1972 Datsun 240Z project, aka Paddy

[datsunfreak]

26 minutes ago, shlammed said:

I find that a lot of people suggest wheel diameter size for wheel face clearance of a caliper.  Looks like you lucked out that way with this combo!

 

It was definitely luck. The way these wheels are built, the spokes are really far away from the wheel mounting face. Downside is, it makes them look like a wimpier offset than they really are, but it means TONS of caliper clearance. 

 

Between the caliper and the wheel's barrel, it looks like I have at least 1/2" clearance all around. I have not checked the face side yet (need a stunt hub for that), but when I dropped the rotor/caliper in you can tell the rotor is laying flat against the wheel mounting face. So the caliper is either not touching the spokes, or is only barely touching. Meaning worst case I will need a 5mm spacer behind the wheel. 

 

I am very excited about this. 😁

[Stoffregen Motorsports]

32 minutes ago, shlammed said:

I find that a lot of people suggest wheel diameter size for wheel face clearance of a caliper.  Looks like you lucked out that way with this combo!

Yes, calipers and wheels spokes are often the issue.

 

I ordered a custom set of wheels once and the manufacturer "forgot" to cut them for caliper clearance. I had them send me a diagram of the clearance cut from which I made a go/no go gauge, then cut them in the lathe myself. I also got from them a letter stating that all warranties and liabilities were in place, even though I did the machining.

[datsunfreak]

2 hours ago, Stoffregen Motorsports said:

I also got from them a letter stating that all warranties and liabilities were in place, even though I did the machining.

 

That was nice 👍

[datsunfreak]

Looks like I need maybe a 5mm spacer for "comfort". Caliper is into the spokes about 1-2mm. 

 

[datsunfreak]

A friend of mine offered to sell me his seats since he was changing them out for something new, so my current Recaros will probably end up in the Dajiban. 

 

These new ones are the Sparco SPX. I thought since I will be running a suede Sparco wheel, and Sparco 6pt harnesses, why not get some seats to "match"?  😁

 

 

 

And yes, they are made of real carbon fiber...  🤘

 

 

 

 

I know this is dumb at this juncture, but the deal was WAY too good to pass up. 👌

Edited September 29, 2023 by datsunfreak

[datsunfreak]

Haven't gotten any serious work done yet, but I think I will soon. Did pick up another piece of the puzzle today...

 

 

 

It is a manual steering rack from a 2010 Cobalt. This is what we used on Tim's 1200 project as the width between the inner tie rods is the same as the 240Z rack, so geometry stays within spec.

 

A few nice benefits are it's aluminum (fair bit lighter than the stock steel rack), and it has a slightly quicker ratio. The ratio of the 240Z rack is 17.8:1 and the Cobalt is 16.6:1. It also has more turns lock-to-lock (3.6 versus 2.7), so this should mean there's potential for a lot more more steering angle. 👍

Edited March 7, 2024 by datsunfreak

[datsunfreak]

12 minutes ago, datsunfreak said:

it has a slightly quicker ratio. The ratio of the 240Z rack is 17.8:1 and the Cobalt is 16.6:1. 

 

Also worth noting, the JDM 240Z steering rack is supposedly 15.5:1 ratio, so I don't think I'm going too far in quickening it a bit. Conventional wisdom is that since the S30 was not going to have power steering, they used a slower rack in USDM cars to make steering effort feel lighter, like the car had assisted steering. 

 

Gotta love the Japanese. Always dumbing stuff down for us fat, lazy Americans...  😋

[shlammed]

what is the width of the spacing of the inner joint on the cobalt rack?

 

[datsunfreak]

On 3/4/2024 at 9:19 AM, shlammed said:

what is the width of the spacing of the inner joint on the cobalt rack?

 

 

I don't recall the exact numbers, but I know it is at most 3-4mm wider than the stock rack. Which was close enough for my needs. 

 

This site claims 610mm for the 240Z, so I would say 612-615mm (roughly 24.0-24.2")?

