1970 240Z Works Rally - the road to restoration

[HS30-H]

On 12/25/2022 at 2:49 PM, kats said:

Hi, I looked at magazines in my room and I couldn’t find any clear pictures of the diff oil cooler installed on other Works cars.

5 hours ago, xs10shl said:

The steel plate on 8D-433 shades our view of the differential area. Without a clearer photo, it would be hard to tell what is in the cavity between the tank and the differential, where the diff cooler is situated on my car.

I was told that the diff cooler setup on '8D-433' (the '71 Safari winner) was removed when the car went back to Japan and began to be used as a display exhibit to celebrate the Safari win at shows and regional dealerships. Probably part of an effort to make the car a little more practical (and less smelly...) and for sure some effort was made to tidy the car up a little at that time. Back in Japan the car became visibly more complete than when it finished the Safari.

Then, a few years ago, Nissan's team of volunteer restorers at Atsugi 'refreshed' the car once again as part of a program intended to make the car 'safer' and more presentable for public display (liability insurance concerns part of the deal) and - in my opinion anyway - they got a bit too close to throwing the baby out with the bath water. For example, they re-upholstered the seats (in the wrong shade of fabric, grrrrr...) and touched up paintwork that didn't need touching up. They even replaced the rear license plate with a new one (grrrrr...). They had done the same with the '72 Monte Carlo 3rd place finisher some years earlier, with similar baby-down-the-plug-hole results.

Its hard to photograph the diff cooler in situ unless you can get the car on a ramp or lift, but - I think - in the '71 Safari winner's case it is no longer there to be photographed.  

[xs10shl]

A little more on the R180 4-pinion LSD: mine arrived disassembled with the car in 2014.  The mounted ring and pinion is 39:8 (from my reading), which amounts to a 4.88.  I don't know yet what ratios are in the gearbox, but my sense is that I'll probably want to change the diff ratio for modern autocross use.  The rear plate makes use of existing threaded holes for inlet/outlet for the diff cooler. 

My understanding is that the Ring/Pinion set is swappable with other early non-LSD R180 rings (but not later ones), so that part will hopefully be straightforward.  As to the LSD internals: I've yet to assess the condition of the clutch packs, so I may need to swap out the LSD with something else in the interim, until I've got the parts I need to complete the overhaul.  For most uses, I doubt I'll notice the difference.

 

 

Edited January 8, 2023 by xs10shl

[HS30-H]

I'd like to encourage you to rebuild the diff with its 4.8 ratio intact. If you want to use the car for some events using a different ratio, I think it would be better to have another diff on hand for that.

The tyre diameter on the car - if using something close to the period Works Dunlops - will mitigate the ratio. I don't think it will be as drastic as you might imagine. And even if it does seem a little frantic, that's the nature of a Works '71 Monte car...    

The Works team used anything up to 5.1 ratio in period, so with a 4.8 you're not even at 11 on your Marshall amp. 

[Patcon]

Also autocross tends to benefit from lower ratios because it's not about top speed but about acceleration. Which is easier and quicker with the lower gear advantage

[Patcon]

Another thought, I don't know what the plates look like in your diff but some of the guys at HybridZ had CLSD plates torched out for the R200's. I don't know if they are interchangeable or if their source would be helpful. Just, another possible source...

[xs10shl]

A few of the discoveries during disassembly- strengthened gearshift mount (with stock mount for comparison), shortened steering arms (longer arm on left is stock), and rear left-side splash panel - just some of the little details which escaped us earlier that we're now noticing. These are perhaps easily overlooked features, but for me, its just interesting to see the attention to detail.  All these mods serve a specific purpose.

 

 

Edited January 27, 2023 by xs10shl

[xs10shl]

Today I turned my attention to the alternator, to see what I could learn about it, and share some of my early findings.  Works cars had up-rated alternators with on-board voltage regulators, which was a departure from the S30 production cars.  I've attached a few close-up photos to show how it looks in the car, and from the bench.  I've also included a photo of the alternator used in the 1971 Monte Carlo - to my eye, they look similar enough to be considered equivalent, although I don't see any part numbers on the alternator, so there is no real way to be 100% certain.

Without having any markings on it that I could see, I elected to disassemble it in anticipation of getting it rebuilt and ready for use.   I didn't get very far before I had to quit for the day, but at least I was able to disassemble enough of it to get a picture of the markings on the voltage regulator - it's a Hitachi TR1Z-06. Based on a 1971 document I've downloaded from Hitachi's site, a version of this IC-based alternator was used in the Nissan President and Cedric, and it came in 40, 50, and 60A models.  I'll need to bench test this one to determine its actual output. 

It appears that stock units did not have the protective black rear cover (see picture of a stock example). It was likely added by the Works team to provide additional protection to the voltage regulator.

[HS30-H]

7 hours ago, xs10shl said:

I've also included a photo of the alternator used in the 1971 Monte Carlo - to my eye, they look similar enough to be considered equivalent, although I don't see any part numbers on the alternator, so there is no real way to be 100% certain.

I have a Works 240Z rally car alternator. It is a Hitachi L-X503. I was told by several people in Japan that this was a heavy duty type usually fitted to various trucks of the period. 

Works rally modification included adding a splash shield to protect it from ingesting road debris. This was spotwelded to the fan blades.

Here's a period photo of a Works car engine bay where the same or similar Hitachi part number is visible:

 

[HS30-H]

Here's mine:

[xs10shl]

Thank you @HS30-H -  I used your pictures to locate some incredibly faint imprints of the Alternator: L-X503 12V 00806.  I'm supposing the difference in the last number indicates that these are a run of numbered units? 

[HS30-H]

11 hours ago, xs10shl said:

I'm supposing the difference in the last number indicates that these are a run of numbered units? 

Seems logical. Our numbers are very close too.

[xs10shl]

I've got a small vapor honing booth at my shop, which is good enough to clean things like windshield wiper arms and carburetor lids.  For the big stuff, I tried out a new local service called Spray Technology in Santa Clara CA, who had heavy-duty equipment, and I was not disappointed.  Everything looks better-than-new.

 

Edited March 15, 2023 by xs10shl