JR California style

Talk about anything and everything
IZU069
Power Moderator
Power Moderator
Posts: 962
Joined: Wed Sep 14, 2005 2:59 pm
Location: Melbourne (Orstralia)

Post by IZU069 »

As you said, an Australian-only harness would make things more expensive.
So why the change to a mechanical dizzy & ECGI?
Was it so that we could have more pollution than California?
(And I think Japan had tighter controls than USA & Ca anyhow. Certainly the new Tokyo diesel nano-particle standard is or was the toughest in the world. In fact Isuzu was the only diesel to comply.)

And how the heck refabricating a mechanical dizzy with its new timing can be cheaper than re-mapping an existing system beats me.


The knock control doesn't make sense. It is easier to retard timing digitally than to successively retard etc with analog circuits.
But the knock control on the ECGI/Jetronic Piazza does that irrespective of the mechanical dizzy's timing - it retards the dizzy's firing point (or rather, it adds less delay) and it would simply do the same to a mapped firing point.
And to add it to any mapping is easy - it's essentially just a few lines of code (if knock noise is there, retard x-degrees; if still there, retard again; if no knock start advancing (or after delay, reset to map) etc etc). But if not, do it as per my last paragraph.

The move back to a mechanical dizzy still makes no (technical or fiscal) sense to me.



The body manufacture method (or prod line) changed in 1985 or 1986. Although the bodies looked the same, the later body was a better construction.
At the time the Aussie order was placed, the body ordered was officially superseded.


So was it that GMH were slow to approve a much earlier proposal, and decided that programmed ignition was far too advanced for mere Australian mechanics or maybe too money-saving for customers?
Did GM influence GMH to further GM's politics with Isuzu (or GMH!)?

Hmmm...
IZU069 - ISUZU means a lot to me.
User avatar
Bugle
A total post whore
Posts: 953
Joined: Sun Jul 17, 2005 11:41 pm
Location: Sydney

Post by Bugle »

The G200W dizzy is different to a 4Z one, as far as I know the 4ZC1-T was the only EFI 4Z until the 4ZE1 came out?
So they would've developed the mechanical dizzy for the whole 4Z range, and maybe couldn't be bothered developing it for the 4ZC1-T until the prospect of $$ from the US market.

The knock control doesn't make sense from a technical perspective, but if ND had patented it and initially didn't allow Hitachi to run it on their ECU's then they'd have no choice but to go with ND's system if they wanted knock control.

What did they change on the body construction at that point apart from the rear panel?

I don't think we will ever know exactly why they did what they did unless an Isuzu engineer from the time signs up to the forum.
User avatar
wedgenut
Site Admin
Site Admin
Posts: 1520
Joined: Mon Jul 04, 2005 9:39 pm
Location: Hibiscus Coast NZ

Post by wedgenut »

Not exactly sure about the time line but as far as I know it was the 88 onwards models that had significant changes. The door interiors and trims were different, especially the door card and switch panels, large speaker boxes with built in tweeters etc. The rear quarter glass was different as was the "C" pillar. Bumper reinforcement was beefed up as well and then the more obvious changes like the rear lamp assemblies. The Bonnet lost its eyelids and became more rounded. In the US they introduced a hump to accomodate the higher plenum on the 4zd1 and the headlamps were twins but slimmer to complement the loss of eyelids.

If you really need to know more detailed FACTS as opposed to conjecture you need to consult 117coupe. He has some first hand Japanese cred gained directly from being over there and having good contact with Isuzu. As far as the Impulse is concerned all bets are off, in the early days they were LHD Jap models but later Isuzu America did more and more their own thing like fitting cockamamy electric automatic seat belts, crash pads on the dash and various other bling bling add ons we are used to not having.

Hashimoto and his mates looked the other way and probably shook their heads in disbelief. In Japan they kept on producing the JR series right through to 91 I believe.
So many cars, so little cash
IZU069
Power Moderator
Power Moderator
Posts: 962
Joined: Wed Sep 14, 2005 2:59 pm
Location: Melbourne (Orstralia)

Post by IZU069 »

Like I said, the changes were in the assembly and not cosmetic.

The guru I referred to is similarly qualified, but he has had more than several trips to Japan and Isuzu, he even owns the Australian rights to "Bellett" and a few other Isuzuan names. And it was thanks to him that Isuzu extended its 20-year sparts policy (which I believe was a standard Jap policy).


Not that I'm trying to one-up my knowledge or that particular guru. I just know how right that guru has been on so many occasions. Besides, 1988 is too late to have been the "new build" as relevant to the late 1985 order.


There was a way of identifying the difference - I vaguely recall folds on the front cabin kick panels, and spot welds... But nothing identifiable externally.
IZU069 - ISUZU means a lot to me.
Palos
Probationary
Probationary
Posts: 14
Joined: Wed Dec 03, 2008 6:27 am
Location: 805, CA

Post by Palos »

Bringing this back from the dead. That red impulse is sick!
User avatar
Piazza_man
Site Admin
Site Admin
Posts: 863
Joined: Sun Dec 12, 2010 9:53 pm

Post by Piazza_man »

I agree.
Post Reply