well ....a bit confused here , Export, made in Aussy was called Chevrolet 350 ( an hq Statesman with different body mouldings & 350 motor) went to NZ & other markets , but not South Africa ,which had its own locally assembled version , defiantly no 454 . Not sure why the Chevrolet 350 was not marketed in Aussy , but you could still get the 350 in Statesman & Monaro.Hope this helps , Mark.

Thank you very much guys. Now it it's falling into place. Seems the original article I read was a tad liberal with the truth. I've seen 3 or 4 of these HQ statesman Chevs back in the day when they were released (I'm 60) and I never saw Cadillac mirrors. The 454 option was printed in the article I read, maybe it was considered but not done. Reporters don't like letting the truth get in the way of a good story! As for the lack of performance in what one of them stated as being a "Holden 350" rather than a Chev, also seems to have been stretching the truth. So what you guys are saying is that it was merely the Carb and dizzy required for a quick conversion to Aussie fuel and emission requirement variation. Thank you very much for insight. I know a lot of similar issues that happened in Chrysler Australia but I have precious little knowledge of Ford or GMH so thanks, it is very much appreciated. By the way My Daily driver is a 2010 6ltr Caprice, my wife has a 2008 G6 and I love them both but my real passion is my '69 440 Dodge Charger R/T (clone) It was a base model 318 when I bought it.

The exports weren't called a Statesman, just Chevrolet 350. It is possible that when GM designed the LWB sedan before it became the HQ that they considered a 454 but not in Australia.

The performance probably would have been better than a similar sized US vehicle with the same L48 engine due to more available spark advance and higher Octane fuel. A HQ is similar in size to a 1970-1971 Camaro or maybe Chevelle. The carby tune will be the same, just with AIR changes on the US carbs (which I think is a sealed fuel bowl and non adjustable idle screws). I don't think it was a quick conversion, just needed more advance. The HQ distributor is 1111500 (same specs as 1111150), has 4deg initial and 26-30deg total at 4200rpm. The US 1971-2 L48 manual (1112044) is 4deg initial also, with 22deg total at 4200rpm. US L48 auto (1112045) is 4deg initial with 18deg total at 4200. You can see the difference, and for 1973 L48 it got worse. GMH allocated 275hp to the HQ 350, GM gave the 1971 L48 manual 270hp at the same rpm. The extra 5hp is probably fair enough given the extra 4+deg advance and higher Octane fuel.

There is a "Holden 350", it is the stroked version of the Holden 5litre (same bore and stroke as a 350 but called 5.7L), but was never actually available in a real Holden, only in the HSV vehicles (HSV is a separate manufacturer that builds vehicles based on Holden product, bit like AMG and Mercedes).

Edited by user Wednesday, 10 May 2017 5:10:15 PM(UTC)  | Reason: Not specified

The late 1970 paperwork I have for XU7 says it was to be both CKD and SUP. There is a lot of SUP examples in the Service/Warranty records but I don't know if any records for Trentham (NZ), Trinidad, Malaysia and others exist. You'd imagine most were SUP.

HQ 350 Statesman came with only the single exhaust and a GTS Monaro front sway bar.

That could be a bit misleading. The HQ 350 engine was the same L48 option code, which was a particular level of engine option in the US. It doesn't adequately describe the physical engine differences, and doesn't really serve as a year on year basis for comparison.

The "actual L48 engine" was almost completely different between HT/HG350 Manual and HQ350.

A more accurate description would be something like:

HT/HG 350M: 1969 L48, 350cu in, 300Hp, 4 bolt mains, 4bbl carb, 10.25:1 compression.

HQ350 1970/71 L48, 350cu in, 270Hp, 2 mains, 4bbl carb, 8.5:1 compression.

The HQ350 engine is more like a HT/G 350 auto engine in configuration and performance, although virtually no physical components are shared.

The much vaunted late HG350 engine was just another plants way of producing an engine to the 1969 version of what L48 was supposed to be.

