Thought I'd start this up to try and get more posts happening to get a handle on this Moderation setup.

Two related questions but with different answers. Will throw some more in later.

1. Explain why the 253/4.2 high comp was given an RPO code despite the fact it was not required to have one for HT-HQ prior to LH Torana? L33 exists starting in HT literature but L32 was never applied in any order form or similar literature as it was always the standard engine in all V8 models except for Brougham/Deville and GTS350. For the same reason the 161 never had an RPO code for HK-HG and 173 never had an RPO code for HQ.

2. Following from the above, explain why the LD1 code existed for both 161HC and 173HC engines? They were both standard HK-HQ engines Again the low comp versions were optional engines for all of HK-HQ so you could always option L21 and it exists in PTC lists etc. A big clue exists in the RPO itself in relation to the others around it:

L20 186HC and 202HC
L21 161LC and 173LC
L22 130HC
L23 186LC and 202LC

L30 307 and later HQ 350
L31 308
L32 253HC
L33 253LC
L34 327

LD1???

There are definite answers to the above two questions.

As for L14, not sure. L66 for 186S is another seemingly random code that doesn’t really fit. I have been digging to see if GMH would have kept L66 for the 202S in HQ, it would have got a code like 186S did as it was to be optional outside of GTS.

Looks like no takers?

Here is the answer to question 1. Pictures tell the story, remember HK only had one model per body/lux level. Whereas as HT had two models per body/lux level - example Belmont sedan 80169 and V8 Belmont sedan 80269. So with 253 planned for release with HK coupes, the 253 was an optional engine whereas in HT-HQ it was always the standard engine in most V8 models. So it needed an RPO code and L32 was given. Otherwise it would never have been given an RPO code until LH Torana. An example of no code is I believe the LC GTR 2600S and 2850S.





You will also notice a few things there in the PTC's that never did happen. Like M22 behind V8. And the planned use of a 6cyl grey iron banjo centre behind a V8 - that never happened either. The V8 banjos were always the stronger nodular 2.78 and 3.08. 3.08 became the standard 253/4.2 manual rear axle ratio for a Holden until HX (but was a Salisbury for HQ and HJ). And 2.78 became the 253 auto ratio until GMH retired the 2.78 Salisbury around the end of HJ.

Edited by user Friday, 5 December 2025 7:57:38 AM(UTC)  | Reason: Not specified

Yes Terry, option 636. Only available as RHD, Export only and manual only. Only available on 215, 225, 219 and 229. There is nothing in the HR Eng Tech Specs that spells out its engine number prefix.



Here is where it was added to the Eng Tech Specs:



There was no need to give RPO codes for stuff that was standard, I know its an extreme example but there was no RPO code as far as I know for front drum brakes - you couldn't order it.

Edited by user Friday, 5 December 2025 3:52:10 PM(UTC)  | Reason: Not specified

Byron, why wouldn't the 130ci in HJ be QA, because it was seen in HQ & the PO number would've applied in HQ.

On the subject of Chev 6-cyls in HR to AJ in Sth Africa. Were these engines sourced from the USA, or were they built in Sth Africa.

The reason I ask is because in SA they had a very strict local content system based on weight. Things like brake drums, rear axle assemblies gearboxes etc. were built locally to satisfy these rules.

In HR the imported Premier had a Holden 186 with 126 bhp, while the locally built Special had the much heavier 194ci Chev engine with only 120 bhp.

Dr Terry.

What about the 194ci 6-cyl Chev in the HR series. Was it made in Sth Africa or was it a US import ?

Dr Terry

I found this on a site, Copied & Pasted:

South Africa's local-content scheme, the Motor Industry Development Plan, was implemented in stages beginning in 1963. Local-content percentage was based on vehicle mass, not value, so most manufacturers opted to make engines locally. Around 1965, GM opened its Aloes engine plant near Port Elizabeth to make engines in order to meet local content. Two basic engines were made locally: the Vauxhall Viva unit, fitted to both Viva and Kadett, and the permutations of the American "Chevy II" unit, which could be easily made in both four- and six-cylinder guises, and fitted to everything from the Opel Rekord up to the Chevrolet Chevelle. Locally-made engines gradually replaced the imported engines in CKD packs.

Holden was introduced to South Africa in 1960 to give the Pontiac-Opel dealers a bigger, six-cylinder saloon that was cheaper and more rugged than the Opel Kapitan. South African-assembled Holdens began using the locally-made engines during the HR's run, though one of my data books suggests that all HR Premiers used Holden engines. There were even Holdens with the 2,5-litre Chevy four-cylinder, but they sold poorly and were quickly dropped. HK-HT-HG Kingswoods and Premiers used 3200, 3800, and 4100 versions of the Chevy engine. The Belmont Utility, however, was a commercial vehicle, subject to only nominal local-content requirements, and used the 3,3-litre Holden engine. All South African Monaros were Holden 308s.

Many Australians hold the belief that the Holden-bodied South African Chevrolets replaced local Holdens but that generally wasn't the case. GM South Africa had two different sales channels at that time, much like the set-up in Canada, with one channel selling Chevrolet and Vauxhall, the other selling Pontiac and Opel. 1967 looked like this:

1. Chevrolet Caprice, Chevrolet Chevelle, Chevrolet Chevy II, Vauxhall Viscount, Vauxhall Cresta, Vauxhall Victor, Vauxhall Viva
2. Pontiac Parisienne, Acadian Beaumont, Acadian Canso, Holden Premier, Holden Special, Opel Rekord, Opel Kadett

Rationalisation was in short order, and the bigger Vauxhalls and the Canadian models were gone by late 1969, leaving just the Viva, Kadett, Ranger/Rekord, and Chevrolet/Holden. The lineups were more or less tit-for-tat, but Chevrolet got the long-boot Constantia while Holden got the Monaro GTS! Nevertheless, GM was losing market share and it was decided to merge all the dealers and concentrate on one brand. So in early 1971, the remaining Rekords and Holdens were dismissed and all GM dealers became "Chevrolet" outlets, though the Kadett continued until 1974 and the low-volume Manta was always on offer as an Opel. So, the Holden Ute and Monaro then became, respectively, the Chevrolet El Camino and Chevrolet SS Coupe.

Trivia: GMSA did not produce the bodies for the local Holden-derived Chevrolets. Holden pressed the Chevrolet-style front panels, grilles, and bumpers and included them in CKD kits. The discontinuation of the Holden brand obviated the need for separate Chevrolet and Holden styling, which is why the South African HQs and HJs (known locally as AQ and AJ!) used Holden's front styling, but with Chevrolet-style grille patterns.