[max 93]

I bought an Iroc steering box from Napa and I am wondering if it is really a quick ratio box. It seems to be 2 3/4 turns lock to lock. I thought they were supposed to be 2 1/4. Is it possible that I got a regular Camaro box ? Or is this correct ?

[Overkillphil]

Probably the same deal as GM. After a certain number of years, GM consolidated the various P/N's into one generic box.

[Grand73Am]

The number of turns doesn't tell you what ratio it is, so you can't tell by that. It's how fast it gets there. For example, a 12.7 constant ratio box(iroc), and the regular variable ratio box, will turn about the same amount of turns, but the constant ratio will be faster off of center than the variable, which is slower off of center, but speeds up the more it's turned.

[pont3]

Plus, I've never heard of a GM box with 2.25 turns lock to lock. I don't think there's a steering system of any type with a ratio that fast.

[cutlas]

2.25 turns lock to lock is correct for an IROC. The box you received could have been from a Z28. I have the IROC box in my 67 Firebird project. It was 2.25 turns when I checked it on my bench before installation.

[Kell]

I put the IROC box in mine, the steering effort is almost too stiff, I think mine was 2.5 turns lock to lock (installed), it looks like you can get the code off the box to tell which it is: WS is the regular camaro, XH is the Iroc according to this:

http://www.carcraft.com/techarticles..._steering.html

[max 93]

It is a napa rebuilt box. The ink codes are not there

[Kell]

I think it's stamped on, very lightly, see page one on the link

[max 93]

Originally Posted by Overkillphil

Probably the same deal as GM. After a certain number of years, GM consolidated the various P/N's into one generic box.

This seems to be what happened. Napa has the same part number listed for
A mont Carlo ss

[Qball]

Max, what is that IROC box going into? Will they fit in a 67 A body and, if so, will it affect the turning circle?

[max 93]

I am putting it in a 68 firebird. It will fit an a body. Not sure about the turning radias.

[rolling money pits]

Originally Posted by Qball

Max, what is that IROC box going into? Will they fit in a 67 A body and, if so, will it affect the turning circle?

i have no idea how the napa, and others, rebuilt boxes are set up internally.

but, it's been noted that an F-body box will increase the turning circle due to the internal stops being different than an A-body box.

that being said, i dont know in the world they could supply one part number box covering various body types - A, F, G, bodies, etc. something's gotta give there...

[cutlas]

For an A body the hot ticket seems to be the 1993 to 1997 Grand Cherokee steering box.
Max 93, when you get your steering box sorted out, check to make sure you hit the steering stops on the control arms when your steering box is at the end of its travel.
I needed to change my pitman arm to the longer one to make this happen.

Joe.

[blue bayou]

Ok guys. I'm wanting to make this modification to my '69 bird. What all do I need to change? Cutlas you mentioned going to the longer pitman arm. Would that be the stock manual steering arm or the stock power arm? Any other modifications necessary?

[cutlas]

blue bayou, from what I have seen GM used different pitman/idler arm lengths combined with different steering arms (I am not sure if steering arm is the proper name but it is the part attached to the spindle) and steering boxes to get the steering ratio. My 67 requires the longer 5.75" pitman arm (TRW 18770) to get the steering to go to full travel against the steering stops at the same time the steering box was at the end of its travel. With the shorter pitman arm that was in the car when I got it I had almost a 1/8" space between the steering stops when the box was at full travel.
Here is a link that explains it better.
http://www.pozziracing.com/camaro_st...eering_linkage