Hi all those who like referring to heavy 6 cyl red rods as Starefire rods.

I have been doing some very basic research and have found that the following is how the rod development took place.

[73 Bathurst XU-1 rods batch 250?]
[1979 HZ Holdens, heavy rods]
[1979 Commodore heavy rods]
[Commodore reliability car XU-1 engine]
[1980 Starefire engines introduced]
[ VC Commodore engines with heavy rods

So as you can see the Starefire and Red Commodore engined rods were just a further development of the 73 Bathurst rods and nothing specific to either blue motor Holdens or Stare fire engines and in fact were old hat by then!

Read on for corrections.

Mike



Purpul Police

Edited by user Wednesday, 25 August 2010 11:47:42 AM(UTC)  | Reason: Not specified

Hi Mike

I noticed you mentioned the other day, that the intro date of the Starfire 4 was post VB, but this is not the case. The Starfire 4 was introduced in Sept 1978, post HZ but pre-VB.

AFAIK the development went like this:

1. First heavy conrods with big bolts - '73 Bathurst XU-1s.
2. First regular production usage - UC Starfire 4 .
3. Heavy rods supersede light rods for all 6-cyl engine mid-late 1979 (perhaps around Z prefix intro). I've seen too many HZ & VB 6-cyl engines with the regular rods to be convinced that the big rods were introduced to 6-cyl engines as early as 1977 or 1978.
4. All Blue & Black 6-cyl got heavy rods.

There are small differences between the XU-1 rods & the later rods but they are similar. I think the reason that people refer to them as Starfire rods is that these were the first ones used, that were commonly available.

Dr Terry


_________________________________________

When calculating a car restoration budget, be as accurate as you can & then double the final figure. It will be closer to the truth.

Thanks everyone for those corrections.

I actuallty went to the Commodore or Torana Starefire release in Perth, but I couldn't remember the year and a quick search in my books didn't quite show it, I will have some information somewhere I suppose.

I do know that the later rods were a little different to XU-1 rods, that is why I said that they were further developed rods.
The XU-1 rods were not perfect as they were weakened when the rod bolt head clearances were milled in, Holden fixed this by making them the same design as the V8 rod big ends.
There were several different sources for rods and the markings vary accordingly, it is unusual to find an original engine with the same marked rods.
There is also much variation in web thicknesses also when you really look at them.
Earliest HZ ZL engine with the heavy rods so far that I have seen is 31 E 9
Mike

Purpul Police