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The new mastercylinder arrived Monday but I need to sort out the steering before I can install it...so I ordered the $160 dunebuggy rack I was eyeing:


Its everything you'd expect at that price and more! There is quite a bit of lash and no way to adjust it but its about perfect travel wise and not the and about 1.62 turns lock to lock which I think is near prefect (they said 1.5 but that's a lie). I took it apart:


On the plus side the rack teeth are induction hardened and the pinion is hard, the bellows seem fine.

On the minus side no bushings in the housing and while it appears to be designed for a rear pinion bearing there isn't one. The rod end are 3/8" which would be only marginally adequate. And of course its mossing about 2 feet on the right side.



I stared at it for a bit trying to decide if its worth messing with...I have a plan.
1) add a rear pinion bearing
2) add rack bushings to the housing and off-set then slightly to yield a high pre load on the pinion. That will fix the lash and should it ever return replacing the bushings should again sort it but I can't imagine it will get that kind of use
3) Rethread the rack ends 12mm or maybe 1/2"
4) thread the OD on the right side of the housing
5) Add a right side rack extension
6) add a right side housing extension

I'm guessing that's $50-$100 of material then I can worry about how to install it.

There is definitely an extra quick ratio 308 rack hiding in there. I was concerned it seemed fragile but it's probably stronger than stock. I was horrified to discover the tierod ends are 1/2-20 thread....oh the shame of it....



The rack is 22mm, of just under 7/8. I was going to make a thread on extension but 22mm is hard to come by and it would be WAY easier to just slip a 1" OD x0.62wall tube over the end and weld it....I think 4130 comes .065wall so stronger and would fit better. The I found some 1" sch 40 aluminum pipe that has a 1.05" ID to make the housing extension from. This should work.

I ordered a 2" piece of 4130 tubing to extend the rack from aircraft spruce, $10+$10 shipping was about the cheapest I found so a few days for that.

The new rack had rod ends which I think are a little small and would make adjusting toe a pain. I spent some time looking at different inner tie rod options and ordered some on amazon to see if I got luckily because I was completely not understanding I could just use the ferrari parts and and have to adapt nothing. I just need to tap the rack and install studs. Amazon parts canceled.



I will need to use larger bellows to go over the tie rod ball, but luckily I have ferrari bellows, I'll need to make a sleeve to up size the rack housing. Easy enough

Then last the ferrari rack pinion is angled like 5deg and the new is straight so I need to figure out where exactly I should position the rack to get everything happy about the angle change. I guess that is the next step so I can do the housing work.

Is this what you were thinking then? Am I on the right track?

I was in the shop most of the day....but you know....

First I really needed the fab table so I moved the crank and rods to the printer bench and finished deburring the pistons before moving them


Then removed the appendage they intended as the mount.



..and couldn't help myself I filled what was left of the bolt holes and dleaned it up



At this point I noticed the gear teeth are cut not ground and decide I lap them a bit to smooth them out


The rear of the pinion wasn't really any size...a fat 15mm so I had to polish off a few thou to make it fit t5he bearing correctly


Then add the rear pinion bearing and a couple notches thinking they will give me at least a change of being able to remove the bearing



The sleeve for the front bearings was kind of loose so I assembled that with red loctite and and kind of spun it hoping that carters it.



I kind of futzed around with the rack and blocks and shims to see how much clearance causes how much rotation in the rack and decided I need to move the rack 0.15" closer to the pinion so into the 4 jaw chuck on the lathe and indicated it true but .015" off center and got cutting. I bored the center so the rack had room to move, added a bushing and threads to the one one, flipped it then shortened the other end 1/8" because after fitting it in the car that end was a little long, then cut the bushing bore, then added an OD I can press an adapter for the the boot onto.. And here is where it sits.




I probably could have move the rack another few thou but its smooth and the lash is gone. tomorrow I need to shorten the rack on the driver's side and add a stud so the tie rod installs in the correct position. From there I can finish the housing extension and test fit it in the car which will let me start figuring out what I need to order to connect to the power unit and the steering wheel. It should start to look like something tomorrow.

I knew there was a 308 rack hiding in there.



The tube to extend the rack itself appears to be coming friday but with the housing and fitting in the car done I can get onto sorting the steering shaft. And I still need to add rings to mount the bellows

I started today getting the drivers side tierod on the rack which meant shortening that end of the rack. I suspect the rack was meant to be symmetric....but one end was shorter than the other by nearly 1/2" so I shortened the short side


Drilled and tapped M14


Then drove a bolt in and cut it to length


and the tie rod fits


Then the housing extension with a thread to mate to what I cut on the housing and call it a night.

Like everything else in this thread, this is very far beyond anything I was thinking. Amazing and inspiring work, as usual.

The 1" tubing I needed came so I welded it to the rack, welded in a bung and tapped it -note I stopped the tap just short of threading all the way through the bung....so when I drove the bolt in it binds and stays.


Then.....well I thought is was a decent fit tube to rack and I could just weld.....yeah...so I heated it up and straight5ened it out.


Then polished it up and it looks right


The tubing after polish was almost 1.002" and the bushing is 1.000" so I "honed" the bushing


and there it is about ready to install.


It tight and smooth (after I sanded some sharp edges off the rack gear). It still need rings on the ends to mount the bellows but I want to leave the bellows off until the steering linkage is done so I can check center more easily. As is its 4.6lbs, exactly 3lbs lighter than stock. The keen eyed might have noticed I chickened out on the threaded housing extension because I just seemed too thin so I welded it, easy enough to cut the weld if I wear out the inner bushing even. Hopefully the steering shaft bits I ordered will be here tomorrow so I can keep rolling.

The 17" 246ish wheels I made for a 308 owner arrived and he got them installed. That was a fun project.

The steering parts came and all fit correctly but I didn't make much progress. Lana needed shelving that was hiding behind scaffolding, I got another 1 off wheel inquiry which looks like it will become a job, a buddy needed headers evaluated in the sim software and while I was doing that my son started pinging me asking how hard it would be to make a custom exhaust for his bike so we chatted about that a bit and then I leaned the plan is titanium.....my baby, the the little boy that was born 6 months before I started the V12 project wants to built Ti headers...... I was so proud it nearly brought a tear to my eye.

All that aside I did start building steering linkage and got wondering if there was a hard way to do it? hmmmm.....got it! I could make the 3/4" shaft 22mm with lots of weld!




That's as far as I got. Tomorrow.