 

 

 

The faster ratio, and the design of the inner tie rod, on the Cobalt rack makes for more turns lock-to-lock. 

 

 

 

 

Edited March 7, 2024 by datsunfreak

[datsunfreak]

On 3/4/2024 at 9:19 AM, shlammed said:

what is the width of the spacing of the inner joint on the cobalt rack?

 

 

I am curious what made you ask? Considering it for a 510? 

[datzenmike]

It may have more turns lock to lock but the hubs probably have stops that won't let you use all of it.

[datsunfreak]

2 hours ago, datzenmike said:

It may have more turns lock to lock but the hubs probably have stops that won't let you use all of it.

 

240Zs do not have those "stop bolts" you see on most Datsuns. You typically only see those on cars with recirculating ball steering boxes, not rack and pinions.  Assuming that's what you meant. If not, maybe? We shall see...  😁

 

What I did find odd is that FWD cars are notorious for having a crappier turning circle than their RWD counterparts, owing to limitations on how far you can rotate the CV joints "out of alignment". So you'd think the 240Z would have more steering angle, but it doesn't due to (mostly) limitations in the rack itself.  

Edited March 15, 2024 by datsunfreak

[iceman510]

Another FWD limitation comes from the overall width of the transverse FWD engine/trans combo dimensions.  At my former job we had the same vehicle with different turning circles between AT and MT versions due to the much larger packaging space required for the AT box.   Thus different steering racks too.  Talk about build complexity.

[datsunfreak]

After thinking about this way too mcuh, I'm not 100% sure if steering angle will increase or not. I only know two things. The quicker ratio will be better (IMO), and I can measure the actual difference in angle change once I fab the rack mount. 

 

Even if there is no appreciable change in maximum steering angle, this is the rack I am using, so fuck it. 😁

[shlammed]

8 hours ago, datsunfreak said:

 

I am curious what made you ask? Considering it for a 510? 

Im considering making something like jbc offered. 
 

cobalt racks are a lot more available. 

[datsunfreak]

On 3/15/2024 at 4:11 PM, shlammed said:

cobalt racks are a lot more available. 

 

Indeed. You can even buy them new for a nominal sum. 👍

[datsunfreak]

On 2/3/2023 at 9:49 AM, Stoffregen Motorsports said:

Swapping a 4 banger into the Z car is a great idea. I've driven them and they handle awesome, but the wow factor of a fire breathing V8 can't be beat.

 

With the KA seller dragging his feet on removing the engine from his car, and the fact that there's a 302 at my shop staring at me every time I walk past it, the tide may be changing... 😁

 

Once we get Tim's engine swapped out in his van (hopefully within a month), I am going to repo my engine stand, chuck the 302 on it, and see how she goes. Obvious first step is to crack it open and see if it's any good. It will probably need some head work (or these) and the bottom end refreshed at a minimum. Then I need to find an appropriate transmisison, probably a T5 since I know it fits in the car well and the M5R2 doesn't. 

 

I got to thinking about cost/complexity/power output, and I think a 302 V8 is a better call. Obviously less complex, easier to swap in, and more power per dollar than the KA24DET. 

 

And you can't beat the sound...

[Icehouse]

No power steering?  I'm a huge fan of hydraulic power steering.  It feels the best.  Still feels mechanical unlike electric steering.  If you do the V8 your going to need all the help you can get turning the steering wheel.  My Z with the SR is annoying, autoxing almost impossible to be fast.  Josh with the purple 510 build did a Z with some sort of classic car rack you can buy new for cheap that's power.  I'm going to swap one in my rig.   for a manual rack it's hard to beat the Escort rack, many speeds and cheap.  

[datsunfreak]

16 hours ago, Icehouse said:

No power steering?  I'm a huge fan of hydraulic power steering.  It feels the best.  Still feels mechanical unlike electric steering. 