Edited by user Thursday, 11 May 2017 12:16:15 PM(UTC)  | Reason: Not specified

It could be misleading but is how it is. No different to the standard L31 308 used from HT through to mid VK. The engine changed significantly for HJ, changed even more again for HX, dropped compression during HZ (for VB), dropped compression again and changed significantly for VC (and WB) and again for VK.

In the same way the HQ's L30 engine (which was essentially the US L48 bar the dizzy) changed such that there is 4 x distinct versions (manual vs auto aside) aligning with US 1971-1974 L48 model years.

HQ 350 engine is not really any closer to a 1969-70 L48 as it is to a 1969 LM1 (the HT-HG auto engine). The difference between the HT-HG manual (L48) and the HT-HG auto (LM1) (dizzy aside) is the combustion chamber size. L48 uses fuelies (041 or 186 depending upon which engine plant built it), LM1 uses heads with the same valves, just with 75cc chambers. Not certain on port size on the LM1's 441 heads, might be slightly smaller than the 165cc on the L48's 041/186. Both 1969 LM1 and 1969-70 L48 engines share the identical bottom end. HQ L48 uses dished pistons and either 75 or 76cc heads (depending upon the model-year L48 it is based upon), plus some of them have smaller ports and pollution bumps in the exhaust ports. HQ also used the terrible Camaro type log manifold on one side from memory, whereas HT-HG used the far better Ramshorns on both sides.

The auto HT-HG is a faster accelerating car than the HQ, despite the HT-HG being heavier. Both cars share the same tune carby, same dizzy, same cam, just the 0.5:1+ lower compression ratio of the dished pistons and the different heads and an exhaust manifold.

According to US sources the LM1 was a deliberately under-rated engine slipped into Camaro for a few months in 1968 for stock class racing. The cars had a Muncie and 12 bolt, but GM only rated the engine at 255hp. A few months prior the 327/275hp engine in a Camaro got a Saginaw and 12-bolt. GM appear to have dropped the hp rating for the LM1 but left its torque alone at 365lbft@3200rpm. GMH gave the same engine 275hp@4800rpm but GM only 255hp. The US LM1 actually has the same 28deg max advance as the GMH HT-HG 350 auto, only difference is the US version has 2deg more initial and more vacuum (24deg rather than 15deg in the Holden).

Remember that GMH always specified the base 4BBL engine. The HK GTS327 used the US L73 250hp 327 which was the base 4BBL 327. The L48 was the base 4BBL 350 for 1967 through to 1970 (except for the 1968 months of the 1969 model year when the LM1 was available (gone and replaced by L65 2BBL by 1/69)). The L48 was also the base 4BBL 350 for HQ years other than at the end when LM1 was released again but only for California.

The late HG GTS350 engine is unique, only really existed in a Holden as far as we know. It was built like it is as 1971 L48 production had started by the time GMH needed them (1970 L48 engine production ceased late July 1970). The heads are Canadian cast, we think they are a spare part head for all prior 1.94/1.5 valve fuelies, which mean they have to cater for the 172cc 461X fuelies. Hence why the final HG GTS350 manual engines went a bit harder. The only reason GMH needed these engines was because "HT" ran longer than expected due to HQ being delayed and then GMH having to cut HT short and slot in HG. When the Tonawanda 350 manual engines ran out is supposed to be the end of HT and start of HQ (final quarter 1970).

Be careful of brochures. The original Engineering docs in the GM Heritage archives are better info. They list the 1972 Nova as:

307 130hp@4400rpm, 235lbft@2400rpm net, 8.5:1 (they have used 75cc heads here to drop compression, earlier 307 were 69cc chambers).
350 L65 is as you have typed
350 L48 210hp@4400rpm, 300ftlb@2800rpm net also 8.5

The L65 and L48 are the same engine bar the inlet and carby, other than the L48 has less total advance and less vacuum advance (L65 and 307 use the same dizzy).

307 and L65 use a single 2" system with single muffler and 2" tailpipes. L48 has a dual 2.25" system with single muffler and 2" tailpipes.

