I don't know if the rest of you group differential with rear suspension or transmission. I'm going by the logic that it has gears and oil, like the transmission...

The question is:
"Do all of the Belletts use the same rear differential carrier?"
or
"Will the same rear differential carrier housing fit all Belletts?"

I realize there are non-LSD differentials, and the GTR had a LSD. I will assume the GTR LSD can be fit to at least the standard GT differential housing/rear end/pumpkin. Is this true of most or all of the other Belletts (Sedans, Wagons, etc.)? And all years?

As a side note, can the ring and pinion gear sets be swapped through all years and models as well?

ok. here goes...

all IRS Bellett sedans and GT's (including GT-R's) used the same diff housing, irrespective of the year model.
99% of them had a 3.73:1 ratio, and a 4.11:1 was an option.
i've heard rumors that the automatic trans sedans had the 4.11 as standard, but i've yet to see an auto have anything other than a 3.73...
i know that the Florian's had 4.11 standard. the crown wheel and pinion are interchangable with a Bellett, as they just used Bellett gears in a different carrier.
the GT-R LSD was in a standard Bellett IRS housing, so it's interchanable as well.

the Bellett B (with the squared of rear end) had a live axle and leaf springs, so the diff carrier is not the same. as for the gears inside it... i wouldn't have a clue, but a guess would say that it's highly possible that are interchangable with the IRS Bellett, as the Florian was live axle as well and used the same gears as the IRS Bellett, and they were all built at the same time.

the Wasp and Express Wagon were all live axle as well, so the carrier is another "no go" here too.
i've been told that the gears can be put into a Bellett carrier, but don't quote me on this or go ahead and try it without checking first, as i've never tried it myself and can't confirm if this is true or not.
the standard Wasp ratio was 4:56.1, and an option was 5.11:1, but i've never seen a 5.11.

hope this answers your questions.

Which of the Bellett Sedans had the independent rear suspension? Was this a model year change, or determined by different trim levels within the same year or years?

I have no idea why this occurred, but all Belletts had IRS, right from the word go in 1964.

However in the last 60's or 1970, Isuzu brought out the Bellett B which appeared concurrently with the original series.

The Bellett B had headlights from a 1300 (like the PR10 that is in the USA featured elsewhere on the site) and also had different rear sheetmetal; a larger, squared-off boot lid and quarters (think Datsun 1600) and a less chopped rear wheelarch (more flare, slightly rounder).

Weirdest of all was the usage of the a live axle and leaf springs! Especially after every single Bellett brochure gong-beats about how great the IRS is (when you're not sideways with the inside wheel tucking under, about to die).

I have a brochure for the Bellett B and it was going to be the next one I scan so hopefully I'll get time to do that tonight.

As it's in Japanese, I still have no idea why such a car was created. PR91 Brett believes it may have been for a fleet or taxi market where a larger carry area and the extra load carrying ability of leaf springs may have been important, but I think the car was available in a Deluxe form (don't quote me on this yet) which is weird as most taxis are not deluxe items in any given market. Normally they're the cheap-o cars that get killed over the course of a million k's (or miles)!

So yeah, if the Bellett you're scoping has the familiar round bum, it's IRS, if it's looks like someone's grafted a Datsun 1600 (aka Bluebird, P510) rear end onto it OR it's a wagon or a utility/pick up, it's solid.

Cheers.

Dave

to put it all simply...
every Bellett you see on here is IRS.
the live axle Bellett B was rare in the day, and I don't know of anywhere else but Japan that they were available, so it's an impossible thing to find now.

perhaps the live axle was a pre cursor to the t series gemini?

I would have thought that.... but it turns out not to be true.

With the updated rear sheet metal and the (presumably cheaper) live rear end, it would figure that they came out towards the end of the Bellett's run.... however I've found a Bellett B brochure and the theme of the brochure (LSD Magical Mystery Tour) and the interior is clearly 1967-vintage stuff. Check out the brochure that I've posted in the brochure section (give me a minute; I'm doing it next).

So the Bellett B remains a mystery; it has a slightly longer wheelbase, wider rear track and what appears to be an exceptionally larger boot. And is just a deranged, rare and beautiful mystery.

We have had 6 different final gear ratios for GT:s here in Finland. 3,727 (number of teeth 41/11), 3,778 (34/9), 4,100 (41/10) < that is also in Florians, 4,111 (37/9), 4,300 (43/10) and 4,625 (37/8). Those all are also in the homologation forms of Belletts and they vary in different GT models. And of course you can use all these with the limited slip diff. There is also very many Bellett gearboxes with differet ratios to suit different final gear ratios for rally or track.

...the standard Wasp ratio was 4:56.1, and an option was 5.11:1 ...isn`t possible found this 5,11:1 differential ????? it is perfekt, in my historic rally GT projekt.... ...

Was the wasp IRS? Being a truck I automatically assumed it had a live axle.. keep in mind I've never seen one in real life!

The Wasp has a solid rear axle. No IRS there

...but, i think , att indoor parts are same... ???

I think you are right. From what has been said and what I've read the internals to the diff's are interchangeable.

R.

