manufacturer
Bracket flex...your trying to twist big tires on a heavy car
Strength of the rack itself...many of these racks were Originally designed for much lighter cars with much smaller tires

It is extremely tough to get a proper rack in the proper location on a car that was not originally designed to have one.

[King Nothing]

Ok so I need an aftermarket subframe for the Rack&Pinion for other reasons than installation onto the subframe.

[Ron Sutton]

I agree with everything Bret said & add one clarification.

In most cases ... most ... you can't just install a rack & pinion into a car designed for a steering box ... and have it come out correctly. Usually, the frame & crossmember design won't allow putting the rack where it needs to go.

So just installing the rack "wherever it fits" usually leads to incorrect steering tendencies. Which leads me to ask why we're doing it in the first place.

I love utilizing rack & pinions in my "clean sheet" front suspension designs. But the only real advantage they offer over a modern steering box system is lighter weight.

Is your goal to save some weight ... or improve your car's steering traits? If it is steering you want to improve, post up specific goals & I may have some suggestions.

[King Nothing]

My apologies guys, I should've stated that in the first post. I am going for a pro-touring style build, I'll autoX the car and do road courses also. The car will be driven on the street for weekend cruises and car shows. I plan to run at least 12" rotors up front with either 17" or 18" wheels.

[Ron Sutton]

Originally Posted by King Nothing

My apologies guys, I should've stated that in the first post. I am going for a pro-touring style build, I'll autoX the car and do road courses also. The car will be driven on the street for weekend cruises and car shows. I plan to run at least 12" rotors up front with either 17" or 18" wheels.

Gotcha. My suggestion would be ...
A. If, and only if, you swap in an aftermarket clip at some time, would I run a rack, so it is designed in.
B. Otherwise, with your stock clip, I'd simply update the old steering box to a new 670 Series steering box with the ratio & feel (determined by the servo torsion size).

This series 670 box was designed by Delphi & manufactured by Saginaw. It is light years ahead of the old Saginaw steering boxes in both design and materials. Steering will be tighter longer. Their new design will allow you to pick ratio & feel separately, using rack & pinion style torsion bar technology.

You can get a brand new, 12-1 ratio / .210" T-Bar (Medium-light feel) blueprinted box that bolts into your car for $749. You'll need an adapter rag joint or u-joint. (Rag joint for street driver only / U-joint for performance).


If your steering system needs better ...
* Bumpsteer: I'd buy or make a bumpsteer kit to correct it ... and/or ... possibly change the center link to help achieve the bumpsteer target
* Ackerman: some gain can be had by converting to an aftermarket centerlink & rod end style tie rods ... with spacers moving the inner tire rod pivots points.

[King Nothing]

And running larger brakes and tires can be done with the stock subframe? Would the tires clear the subframe on a full clock to the left or right? I'm not worried about the fenders because they will be flared.

[dhutton]

Originally Posted by King Nothing

And running larger breaks and tires can be done with the stock subframe? Would the tires clear the subframe on a full clock to the left or right? I'm not worried about the fenders because they will be flared.

I think you need to define larger. What size tire and wheel width/diameter are you calling larger?

Don

[King Nothing]

Originally Posted by dhutton

I think you need to define larger. What size tire and wheel width/diameter are you calling larger?

Don

The smallest would be 17x9 wheel and tire would be 275/40/17, the largest would be a18x10 wheel with a 295/35/18 wheel.

[dhutton]

Originally Posted by King Nothing

The smallest would be 17x8 wheel and tire would be 275/40/17, the largest would be a18x10 wheel with a 295/35/18 wheel.

I don't think you can put a 275 tire on an 8 inch rim. Needs a minimum of 9 as far as I know. Anyway you can fit a 275 tire on a stock subframe using the Ridetech Tru-Turn setup if you nail the back spacing. 295 means an aftermarket subframe and most likely widened inner fenders as far as I know.

Don