The 1971 L48 is actually a pivot engine as it is the only year that the engines were properly rated as both gross and net and for auto and manual. Here it is:

270hp@4800, 360ftlb@3200 gross
210hp@4400, 300ftlb@2800 net (manual)
175hp@4000, 290@2400ftlb net (auto)

These net figures at not "in-car", they are still done on an engine dyno but simulated as in a vehicle - this is a GM20 test IIRC.

1971 L48 is our HQ 350 manual engine, and the earlier auto 350 engine except again for carby, exhaust manifolds and distributer - our engines got far more advance for Super fuel.

1972 is net only and rated as manual only that I could ever find, only difference is 200hp rather than 210. This 1972 engine we really only got in auto HQ but I think some snuck into manuals (remember the US 1972 engine production started in 8/71).

1973 is net only and auto only, same rated power as 1971 auto figure but torque 260ftlb@2800. We only got this engine in auto 350 but again different carb and our dizzy hanged to the US L48 manual dizzy, so again more spark advance than the US vehicles.

1974 L48 actually increased in power, 185hp@4000 and 270ftlb@2600. We got this engine from 8/73 in auto HQ, except we got the 1972 L48 dizzy again and also got the 1972 L48 carby.


That 327 in the GMC is essentially the same engine in the HK GTS327 engine, minus the HD stuff like valve rotators etc.

1970 Camaro 2 barrel 9:1 is the 1969-70 L65 engine. It replaced the LM1 at the end of 12/68 in 1969 model year. The Camaro LM1 is our HT-HG GTS350 auto engine, other than the sump, carby, dizzy and exhaust manifolds (sump is obvious, we got a 1967 tune carby as from 1968 in the USA they had AIR across the board, our engine used the 327's dizzy for more advance as it ran on Super in Australia, and Camaro used log manifolds not ramshorns). The L65 in the USA is the same engine as the US LM1 other than the inlet and carby.

Correct, the HT GTS350 manual engine is the US 1969-1970 L48, again except for sump, carby, dizzy and exhaust manifolds.

The 1970 Z28 is 370hp in a Corvette, 360hp in a Camaro (exhaust manifolds account for the 10hp less). That is the weapon SBC, it is what Harry Firth wanted for Old Man Emu, his Bathurst HG GTS. A Phase3 would have trouble keeping up with one of those! It was canned due to cost as one factor, as it would have required an M22 Muncie and 12 bolt rear axle plus by the time it would have went into production the 1970 Z28 engine would be wrapping up (finished 7/70) and HG GTS350 itself wound up before the end of 1970 calendar year.

Edited by user Thursday, 7 December 2017 4:08:32 PM(UTC)  | Reason: Not specified

Pretty sure that is the ‘73. Does it have the 7041xxx carb and not a 1111500 dizzy?

It would have depended Nick on what 454 was used. The 400 that was to go in the HV/HJ was a 2BBL as were all 400’s until 1974, it was a low Hp, low comp, high torque engine. LF6 was its code. It was less suitable as a performance engine than a stock HJ 308, although in a heavy Caprice with air and steer the 400 was probably more at home. The LF6 was 255hp@4400 and 390lbft@2400 gross. The HJ 308 was 250hp@5000 and 320lbft@3400.

By the time the HQ arrived the 454 wasn’t much better than the LF6. If HQ was to get a 454 it would have been the LS5. In the USA, 1971 engine production ceased in July 1971. The 1971 LS5 was a goodie, 365hp and 550lbft. However 1972 LS5 dropped to 270hp and 468lbft, and with 1972 engine production from late July 1972 means this is what most HQ would have got. 1973 LS4 was 275hp, 468lbft. 1974 270hp, 458lbft. All great stump pullers but not really performance engines. Compared to the legendary 1970 (450hp) and 1971 (425hp, 575lbft) LS6 454 we all hear about, the 1972-4 LS5 would be slugs. I guess a comparison we can all relate to would be a stock XC 351 compared to a Phase II/III engine, or even a stock HQ 350 versus a HT-HG manual 350.