Quote:

you still haven't answered the question of what ratio it is that you are after.
Re: the roadstar diff, they are talking about substituting the entire rear axle assembly for the 120Y one. The ute ratio is 4.11:1 as stirlingmac said, but others are more readily available than for the 120Y (3.9:1 H145).
Also where's the 195hp coming from? I thought that your engine was still at the reconditioners? And you are after an A14GX head which I assume means you're running an A-series, in which case it must be a pretty special one to be poking out that sort of power?http://www.datsun.co.nz/phpBB/viewtopic.php?t=2460

Ihave used 510 wagon diff. wide selection of ratios

Quote:Point of order
The B210 [120Y] used the H150 diff in 3.9 to 1 ratio.
Only 1000's & 1200's used the H145 size as far as I can tell, although the H150 will bolt into the H145 housing using a spacer.[?] [this issue of a spacer is currently under debate]
The H150 is available in 3.7 to 1 ratio as well as 3.54 to 1.
Quote:What more could there be? The rear end size & ratios were tailored for the car, complete with it's stock A12, A13 or A14 engine [depending on which country you bought it in] so, what else could a new car buyer want? The larger & heavier H165 series of rear ends would have been un-necessary overkill, it would have cost more, thereby eroding a sales advantage, & it would degrade ride quality, something that motoring writers would pick up on very quickly, to the detriment of sales.
I guess that's why there were not more diff options.

1974 B210 used the H145. I don't know when Japan A12 models switch to H150, but in USA it happened when they moved to A14 engines (1975). See the Tech Section diff article for more information and ideas.

If your SSS is using taller tires than stock or you have an overdrive 5-speed, a 4.11 gear would be just the ticket. For most B210s I'd I'd suggest a 3.9, but with 195HP naturally aspirated it should rev high and a 4.11 or even higher is called for ...

When I wrote diff I mean't the whole rear end assembly. Your 120y NZ spec when new had a H145 rear axle assembly. It probably still does though it would pay to check. The later 1200 utes had larger and stronger H165 assemblies and now reasonably rare. The ute assembly will fit onto your leaf springs but you may have to modify the bottom u bolt plates/shock mounts. the easiest way to ID the diff you have is to look at how the diff centre is held in the housing, if it has nuts it's a 145 and if it has bolts it's a 165. As for the 150 spacer debate I thought that was settled ages back. Almost all the 150s I have measured required the 2 mm spacer ,but the 150 centre in my coupe has been manufactured to the 145 dimensions ???Unusual for Nissan to cock up but it worked out OK for me.

Cheers for that.
now will have to find the Complete Diff
Mod's don't sound to much,

Apreciate your assisance

Quote:Well you got me there.
My factory B210 manual [April '76] refers only to the H150 diff & I foolishly assumed that this is the way it was all over the world. For whatever reason, it looks like Aussie models got the H150 from day one while other markets continued to use the H145 for a while.
The Borg Warner rear axle assembly was introduced in locally assembled models from July '76 & the factory covers it with a separate workshop manual suplement.

The date of using the H165 in NZ utes is different from here too. We got the H165 from at least '74 & I have seen one of the earlier utes ['70 to '73] with an H165 also, but I never checked on the one under my '73 ute when I had it back in the late 80's so I don't know when they were first used here.

One of our club members in Sydney has an H150 diff in his 1200 [H145 axle housing] without a spacer & says that it gives no trouble at all, so this is an interesting subject. Maybe these two diffs were intended to be used in H145 axle housings in the first place.
My own H150 is from a late B310 so it will probably need the spacer ring.

I tend to agree with you on the diff issue. In a standard open diff I reckon the deflection in the side gear divided by the length of the axle is not enough to cause problems. With the fitting of a LSD the tolerances tighten up on the side gears and maybe thats where problems occur. As for the ute diffs my Kiwi parts book lists both 145s and 165s. From 78 on the 165 appeared in most utes. NZ assembled the 1200 sedans and 120ys but imported the utes. We were at the mercy of the factory I guess and took what ever they sent !!!

Quote:It looks like you think you will be geting 195hp from an A12 with an A14 [oval port] head with twin DellOrto's. Lotsa luck. A nominal output of 162.5hp per liter, normally aspirated, in a street vehicle is really a bit optomistic. There are some pretty hot n.a. A15's out there that will never see numbers anywhere near that.

You also write about the DellOrto's won't fit the A14 head. These would be the original carbs that came with the SSS model I guess & it's the 'manifold' that won't fit, not the carbs. By using an aftermarket manifold designed for twin Webers on an A14/15 head you would be good to go as the DellOrto's share the same carb-to- manifold bolt pattern.
The A14 head has larger valves & larger [oval shaped] inlet ports. They also use a different manifold bolt pattern.

To keep things under control, consider this option.
In order to retain the value of your relatively rare SSS model, perhaps you could simply spend some cash on a modest porting job on your original head. Fit the A15 sized valves & you can keep your original manifold & carbs. The power will be a bit less, but then you will retain the value of your car & at a genuine 195hp, [normally aspirated] that engine would be pretty much undriveable on the street anyway. OK, even race engines aren't that good, so it would be almost impossible to drive in any kind of traffic.
With a lower [& more realistic] power output you can lower your costs with serious rear end &/ or gearbox upgrades &
reap the double benefits of reduced costs & increased driveability. This means a more fun car to drive.

Rare models command top price when in original condition with all the original [rare] parts.
You will still have a top performing car that everyone will envy.
Have a think about it.