 

It is not in the current plan, but that doesn't mean it won't be down the road. 😄

 

16 hours ago, Icehouse said:

Josh with the purple 510 build did a Z with some sort of classic car rack you can buy new for cheap that's power.  I'm going to swap one in my rig.  

 

If you find out which one it is, please let me know.  👍

 

16 hours ago, Icehouse said:

for a manual rack it's hard to beat the Escort rack, many speeds and cheap.  

 

I am using the Chevy Cobalt rack because it's a good fit, and super cheap. Also, I needed a rear steer rack that can easily be flipped over to front steer since I want to convert the car to right hand drive, and this one fits that bill.

 

And it helps that we already did this swap once. My friend Tim's 1200 has 240Z front suspension and a Cobalt rack. We flipped his crossmember around to make it rear steer, and just made custom T/C rods that go forward instead of rearward. 

 

I was concerned that flipping a power hydraulic rack may be problematic?  But I suppose if you could convert it to banjo fittings (or AN), it may not be an issue?

[Icehouse]

hmm I never thought about flipping a hydraulic rack and the fittings being an issue.  Maybe?  If you do a 4 cylinder I doubt it.  My rack could be moved up with zero issue since there is no engine above it.  

[datsunfreak]

16 hours ago, Icehouse said:

 If you do a 4 cylinder I doubt it.  My rack could be moved up with zero issue since there is no engine above it.  

 

The only thing I have set in stone is it will either be a 4 or a V8, so definitely nothing above the rack. 

 

It was more since a lot of racks are designed to angle the hoses "back", that flipping it would angle them "forward". But it really depends on the rack. If it's something from a FWD application like a Cobalt, the hoses should go straight up. 

[datsunfreak]

On 10/18/2024 at 10:43 AM, datsunfreak said:

With the KA seller dragging his feet on removing the engine from his car, and the fact that there's a 302 at my shop... Then I need to find an appropriate transmisison, probably a T5 since I know it fits in the car well and the M5R2 doesn't. 

 

This is not working as well as I had hoped...

 

On 10/18/2024 at 10:43 AM, datsunfreak said:

I got to thinking about cost/complexity/power output, and I think a 302 V8 is a better call. Obviously less complex, easier to swap in, and more power per dollar than the KA24DET. 

 

I am almost completely waffled back over to the KA24DET. I think if I splash out on a custom harness (like this), and maybe a custom engine mount (like this), the swap should be pretty straightforward. That just leaves plumbing to figure out, which was about the same amount of work for either engine, so...

 

I think the weight savings (likely 150+ pounds), and better transmission options, eventually won out. That, and being able to use the stock driveshaft (instead of custom), my cable speedo (instead of a $300 GPS speedo), the stock hydraulic clutch gubbins (instead of custom), makes this the right call.

 

And this may just be what Tim calls a "head wash". We shall see. 😁 

[datsunfreak]

On 2/17/2023 at 7:44 AM, datsunfreak said:

Spoke with the  shop my friend recommended this week. They said they can blast/prime it for a price I can live with, so I am hopeful that will be happening soonish. Would like to get started on actually building stuff for the car by summer. 👍

 

Well, somehow that took two years... 🙃

 

Finally got the car moved to my shop today, and strapped onto a body dolly. So, hopefully I can get it to the blast guy in the next few weeks... 🙄

 

Also, anyone from near Gramps Ass know a guy called Tom Cruse?  😄

 

[datsunfreak]

Picked up a crusty 240Z front suspension this week...

 

 

 

Got it all broken down to see about fitting the new rack to the crossmember. As it happens, the input shaft fouls the motor mount standoff...

 

 

 

Fortunately, I do not need those...  😁

 

 

 

After some head-scratchin', we figured it would be simpler to make a second frame member to mount the rack. So we are just going to shave everything off the stock crossmember, and make something better to fit the rack to the car... 👌

 

I could probably also just make a whole new crossmember (and might), but we aren't quite there yet... 😅