Wasp diff banjos are interchangeable with LUV/KB & Jackaroo/Rodeo until; the 4ZE1 (including LSDs).
Also with Florian (4.1) and Piazza incl LSD (3.9).
The Bellett-B's were mainly used for taxis.

I am not sure if Australia got the non-turbo 2 liter Piazza. The Piazza with the G200 engines did not have the same differential as the Piazza with the 4ZC1 and 4ZD1 engines. The early non-turbo shares only the body and trim with the turbo and later non-turbo models.

The Piazza with the G200 engines share the same differential as the early 80's Gemini RWD and Opels.

It is surprising to see the differential skip over the middle like that with the late 60's and early 70's cars using the same differential as the late 80's and early 90's cars. I can't find anything else that carried over, not even the wheel bolt pattern.

Yep - the Kiwis have the torsion tube rear; the Aussies have the link rear (Piazzas).
And Aussie Gemini's ain't Isuzu (Salisbury & BorgWarner diffs).

As to skipping - I'd like to know why the earlier G200(W) Piazzas have the I-TEC EFI, but the later 1986 Aussie 4ZC1-t turbo reverted to ECGI style with mechanical distributor (which then feeds the ECU for knock compensation). GMH did order the then superseded Piazza chassis - and stuff the suspension - but did they do more? (Was full electronic too much for the Aussies?)

The three link is the G200, which shares the diff with the RWD Gemini.
The five link is the 4Z engine and shares the diff with some of the trucks.
My access to truck information is limited, but the open diff for the five link matches the 1984-1990 2WD Pickup, Amigo, and Trooper II but only those with the 2.0 or 2.3 liter engine. The 2.6 liter 4ZE1 models show a different diff, as do the multiple 4WD listings. The 2.6 liter truck diff does not show to be the same exact part as the 2.0/2.3 truck or the Piazza five link.
It is possible that some of these are interchangeable or share the same exterior dimensions, but they do not indicate limited slip, while showing a cost of 3-5 times more.

The Piazza five link was available in open or limited slip, and those two were interchangeable, so they do have the same dimensions.

From the earlier post, the Bellett and Florian share the differential with the Piazza with the five link rear suspension, the turbo model, and the 1984-1990 2.0 and 2.3 liter 2WD trucks.
But you comment on these same differentials being Salisbury or BorgWarner. Are you saying that the Bellett and Florian had Salisbury or BorgWarner differentials?



My understanding is that Holden was required to have a certain percentage of Australian content, and the cars were either shipped without an engine control system, or the wiring harness and sensors were stripped and replaced upon arrival.
I remember something also about Australia not having 87 octane unleaded fuel at that time, which might have had something to do with it.
All the US cars got Bosch/Hitachi hot wire fuel injection, no trap door MAF sensors.
These were the first cars with a computer controlled turbocharger, at least the US and Japanese versions. I don't know if Holden stripped out the turbo control computer too.

Not sure where that came from. The Bellett & Florian crown & pinion are interchangeable, but not the diffs. AFAICR, the Bellett is on its own.
The Florian, Wasp and (eg) Rodeo/Jackaroo diffs (until 4ZE1) are interchangeable - ie, swap complete banjos (not individual parts). (There may be minor differences like longer Wasp front flange etc.)

All the above are Isuzu (Jap) diffs.


Re the ITEC to ECGI - it's still all Jap so there is no local content difference.
Fuel wouldn't matter as that's a remapping issue, and it's easier to remap a chip than remap springs, weights & diaphragms (as well as limit the advance for the turbo).
If it were an "analog" ZZ/R type ECU (eg, PF60E), I might understand it, but the G200 ECUs were digital (ie, uPC controlled).
Puzzling isn't it?

The ITEC ECU has a PROM chip. It is not flash programmed. To reprogram it, the ECU must be removed, the case opened, the chip removed from the circuit board, and a different chip reinstalled in its place. These are the type of control systems that brought about the term of "chipping" a car with a higher performance PROM chip. These are also the control systems that anyone with a dyno could prove how much a waste of money it is to "chip" a car, because they usually ran worse with the higher performance chip than with the original. If the aftermarket had such a dismal success record, maybe the manufacturer and distributor knew any effort to modify the existing system would be an equal failure and decided to change the system completely.

I'm not sure what your point is.
Are you saying that the Piazza etc ECU was never remapped, or that they would rather do a new mechanical run than another mapping?
Whether it is mask level ROM etc won't matter - a normal mask run is 1,000 units, but this does not mean it's not economical for smaller runs (eg, 500 for racing - just don't use the surplus).

I reckon the aftemarkets have been a failure because of their primitiveness. I've had copious "discussions" with so called experienced/experts about why ECUs cannot self learn, or why they need a (cam referenced) CAS for sequential etc, only to find out that OEMs have been self learning since the late 1980s. Some aftermarket units are still 8 bit! (Ca: 1986 I designed an all-electronic ignition system timed off the flywheel based on 6511 or 68HC11 etc. It was self learning. It was easy to extend that to EFI some 20 years later when the above "discussions" occurred, but then it would have been a 32-bit MPU with speaker etc (all for $2!).