Technical Trifive Gasser Steering Boxes & Arms.

Every time I have a question on anything you guys have come threw & saved me alot of time, money and frustration, thanks. Got '57 Chevy truck axle ready to mock up under my '57 Chevy 150, drilled axle holes, "fitted" '61 Corvette drum brakes to truck spindles, still need to drill backing plates. Question, need info on what type of steering box and arm to run. Remember pics are a plus! Thanks!

 

Are you planning to move the steering in front of the axle since you are planning to run a BBC? It will give you more clearance, especially if you are setting the engine back any.
In wouldn't use anything smaller than a Saginaw 525 box. I've heard of some guys running a reversed Vega box, but I think they are too small for a heavy car like a tri five chevy... especially with a BBC.
I know my car isn't a tri five, but if you want me to send pictures of my steering setup. I will. I'm using a 525 box and cross steering with factory style tie rod ends (no heim joints) and factory end links on the spindles. The only real difference is I am running a tube axle.

 

I'd use a 525 box myself and mount it in front of the axle with pitman arm pointing back. You'll likely need to grind the alignment off the pitman arm to turn it 180 degrees, but that's easily done with a small round file.
Of course the tie rod will go behind the axle, but drag link will be in front, and a steering arm pointed forward off the top side of the spindle.
Here's the setup I have on my '39 Chev:

 

I only use the Vega box on Deuces and even that it has to be a quality one. I use 525 on '35-'40's. Was hoping to adapt what I have laying around like a '57 Chevy truck & pass. car box, but if there's a handful of good reasons not to I will listen! I thought if going the BBC that there would be enough real estate to get by? Looks like I need to mock up the front suspension & sub frame first.

 

One of the advantages of having the steering box in front of the axle is so the drag link can be parallel going to the passenger spindle without having to worry about oil pan clearance.
I'll try to post some pictures of my set up on here tomorrow. Unfortunately I won't be home till after dark today.

 

First choice is to keep in front of the front suspension area clutter free if possible, but realize modifications will have to be made. Looks like I am jumping the gun a little. First rule of hot rod building is mount what has to go where it goes and modify to fit the surrounding parts. Will be back after the stub frame, axle & springs are mocked up under the fenders.

 

if you want to use cross steer, you could probably use the original steering gear. Drag link to oil pan clearance might be tight.

 

Correct, If the clearance is to close, the oil pan can be modified, a lot of guys have successfully done that.

 

If you're planning on "Cross-steer" look at an Aisin Steering box from a RWD Chrysler Sigma.
They are available in Power and non-power steering.
The sector is tall enough so the top of the box sits above the frame [so you can shift the whole box further to the L/H side allowing for a longer drag link ]
The steering column is also further to the left above the frame allowing for header clearance




I trusted the Sigma Box at 176 mph in my race car.
Here is a power steering variant I adapted into a C3 Corvette


The Pitman arm can be clocked 360° on these boxes.
The Sigma box is also available in Starions and L200 /D50 pickups

[also a C3 Corvette box would also be a good choice]

 

The issue with going with a stock box, or a behind the axle box is pan clearance, and drag link angle. If you want to keep the box behind the axle it's going to mean you'll have a steep drag link angle which will create bump steer issues. Bump steer is scary as Hell when it happens.
By going up front you can get the drag link almost perfectly level, unless you go nuts with the frontend height. Zero bump steer, and no clearance issues anywhere. And the bonus is no heat from headers affecting the steering box.

 

My main goal is trying to make it look like it was built in the '50's-'60's, with parts of that era. Keeping it simple and safe, maybe I am dreaming! Already figured out that I better get it all mocked up under fenders with stub frame & BBC mocked up than figure out what can be done. With motor/trans placement, steering, headers, etc. At the most I may run a pan hard bar if not to cluttery looking or in the way of BBC pan.

 

Then stock steering box and set engine back.

 

This '57 Truck axle has a stock drop to it as opposed to a "straight" axle so hoping that will give me some free real estate in the BBC pan area.

 

^^^^^^^^^^^^^^ Well yes I do & it was sitting 3' away from my axle^^^^
Ever have so much crap that you forget what crap you have? 1961 C1 Vette, Will give this a look see! Thanks!

 

How would this work when the pitman arm operates inside the frame vs the outside?

 

Thats what I am trying to figure out now, hoping the steering geometry will work when I mount the pitman arm outside the frame rail ( box upside down). Cross your fingers that when the steering shaft is turned to the right the wheels go right instead of left!

 

Will the sector shaft poke thru the frame enough? If so, why not a truck steering box? Just throwing it out there but not a go to for me.

 

That I don't have for a look see, a truck box. This isn't going to be doing any road course. was wondering though what the steering ratio of a truck verses a pass. car '57 would be.

 

You asked!

 

55 Frame with 1958 3100 axle, custom springs and Borgeson 525 box.

 

Early Land Cruiser and Hilux [Straight axle] 4 x 4 boxes are correct for side steer.


The Corvette box with the geometry shown above will need to be reversed [The third arm in that drawing is opposite orientation to the steering arm "fork" on conventional side steer]
When the drag link goes forward it steers right, on a normal side steer when the drag link goes forward it steers left.

 

Is it me or my mind losing it. Is that axle or parts of it-in funny. Seems to me the axle should decapitate the chicken, before tie rod.

 

Appears to have the tie rod up front, so I hope the steering arms are outside the kingpins to have the correct Ackerman angle? It's much easier to attain correct angles with the tierod behind, but it can be done in front if your wheels have enough offset to not hit the steering arms.

 

Not a period correct steering box, but the old late 70's Ford RangerMazda PU boxes are fantastic. They sit outside the frame rails, and are very tall so easier to get a flat drag link angle with. I found one of these boxes at a local wrecking yard when I was building my '63 Falcon gasser and it worked fantastic. Did it front side steering, and being outside the frame rail it didn't interfere with anything. The box part offsets over the top of the frame so connecting a DD shaft and joint to it is a nice straight shot. No clearance issues at all, even with a BBC in my old Falcon.

 

"Moriarity, post: 15406779, member: 218"] Shouldn’t that vin tag be put on the car?
On the To Do list it's #17 I will get to it!