FJ40 Power Steering Conversion - 80 Series Power Steering Box Kit?

[youngmanchego]

I don't remember the exact recipe. I think I used a combination of 3rd Gen 4Runner and 2nd Gen Tundra shafts to get the final product. I do remember cutting two dissimilar shafts and welding them together to make what I needed. There may be details buried in my FJ40 build thread.

Ah okay I had fingers crossed it was a single unit. A boy can dream. I’ll do some digging. Cheers

 

[Stubby]

What are you using for your intermediate shaft here?

Get a universal telescoping shaft from Borgeson.....just need to get a Double-D to round shaft universal for the steering column end and Double-D to 80 series spline for the box end. Cut to length and works like a champ. That's what I put together for my 80 series P/S conversion.

Steering Shafts

Manufacturing quality steering components since 1914

www.borgeson.com

 

[archie73]

What are you using for your intermediate shaft here?

I used the intermediate/collapsible shaft that came with my 80 box. I used a correctly splined Borgenson ujoint with a double D. Then just ground the stock steering column to double D where it came out of firewall.

 

[youngmanchego]

I used the intermediate/collapsible shaft that came with my 80 box. I used a correctly splined Borgenson ujoint with a double D. Then just ground the stock steering column to double D where it came out of firewall.

Is this the one? Minus the firewall brace and rag joint of course. I can then do a yoke-to-yoke splined joint with two 60 series intermediate shaft ends so both ends of the 80 column have splined u joints. Do you know the length of the 80 column you used? I’m using a 55 series inner column bc it bolts right into the 40 tube and can be supported with a bearing at the firewall and has a splined end.

 

[archie73]

Is this the one? Minus the firewall brace and rag joint of course. I can then do a yoke-to-yoke splined joint with two 60 series intermediate shaft ends so both ends of the 80 column have splined u joints. Do you know the length of the 80 column you used? I’m using a 55 series inner column bc it bolts right into the 40 tube and can be supported with a bearing at the firewall and has a splined end.

View attachment 3590911

It does look like that. I didn’t get the bearing/firewall plate or the rag joint. I put the pictured ujoint at the box and used the Borgenson spline/DD Ujoint to the stock 40 shaft.

 

[youngmanchego]

It does look like that. I didn’t get the bearing/firewall plate or the rag joint. I put the pictured ujoint at the box and used the Borgenson spline/DD Ujoint to the stock 40 shaft.

Oh rad okay. So if that was the shaft you used and you put your box just in front of the shock tower, I should be golden. I also have a bit of length out of the fire wall with the 55 inner column, not unlike your setup from what I can tell. If all else fails I’ll never have to cut the original inner column so a revert would be no problem.

 

[youngmanchego]

It does look like that. I didn’t get the bearing/firewall plate or the rag joint. I put the pictured ujoint at the box and used the Borgenson spline/DD Ujoint to the stock 40 shaft.

Any chance you could measure the length of that shaft? If it’s a big push, no worries

 

[archie73]

Any chance you could measure the length of that shaft? If it’s a big push, no worries

I’m out of town til Monday, so it won’t happen til then. I believe it’s a stock 80 intermediate shaft. I notched the shock mount to make room for the point at the box. I didn’t modify the 80 intermediate shaft, just the 40 column.

 

[youngmanchego]

Here are a few shots of my conversion:

View attachment 2179801View attachment 2179802View attachment 2179803View attachment 2179804

This is the spiffiest setup I've seen. The custom vents for the PS cooler, *chef's kiss*. I'm scratching my head though. How did you clear the radiator support without a spacer for the 80 box on the outside of the frame rail? Any additional pics would be greatly appreciated.

 

[lelandEOD]

The box clears the radiator support without spacers; however, in order to clear the support I had to cut a relief notch in the shock tower to move the box rearward just enough to clear it.

 

[youngmanchego]

The box clears the radiator support without spacers; however, in order to clear the support I had to cut a relief notch in the shock tower to move the box rearward just enough to clear it.

Ahh okay, so its just nestled a little further back towards the driver. Thanks!

 

[SebBuilt]

Calling on some of you for some $.02 before I head into the shop to make SH!T happen. Working on finalizing steering for this 40 series and I am putting in a 60 series box with a flat pitman arm.

Background: 2.5" lift, SUA, GM 1 Ton TRE Over The Knuckle Y-link steering into the toyota arms (I have gussets for them to be welded on...)

