After I wrote that I went and did some reading and you at spot on:

XW GT engine is just a straight US spec 4V engine, 290hp, just under 11:1 compression, cast intake, small Autolite 4BBL etc.
XW GT-HO is the same engine with an alloy Buddy Bar intake, 600cfm Holley. What I read reckons a bigger cam though.

All up you'd expect that if the 290hp is accurate for the GT (which given its 1/4 mile times and 0-100mph times appears pretty right), and a well tuned GT-HO capable of mid to high 14s quarter @ around 92-94mph and 16.7/16.8s 0-100mph that the XW GT-HO was probably good for 310hp. This also shows that the properly tuned HT GTS350 that does around 16.3s 0-100mph and similar 1/4 mile times has around the same hp, essentially 300hp SAE gross as it is rated.

It is interesting that the PhaseII were the same basic 4V 2 bolt 11:1 300hp Cleveland as what was in the US and in GT's but with some performance changes: Solid cam and valve train mods, 780cfm Holley. These were not that much different in performance to the GT-HO with Windsor engine in 1/4 mile and 0-100mph despite the 3.5:1 rear axle so you'd probably say that in factory unmodified form they'd also be 310hp or thereabouts but at different revs and also peak torque at different revs.
The PhaseIII seems to have returned similar figures from the day, but all with 3.25:1 rear axle, shame none were properly tested with the 3.5 rear axle. Changes appear to be extractors, revised cam, slightly changed carby, Boss Mustang HD balancer, revised dizzy and rev limiter. Once source says they were also balanced, so maybe that explains the higher compression Terry - they were pulled apart and balanced so they must have had other pistons fitted if they were 11.5:1. The US Boss351 was 11.3:1. Given it was published in October 1971 that the best figures Ford ever achieved out of a modified PhaseIII was 232rwhp@7000rpm (with 1971 CobraJet intake and a few other tweaks which equates to maybe 330-345hp SAE gross), and that it performed similar 1/4 mile and 0-100mph as the PhaseII but using a 3.25 rear axle you'd have to think the standard PhaseIII had a few more horses, maybe 320-325hp SAE gross?

All interesting stuff. But not really Holden myths, so i'll let the thread get back to where it was.

Edited by user Thursday, 27 July 2017 3:55:23 PM(UTC)  | Reason: Not specified

The Green XAGTHO plated car was part of a pilot run prior to initial production and is in all ways a real GTHO. The other three cars were Red Pepper GTs taken from the line and delivered to the lot 6 Mahoneys Rd Ford workshop and were stripped down and then became hand built race prepared cars for the company's factory race program. They were upgraded to GTHO spec in the Lot 6 workshop. Some say they are not real GTHOs. But if Ford Motor Company takes three brand new GTs to their own workshop and then rebuilds them to a race prepared GTHO specification then they're pretty much GTHOs regardless of their initial production line build sheet says. So technically , there were Four XAGTHOs.

On another point, all XAGTs had 4V heads. Early XBs got 4vs too along with the toploader box. It is generally known that XBGTs went til March 1974 with the big heads but there are more than a few April cars with the big heads. Mine is April 74 and has 4Vs. There were probably a dozen or so more which went as far as July 1974.

Ford has never recognised reference to XWGTHOs being Phase One, Two or even 1 1/2. Al Turner was running the Australian Ford race operation and never used the term "Phase". Al Turner returned to the USA at the end of 1970. Howard Marsden was then appointed and immediately referred to the new XYGTHO as the Pasee Three. Not the Cleveland powered XWGHTO.

Edited by user Friday, 28 July 2017 10:24:33 PM(UTC)  | Reason: Not specified

XA GT automatic first got 4V heads but from mid 1972 they were 2V heads on them.

Nick, while I agree with most of that, I have 2 comments.

Firstly, I'm sure that the "race prepared" GT-HOs had all of the stuff that was required for homolgation, but I could bet last week's wages that they weren't "production perfect", in that the little things like the GT-HO badge on the centre console wasn't fitted etc. So IMHO weren't as "real" as the Calypso Green car.

AFAIK Howard Marsden first coined the term "Phase" with the Phase II. I'm sure we've had this conversation before, but I have a factory workshop manual titled "GT-HO Phase II".

Dr Terry

Edited by user Friday, 28 July 2017 10:29:33 PM(UTC)  | Reason: Not specified

Maybe.

If those 3 x XA GT's are GT-HO's then the 3 x LJ GTR's built as 6cyl GTR's and converted to 5.0L GTR's must also be considered "factory". GMH even registered at least two of them with the 308 engines. However they have always been and will always be originally assembled in the assembly plants as standard GTR's. Same with the SeaWitch van, it started life as a stock Opaline blue van. Plus many others.

If they were not a production car that could be bought by the public on demand they fail the credibility to be such a production car in their own right as such a car.

So there is no real point in claiming any such Phase 4, one exist and 3 others made up in fact do not make the grade as such a production car that was, like the P2 and P3 were truly a production model produced sold publicly new from the dealer floor to anyone.

The Holden Torana L34 does not cut the grade as such a car because it never was sold to the public as such.

We know they exist but so what, now if I could go back in a time machine and I still could not buy one in the day off the floor.

Who were they going to sell them too ? who wants a car without a arm rest.
They were only for people who wanted them for the race track work.
Be careful means, do not sell them but only to people in the know.

Ford had the XA RPO and only people in the know could get the good bits, the average dude had no idea at all and could not get one, just as it was with the L34.

Fact is that your average Joe Blow could not walk up and get the cars new from the dealer and that makes it not a public production car.


One of the cars that were a better than average car was the VU SS ute 50th anniversary if you were lucky you got the better performing engine than the others.

Anyone who bought a bench seat Holden Belmont in 1974 didn't get armrests or console shift either!

The L34 was built to homologate the LH Torana with good bits for Group C racing, there is no secrecy in that. It was the Evolution of type of the LH SL/R, of which from memory GMH had to build half. Exactly the same as the 4 x Group A Commodores were the evolution of type of the base vehicles. GMH didn't need to advertise the L34, it was intended for race teams (unlike the A9X). However anyone could buy one if they knew about it and tried hard enough. In fact you could argue it had to be a regular available vehicle to homologate it for Group C. The L34 was GMH's first Group C homologation too.

I had a look and cannot work it out. Could it be VC? And which spec/level?

Cheers
Nick.