I am preparing to make a frame notch and plate the inside/outside of the frame, drill/sleeve, and tuck the 60 series box up as high as the bottom of the frame rail sits flush to keep the drag link and tie rod as close to parallel as I can. I'll call the top-down view angle the "overhead included angle" for the sake of this question. While I am fully prepared to do this and everything lines up to clear, I can't help but notice that in the past people would do saginaw conversions and the included angle (the angle you see from the top-down birds eye view) seems extremely severe in almost every well documented example.

I could completely avoid notching the frame and doing all of the work to tuck the 60 box high and tight, but my question is have you all ever noticed severe effects from the drag link sitting forward at some angle relative to the tie rod? In my head I can see it causing some pretty wonky tie rod roll, and possibly some bump steer.

@cruisermatt @POPO AGIE @lelandEOD @archie73

Anyone have a reason to argue for pushing the 60 box forward of the tie rod instead of the frame notch and tuck?

The drag link angle relative to the tie rod in the conventional way you would measure is only 4.5 degrees (looking at it from the front).... Should me minimal bump steer attributed to that.

Thanks

Possible tuck of the steering, would go a bit higher and further back to clear the sector shaft.

Frame plate to be

Alternative: 60 Box forward, no notch, tie rod clears just fine put it pushes the drag link end up to the front at a bit of an angle....

This to me makes an unfavorable angle and weird arc between the drag link and TRE... Curious to hear opinions...

Top down view; This looks somewhat like the angles I've seen on people's SAG conversions.

 

[cruisermatt]

You are overthinking it.
Switch to a regular 80 series pitman arm.
Mount the box where they are normally mounted on a regular 40 series conversion.
The axle will not actually travel up that far.

 

[SebBuilt]

You are overthinking it.
Switch to a regular 80 series pitman arm.
Mount the box where they are normally mounted on a regular 40 series conversion.
The axle will not actually travel up that far.

I'm definitely overthinking it to a degree, with intent. I don't want to have to ever come back to it!

This is a clean slate. Aqualu frame as well. There is no rise in the frame where a normal frame would have rise and clearance for the box to mount and for the tie rod not to collide IMO.

What benefit would you see to the 80 pitman?

 

[cruisermatt]

Drag link vertical angle. The 80 pitman arm has some drop so the drag link will
be closer to horizontal at ride height

And I see what you are saying, but things don’t really get that close together on a regular 40 build like this. When I say this is a “normal” build I mean you still are going to have 33” tires, full fenders, stock 40 axle housing, these are pretty normal leaf springs, etc.
it’s not linked, cut fenders, wider axle, 37-40” tire

a 33” tire would be way in the fender by that point.

 

[SebBuilt]

Drag link vertical angle. The 80 pitman arm has some drop so the drag link will
be closer to horizontal at ride height

And I see what you are saying, but things don’t really get that close together on a regular 40 build like this. When I say this is a “normal” build I mean you still are going to have 33” tires, full fenders, stock 40 axle housing, these are pretty normal leaf springs, etc.
it’s not linked, cut fenders, wider axle, 37-40” tire

a 33” tire would be way in the fender by that point.

Oh yeah, I think the trade off in having the flat pitman is worth it. I'm too worried about going 3/4" drop.

You don't tend to see an issue with the drag link horizontal angle?

That is my main concern. If I mount the 60 box as I had it before, then things clear no problem and I won't need an 80 pitman. At ride height, vertical drag link angle is minimal.

Horizontal angle shown, I think it looks exaggerated here.

Vertical angle you described is not really a concern.

At ride height I'm 3-4° which is negligible

I appreciate your $.02.... more privy to Toyota pickup / 4Runner SAS setups with a forward IFS box and reversed pitman arm

 

[POPO AGIE]

My set up has similar angles

 

[SebBuilt]

My set up has similar angles

Your setup really intrigued me.

I realized you ran your 60 box quite far forward and it prompted me to see what that would look like.

Are you running and driving with that setup yet?

 

[pb4ugo]

I had sag steering for years and didn't care for the "horizontal" angle. I think somewhere i read an angle like that can contribute to bump steer, but it wasn't the reason why i changed to scout steering. I built a tre over steering arm y link. It's a dana frt end, built b4 alloy birfields were available, and a 4" lift. I think you need a drop pitman arm of some sort and put the box in the conventional location for the mod. The 3rd pic in post #122 is not realistic, bolt the axle to the spring and see what happens.

When i setup my 2nd 40 for scout steering i didn't want it set it up with the one suspension in mind. Thru the years you or someone else might be using something else.

 

[cruisermatt]

It’s fine, it’s like that for everyone who has a 60/80 conversion